wallsand piers

Kansas Department of Transportation Design Manual

Abutments, Piers and WallsTable of Contents

3.11.1 General ................................................................................................................13.11.2 Abutments ...........................................................................................................13.11.3 Design ................................................................................................................143.11.4 Details ................................................................................................................153.11.5 Pier ....................................................................................................................25

3.11.5.1 General ..................................................................................................................253.11.5.2 Pile Bent Piers .......................................................................................................253.11.5.3 Column Bent Piers ................................................................................................273.11.5.4 Single Column/Cantilever Piers ............................................................................273.11.5.5 Pier Construction/Formwork .................................................................................273.11.5.6 Pier Beams .............................................................................................................273.11.5.7 Details ....................................................................................................................283.11.5.8 Columns ................................................................................................................453.11.5.9 Loads on Piers .......................................................................................................463.11.5.10 Application of Loads ...........................................................................................533.11.5.11 Pier Frame Analysis ............................................................................................53

3.11.6 Walls ..................................................................................................................543.11.6.1 MSE Design Considerations .................................................................................543.11.6.2 Earth Retaining Structures Review and Acceptance Procedures ..........................583.11.6.3 Purpose ..................................................................................................................583.11.6.4 General ..................................................................................................................583.11.6.5 Initial System Approval ........................................................................................583.11.6.6 Wall Selection Considerations ..............................................................................593.11.6.7 Economic Considerations for Wall Selection .......................................................593.11.6.8 Plan Preparation Requirements .............................................................................603.11.6.9 Requirements for Supplier Prepared Designs and Plans .......................................623.11.6.10 Materials Approval ..............................................................................................633.11.6.11 Consultants Responsibility ..................................................................................633.11.6.12 Department Responsibility ..................................................................................633.11.6.13 Sound/Noise Walls ..............................................................................................65

3.11.7 Wall Policy ........................................................................................................67

List of FiguresFigure 3.11.2-1 Typical Abutment Connection to the Approach Slab ...........................................5Figure 3.11.2-2 Abutment Aggregate Drainage System .................................................................6Figure 3.11.2-3 Abutment Strip Drain ............................................................................................7Figure 3.11.2-4 Integral Stub Type Abutment (Seismic Pile Connection) .....................................8Figure 3.11.2-5 MSE Retaining Walls (Semi-integral abutment < 5” of movement) ....................9Figure 3.11.2-6 MSE Retaining Walls (Semi-integral abutment < 5” of movement) ..................10

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Figure 3.11.2-7 MSE Retaining Walls (Semi-integral abutment < 5” of movement) ..................11Figure 3.11.2-8 MSE Retaining Walls (Semi-integral abutment < 5” of movement) ..................12Figure 3.11.2-9 Free Standing Abutment with Counterfort ..........................................................13Figure 3.11.4-1 Pintel Integral Abutment Beam Rest ...................................................................18Figure 3.11.4-2 Stub Type Abutments .........................................................................................19Figure 3.11.4-3 Comparison of “Stub” and “U-Type” Abutment ................................................20Figure 3.11.4-4 Preferred Wingwall Configuration ......................................................................21Figure 3.11.4-5 Curtain Wall ........................................................................................................22Figure 3.11.4-6 Counterfort Abutment With Curtain Wall and Battered Piles ............................23Figure 3.11.4-7 Semi-Integral with Shear Key Guides .................................................................24Figure 3.11.5.7-1 Pile Bent Pier ....................................................................................................31Figure 3.11.5.7-2 Pile Bent Pier Encased .....................................................................................32Figure 3.11.5.7-3 Monolithic Column Bent with Web Wall ........................................................33Figure 3.11.5.7-4 Web Wall Information .....................................................................................34Figure 3.11.5.7-5 Free Standing Column Bent .............................................................................35Figure 3.11.5.7-6 Frame Bent .......................................................................................................36Figure 3.11.5.7-7 Rigid Frame Bent “Grass Hopper” ..................................................................37Figure 3.11.5.7-8 Solid Pier .........................................................................................................38Figure 3.11.5.7-9 Pile Bent with Web Wall “Hinged” .................................................................39Figure 3.11.5.7-10 Single Column Bent .....................................................................................40Figure 3.11.5.7-11 Single Column Bent ......................................................................................41Figure 3.11.5.7-12 Pile Bent with Web Wall ...............................................................................42Figure 3.11.5.7-13 Railroad Crash Wall (A) ................................................................................ 43Figure 3.11.5.7-14 Railroad Crash Wall (B) .................................................................................44Figure 3.11.5.9-1 ...........................................................................................................................49Figure 3.11.6.1-1 MSE Retaining Walls (integral abutment < 2” of movement) .........................57

AppendixAppendix A Structure Protection Guidelines .................................................................................1Appendix B Example Calculations .................................................................................................1Appendix C Sheet Pile Retaining Wall Example MathCadd ..........................................................1Appendix D Noise Abatement Policy .............................................................................................1Appendix E Landscape Retaining Wall Policy Revision ...............................................................1



Disclaimer:�Disclaimer:��This�document�is�provided�for�use�by�persons�outside�of�the�Kansas�Department�of�Transportation�as�information�only.�The�Kansas�Department�of�Transportation,�the�State�of�Kansas,�its�officers�or�employees,�by�making�this�document�available�for�use�by�persons�outside�of�KDOT,�do�not�undertake�any�duties�or�responsibilities�of�any�such�person�or�entity�who�chooses�to�use�this�document.�This�document�should�not�be�substituted�for�the�exercise�of�a�person�s�own�UProfessional�Engineering�JudgementU.�It�is�the�user�s�obligation�to�make�sure�that�he/she�uses�the�appropriate�practices.�Any�person�using�this�document�agrees�that�KDOT�will�not�be�liable�for�any�commercial�loss;�inconvenience;�loss�of�use,�time,�data,�goodwill,�revenues,�profits,�or�saving;�or�any�other�special,�incidental,�indirect,�or�consequential�damages�in�any�way�related�to�or�arising�from�use�of�this�document.�

Typographic�Conventions:�

The�typographical�convention�for�this�manual�is�as�follows:�

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Non�italic�references�refer�to�locations�within�the�KDOT�Bridge�Design�Manuals�(either�the�LRFD�or�LFD),�or�Hyper�links�shown�in�red,�as�examples:�

� Section�3.2.9.12�Transportation�� Table�3.9.2�1�Deck�Protection�

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Italic�references�and�text�refer�to�locations�within�the�AASHTO�LRFD�Design�Manual,�for�example:�

� Article�5.7.3.4�

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Italic�references�with�a�LFD�label�and�text�refer�to�locations�within�the�AASHTO�LFD�Standard�Specifications,�for�example:�

� LFD�Article�3.5.1�



3.11 Abutments, Piers and Walls

3.11.1 General This section contains guidance for the design and detailing of abutments, piers and retaining walls. This section also contains information about sheet pile walls, structure protection and noise walls in the appendix. Abutments and piers are used to support bridge superstructures, whereas walls primarily function as earth retaining structures. In most cases abutments and piers, are reinforced concrete elements. Walls can be constructed of various materials or combinations of materials.

The preferred details for connecting the superstructure to the substructure are dependent on the geometry and type of bridge. For example, flexible substructure units supported by a single line of piles may be constructed integral with the superstructure. Conversely, short stiff substructure units or long superstructures are detailed with expansion bearings between the superstructure and substructure to reduce the design loads transmitted to the substructure units. For intermediate con-ditions where joint elimination is desired, a semi-integral abutment may be used. Expansion joints are necessary and required on approach slab pavement just outside the limits of the bridge, however jointless bridge deck construction, where feasible, is preferred by KDOT to eliminated maintenance concerns.

3.11.2 Abutments

Types and Usage:Abutments are used at the ends of bridges to retain the embankment and carry the vertical and horizontal loads from the superstructure into the substructure.

Abutments fall into two general categories: the spill-through abutment and the retaining-wall (vault) type abutment. A bridge with a spill-through abutment may require additional length to cover the embankment slopes. However, spill-through abutments are considerably more econom-ical, the comparative cost between a longer bridge with a spill-through abutment versus a shorter bridge with a large wall-type abutment could be about the same. Spill-through type abutments have proven to be relatively maintenance free elements and are preferred.

Abutments may be further categorized as either free-standing, with an expansion joint in the deck slab, integral or semi-integral, with an expansion joint only in the approach slab. To eliminate joints and reduce initial cost as well as ongoing maintenance costs, KDOT prefers abutments to be integral or semi-integral with the superstructure wherever practical. In general, it is KDOT pol-icy to use integral abutments on steel bridges up to 300 ft. in length and on prestressed bridges and concrete haunched slabs up to 500 ft.. Semi-integral type abutments can be used up to the limits of the expansion joints on the approach slabs.

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Within the categories mentioned above the type of abutment to use for a particular structure is normally governed by economics. Other factors that may be involved in selecting an abutment type are the required channel area and section, minimum horizontal clearances, environmental, length of bridge, type of geology, safety and aesthetics.

The basic types of abutments are:

• Stub Type Cap on piling, drilled shafts or keyed into rock

• U Type on piles or drilled shafts

• Column Bent with or without web wall utilizing a pile cap or drilled shafts

• Pile Bent with a web wall

If the length, along the centerline of the abutment, is greater than 90 ft., a 1 in. expansion relief joint should be located between bearings near mid-length. On stage constructed abutments, a total length of 120 ft. or less may be permitted without requiring a 1 in. expansion joint. For abutments located on superelevation or transition elevation, the base of an abutment shall be constructed level using reinforced pedestal bearing seats, if the difference between the low and high elevation of the bridge seat is 10 in. or less. For a difference in elevation less than 20 in., the base of the abutment cap shall be stepped with the reinforcement continuous through the transitions. For dif-ferences greater than 20 in., the base should be sloped to match the roadway cross-slope.

Provide a separation/ isolation from the thermal movements of the abutment and any adjacent wall elements. Flexible elements (MSE Walls) and inflexible elements (Bridge Abutments) must be allowed to move independently- KDOT has experienced instances when this idea was not fol-lowed, the results are repairs and/or constant maintenance issues. The designer will consider both longitudinal and transverse movements of the abutment and wall system.

Abutments under expansion joints (free-standing) shall have a multiple layers of protection against the potential for leaking expansion joints sometime in the future. Use epoxy coated rein-forcement in the abutment backwall and abutment beam. Slope the beam seat to drain and use bearing risers to keep debris and water from ponding. All exposed surfaces of backwalls, bridge seats, and front faces of pile caps will be coated with Substructure Waterproofing Membrane. For cases involving both existing and new concrete, such as structure widening, apply this protection to both new and old concrete.

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Pile Orientation:

• For integral abutments maintain a weak axis pile orientation that is perpendicular to the cen-terline of the bridge for bridge skew angles of 30 degrees or less.

• For integral abutments with bridge skew angles greater than 30 degrees, maintain a weak axis pile orientation that is parallel to the center line of the abutment.

• For free-standing and semi-integral abutments, the strong axis of the pile will be placed paral-lel to the center line of the abutment.

Free-standing or semi-integral abutments can have up to half of the piles in any row battered and oriented to resist horizontal earth pressures. Pile batter should be less than 3 to 12, horizontal to vertical. The designer should check the placement of battered piles at the bottom of the abutment beam so the edge clearance is not reduced below requirements.

Stub Type Cap abutments are the most commonly used type. They may be integral, semi-integral or free-standing. Normally, only steel H-piles are allowed to be used in integral abutments because of flexibility. Steel piles in integral abutments shall be placed with the weak axis according to the pile orientation mentioned above.

U-Type abutments have wing walls which are parallel to the roadway, the wing walls should be supported on piling or spread footings. This abutment type is used when grading around the bridge is restricted and/or there are other geometric restrictions.

Column Bent abutments are used rarely and only where geology requires a spread footing or when other special conditions exist.

Pile Bent abutments with a web wall are becoming more common on single span bridges. When used with slab bridges that are designed and constructed to be integral, the moment resisting wall can increase the efficiency of the structure.

Free-standing (expansion) abutments shall have a minimum backwall thickness of 1ft.. Free-standing abutments approximately 50 ft. and greater in length (measured along centerline abutment) shall have a concrete lug or counterfort and pile at the mid-point of the abutment for stability purposes. To resist lateral loads all free-standing abutments have some battered piles in the row of piles closest to the bridge. Do not batter all the piles in a single row of piling, this can cause significant bending stresses if the fill material settles.

Drainage:Drainage often collects behind backwalls due to opening of the joint between the approach slab and the slab rest or when the joint at the end of the approach slab leaks. Current practice is to specify an abutment aggregate drainage system for structures with integral and semi-integral abutments. The use of a traditional strip drain for Standard Haunched Slabs (RCSH) and other abutment types is recommended.



Approach Slab:All structures will be designed with an approach slab rest parallel to the abutment backwall. Detail the approach slab to be attached to the abutment with reinforcement of suitable capacity and spacing. See Figure 3.11.2-1 Typical Abutment Connection to the Approach Slab for details. Allow the approach slab to “float” between the wings for U-Type abutment without a slab rest or attachment to the wings. Approach Slab details can be found through KDOT Authentication and Resource Tracking (KART) found at http://kart.ksdot.org/ and are labeled RD711 to RD715. For joint openings greater than 4 in. a special design will be required. See Section 3.14 for details.


http://kart.ksdot.org/


Figure 3.11.2-1 Typical Abutment Connection to the Approach Slab



Figure 3.11.2-2 Abutment Aggregate Drainage System



Figure 3.11.2-3 Abutment Strip Drain



Figure 3.11.2-4 Integral Stub Type Abutment (Seismic Pile Connection)



Figure 3.11.2-5 MSE Retaining Walls (Semi-integral abutment < 5” of movement)



Figure 3.11.2-9 Free Standing Abutment with Counterfort



3.11.3 DesignNormal wings used on a stub type abutment (wings 90º to centerline roadway or that follow the skew) are required on all bridges with integral abutments. Both semi-integral and free standing abutments may be used with u-type or stub abutments, with the later being preferred.

Earth Pressures:Abutments are typically supported on piles, drilled shafts, or spread footings in rock. Abutments designed with a strip drain drainage system cannot provide the movement required to achieve “active” soil pressure conditions. Therefore, the design backfill pressure for abutments should be based on “at-rest” conditions. Abutments designed using an abutment aggregate drainage system with geofoam wil provide enough movement to achieve “active” soil pressure conditions. If geofoam is provide abutment wing walls will behave similarly to abutment backwalls, the designer can assume “active” conditions, if not use “at-rest” conditions.

Active conditions are not appropriate for backfills containing cohesive materials. The remolding properties of cohesive soil specifically, a clay backfill will exert “at-rest” pressures, the structure will yield resulting in the earth pressure exerted by the clay reducing to “active” conditions, the reconsolidation process will occur and earth pressures will increase to the “at-rest” condition and the process with start over. It should be noted the use of a sand backfill is not recommended in any condition due to its proclivity to not be free-draining because it accumulates fines and its tendency to only achieve a densely compacted state under repeated dynamic loading, i.e., in service under traffic loading.

The design pressures should include residual stresses caused by compactive efforts or stresses from swelling pressures or excess hydrostatic pressures. Hydrostatic pressures should be included used when the backfill material is not free-draining.

Live Load Surcharge:Live load surcharges are minimized for abutment backwalls because of the inclusion of the approach slab rest for straight type abutments, but because the approach slab “floats” between the wings it should be included in wing walls which are parallel to the roadway.

Thermal Pressures and Force Effects:Due to the length limitation imposed on integral abutment type bridges, abutment pile stresses are normally not considered. KDOT has not observed excessive distress in the piling. However some distress in the concrete has been observed in the wings of straight type abutments outside the influence of the girders thrust; include additional shear reinforcement in these regions or extend the geofoam over the abutment wings to eliminate this force effect. The abutment piles can assumed to be fixed at about 15 ft. below the bottom of the abutment beam for piles driven into sand and 10 ft. for piles driven into clay. Use these values when building the abutment substructure models to determine the force effects from temperature changes. For abutments on drilled shafts the point of fixity can be determined from using the program SHAFT 6.0.



Live Loads:Loads, including concentrated loads, which are transmitted to an integral or semi-integral abutment from the superstructure, can be assumed to be a uniform load distributed over the entire length of the abutment beam.

Design piling for axial loads only. Assume that one half of the approach slab load is carried by the abutment. Distribute the factored live load over the entire length of abutment. Apply the number of lanes that will fit on the superstructure adjusted by the multiple presence factor, do not include impact.

Research indicates that the longitudinal moment at the abutment/slab connection is approximately equal to 33% of the computed fixed-end moment. Design the longitudinal deck reinforcement at the abutment for 50% of the fixed end moment due to live load only.

3.11.4 Details

It is KDOT’s preference not to pass utilities through the abutment backwall, but where conduit extends through an abutment, provide horizontal dimensions from a working point to the location where the conduit penetrates the front face of the abutment or the outside face of the wingwall. The elevation at mid-height of the conduit should also be provided. Contact KDOT Bridge Man-agement whenever a utility is placed in a bridge substructure.

Use preformed anchor bolt holes for bearing devices to prevent drilling or cutting into the rein-forcement.

For presentation clarity, detail abutments with complicated layouts on separate sheets. Identical abutments (except for minor elevation differences) may be detailed on common sheets.

For semi-integral abutments provide shear keys to guide the bridge movement and to restrain the bridge laterally. The keys will be shaped to prevent the bridge from binding. Do not rely on the bridge wings wall as the sole means of lateral support. See Figure 3.11.4-7 Semi-Integral with Shear Key Guides for an example.

All reinforcement, except those completely in the footing, shall be epoxy coated. The minimum size of longitudinal reinforcement in abutment and wingwall footings is No. 6 bars.

Provide shrinkage and temperature reinforcement per Article 5.2.6. For sections over 48 in. thick provide a minimum of No. 5 bars at 1 ft.. Temporary construction loads may require additional reinforcement.

For bearing pedestals over 2 in. tall provide both directions under the bearings. For pedestals with a height of 2 in., only the transverse reinforcement is required. Horizontal steel in pedestals should have 2 in. of clear cover to bridge seat. Provide a minimum of 2 in. of clear distance



between anchor rods and reinforcing tie bars.See Section 3.9.8 for negative moment reinforcing steel requirements when using integral abutments on deck-girder superstructures.

Use a minium thickness of 3 ft. for the abutment wall for steel bridges and 2’-6” for prestressed bridges.

Locate the bottom of the abutment beam as shown below.



For all steel bridge integral abutments use the abutment beam rest shown in Figure 3.11.4-1 Pintel Integral Abutment Beam Rest. If the structure is on a inclined grade greater than 2.0% then pintel the beam rest and detail slotted holes in the bottom of the steel beams that capture the pintel bolt and stabilize the beam from movements. This is described in Section 3.6.4.6 Integral Abutment Beam Supports.

Limit the length of the wing wall cantilever to 8 ft.. Use piling to support longer the wings. For detailing purposes provide a horizontal construction joint at the elevation of the concrete pile cap because usually the upper portion of the wingwall is cast with the diaphragm and deck.

For free-standing abutments if the backwall is greater than 6 ft. tall or if the abutment is 40 foot or greater in length then counterfort the backwall. Counterfort abutments will have at least one ver-tical pile or shaft for support.

For seismic requirements detail the connection between the piling and the abutment beam using spiral reinforcement as shown in Figure 3.11.4-1 Pintel Integral Abutment Beam Rest. Tie the piles to the abutment beam by detailing shear stud anchors or drilled holes with reinforcement to provide a positive connection.

For free standing abutments, include pedestals (bearing risers) under bearings and slope the bridge seat between pedestals to provide drainage away from the parapet wall and bearings. A standard seat slope provides one inch of fall from the back of the seat to the front of the seat. In no case should the slope be less than 2 percent. Protect the bridge side of the back wall and the bearing seat with a epoxy substructure waterproofing membrane.

Limit the maximum pedestal height to about 9 in.. The minimum pedestal height is 2 in. (at the front of the pedestal). Set back pedestals a minimum of 1½ in. from the front face of the abut-ment.

Curtain Walls:Curtain walls extend perpendicular to the bridge side of the back wall to prevent soil from coming in contact with the bearing devices on free standing abutments. If they are needed, curtain walls should be considered as a viable means of protecting the bearings, bearing seats and shortening the length of the wing walls. This is most appropriate for deeper girder bridges where the wings can become excessively long or where the geometry would prevent proper grading of the berm slopes. See Figure 3.11.4-5 Curtain Wall for details.



Figure 3.11.4-1 Pintel Integral Abutment Beam Rest



Figure 3.11.4-2 Stub Type Abutments



Figure 3.11.4-3 Comparison of “Stub” and “U-Type” Abutment



Figure 3.11.4-4 Preferred Wingwall Configuration



Figure 3.11.4-5 Curtain Wall



Figure 3.11.4-6 Counterfort Abutment With Curtain Wall and Battered Piles



Figure 3.11.4-7 Semi-Integral with Shear Key Guides



3.11.5 Pier

3.11.5.1 General A wide variety of pier types are used in bridge construction. The simplest may be pile bent piers where a reinforced concrete cap is placed on piling. A more typical pier type is a cap and column pier with columns supported on individual footings supporting a common cap. It is typical for cap and column type piers with standard roadway widths have from three to five columns. Do not use two columns to support a pier beam. The spacing of columns depends on the superstructure type, the superstructure beam spacing, and the size of the columns. At times wall piers may be used to support superstructures. Where extremely tall piers are required, columns may have a strut con-nection and between the columns near the lower one third of the columns to create frame action and bracing. It is preferred for stream crossings not to place a pier in the main part of the channel, but rather to span the channel with piers on the lower over-bank adjacent to the main channel.

Piers under deck joints (at unit breaks) shall have a multiple layers of protection against the poten-tial for leaking expansion joints sometime in the future. Use epoxy coated reinforcement in the pier cap. Slope the top of the beam to drain and use bearing risers to keep debris and water from ponding. All exposed surfaces of the top of the pier beam will be coated with “Substructure Waterproofing Membrane”. Coat the sides of the pier beam for a distance of 12 in. from the top to promote a vertical flow. For cases involving both existing and new concrete, such as structure widening, apply to both new and old concrete.

Protect columns in areas near vehicular splash zones. Columns located near the traveled way or in urban areas where “tunnel like” effects are created by wider multilane overpasses the constant spray or mist contacting the column surfaces create the potential for corrosion. For columns in splash or spray zones use a minimum of 3 in. of cover and epoxy coated reinforcement for the lon-gitudinal and spiral reinforcement.

3.11.5.2 Pile Bent PiersPile bent piers consist of a row of piles “soldier pile” usually consisting of five or more driven to bearing and encased by a concrete web wall. The piles should extend into the pier cap to provide continuity. It is not recommended to stop the piles within the web wall and continuing on as a structural reinforced wall. Embed the web wall a minimum of 2 ft. below the lowest point in the stream bed for stream crossings bridges. If there is evidence of stream migrations or sandy condi-tions exist, embed the web wall 6 ft. below the stream bed. These requirements are not intended to protect from scour, but rather to protect the piling from wet and dry cycles.

Pile bents are economical and may be used to support various types of superstructures. They are normally used on low-level, short-span bridges. Pile bents are generally not used for overpasses due to the severe damage they may receive from vehicle impact. Open pile bents are to be used cautiously on stream crossings where debris might be a problem; they may be encased in a concrete wall to reduce the possibility of debris snagging on the substructure. A concrete wall also produces smoother flow and thus reduces streambed erosion.



Pile bents may be constructed of prestressed concrete pile or steel H-piles. Piles for pile bents shall penetrate not less than 1/3 the unsupported length of the pile (unless refusal is encountered) nor less than 10’-0” into hard cohesive or dense granular material. For pile bent piers the “unsupported length” shall be defined as the portion of the pile from ground line ( or scour line) to the bottom of the pier cap or wall.

Piling exposed to a corrosive environment should be protected .

In the structural analysis of pile bents, a determination needs to be made as to the depth below the ground surface at which the piles may be considered fixed. Refer to Vol. I, Chapter 10 of the USS Highway Structures Design Handbook for a method to estimate the depth of fixity. See Vol. II, Chapter 11 in the above reference for a design example. Another method to estimate the depth of pile fixity was presented in the December 1976 issue of the ASCE Civil Engineering Magazine “The Equivalent Length of a Pile or Cassion in Soil” by Peter Kocsis.

The reinforced concrete caps for pile bents shall have a minimum width of 2’-6”. For the design of pile bent piers which are based on the assumption of a rigid connection (100% fixity) between the piling and pier beam, a minimum pile embedment of 1½ D is recommended (D = nominal diameter). Punching shear in the pier beam shall be checked at the pile location.

The pile embedment of 1½ D is the result of research done by the U.S. Army Corps of Engineers**. Note, the referenced report was conducted using computer modeling and not physical testing. The report assumed a side cover of 1D and analyzed pile spacings up to 5D. The report noted a 1ft. embedment produced a fixity ranging from 61 to 83%. The conclusion of the report indicated an embedment of 2D would provide full fixity. A minimum of 1½ D is recommended at this time. Provide a side cover minimum of 6 in. to approximate the behavior of the test model.

** “Fixity of Members Embedded in Concrete”, Technical Report M-339, Feb. 1984, U.S. Army Corps of Engineers Research Laboratory.

A pile encasement wall shall provide a concrete cover of at least 6 in. to the pile with an overall minimum thickness of 2 ft.. KDOT specifications allow a variation of 2 in. in the head of the pile after driving. This should be considered in setting wall width. The encasement wall is not considered structural, however, a nominal amount of reinforcing steel should be provided so the wall stays in place. The recommended minimum reinforcement is #4 bars horizontal and vertical at 1’-6” centers with #3 cross ties at 4’-6” center to center both vertical and horizontal. The cross ties should have a 180 hook on one end and a 90 hook on the other end. See Figure 3.11.5.7-12 Pile Bent with Web Wall



3.11.5.3 Column Bent PiersColumn bents are most commonly used for overpass structures and where wide piers are required due to large skews or wide roadways. Column bents are generally used in lieu of pile bents when spread and pile footings or drilled shafts are recommended for the foundation.

Column bent piers supporting bridges over railroads and located within 25 ft. of the centerline of the railroad track requires a crash wall. See “Protection of Structures” Figure 3.3.4.7-1, for crash wall criteria.

Column bent piers located in streams subject to ice, fast currents or debris accumulation should be constructed with a web wall between columns. On slab bridges, the top of web wall shall stop approximately 1ft. below the bottom of the pier beam. The minimum thickness on a web wall should be 1ft.. Web walls can be structural or non-structural. Structural walls are generally found on girder bridges where beam reactions are transmitted to the pier beam between columns. Joints between the face of the column and the web wall are not allowed on structural web walls. Reinforcing steel in the bottom of structural web walls is usually sized for the simple beam moment. Walls are usually deep enough so a nominal amount (temperature and shrinkage) of reinforcing is sufficient. A minimum of 2-#6 bars should be placed at the bottom of all walls to prevent cracking.

3.11.5.4 Single Column/Cantilever PiersSingle column piers are used for all types of crossings. They are generally more economical when used in high level bridges or in large river crossings. On skewed crossings, the single column pier allows the bridge to be constructed square. This provides for easier construction and thus a more economical bridge.

To accommodate wider roadways with a single column, the “hammer head” pier can be used to advantage. If a stream or reservoir location is subject to ice loads, the mass of a single column pier and footing aids in resisting the lateral loads.

For piers with large cantilevers, consideration should be given to concrete creep cracking over the long term.

3.11.5.5 Pier Construction/Formwork(See KDOT Specification, Section 701, “Concrete Structure Construction” for curing times required for footings, columns and pier beams.)

3.11.5.6 Pier BeamsAnalyze the pier beam on multiple column bents as a continuous beam. The column spacing should be adjusted to balance the exterior overhang moment with the other moments in the beam. Ignore the effect of debris web walls in contact with the bottom of the beam when designing the pier beam.


http://www.ksdot.org/burDesign/bridge/lrfd/LRFD_3_3_Loads.pdf


Pier beams should normally be 6 in. wider than the column (3 in. overhang on each side of the column).

For bridges where the skew angle does not exceed one degree, the designer should consider a right angle bridge with skewed columns. To keep equal span lengths, the pier cap is constructed square and widened to accommodate the skewed columns. Where bearing pads or plates are used, the beam edge clearance should not be less than 6 in.. For skews greater than one degree but less then five degrees, with approval, this type of layout may be considered but the pier cap should not exceed the column dimension by more than 18 in.. The eccentricity of the column load must be considered as well as the economy of the extra material used. Where horizontal clearance is a factor, the designer must also check the clearance to the pier cap to see if it falls below the required vertical clearance.

Pier beams on free standing piers with bridge seats exposed to deck or joint drainage should have epoxy coated steel. The top surface should be coated with a waterproofing material such as “Substructure Waterproofing Membrane”.Preferably, elastomeric pads should be placed on a raised concrete step. The reinforced step shall be a minimum of 3ft. and a maximum of 8 ft. high.

3.11.5.7 Details

To facilitate the use of standard forms, detail round and rectangular pier columns and pier caps with outside dimensions that are multiples of 2 in..

In general, the column should be reinforced to between 1% and 2% reinforcing steel. Size the column to accommodate these percentages.

When laying out piers, consider the economy to be gained from reusing forms (both standard and non-standard) on different piers constructed as part of a single contract.

Dimension piles, footing dimensions, and center of columns to working points.

For pier caps (with cantilevers) supported on multiple columns, space the columns to balance the dead load moments in the cap.

Label the ends of piers (South end, North end, etc.). Add a separate sheet with only substructure layout information for bridges with complex geometrics.

The minimum column diameter or side of rectangular column is 2'-6"

Slope pier caps in a straight line and utilize concrete pedestal beam seats when possible. Pedes-tals shall be set back at least 1½ in. from the edge of cap and be no taller than 9 in.. Consider omitting pedestals if their height is less than 1 in..



Choose a pier cap width and length that is sufficient to support bearings and provide adequate edge distances. As a guide, choose a pier cap depth equal to 1.4 to 1.5 times the width.

The bottom of the pier cap should be approximately parallel to the top. Taper cantilever ends about 1/3 of the depth of the cap. When round pier columns are required, use rounded pier cap ends as well. The ends of pier caps for other types of pier columns should be flat. Detail solid shaft (wall) piers with rounded ends for both the cap and shaft.

Integral Steel Box Beam Pier Caps:Avoid the use of steel box beam pier caps whenever possible. Conventional concrete pier caps or prestressed / post-tensioned caps are preferred.

To ensure that components are constructible, review the design details of box beam pier caps with the fabrication inspector early in the plan development process. Plan to create a Project Special Provision that requires full shop assembly and a procedure created from the full assembly. As a minimum require 25% pinned and 50% fully tightened bolts for the assembly.

The minimum dimensions of a box pier cap are 3ft. wide by 4'-6" high. Make access openings within the box as large as possible and located to facilitate use by inspection personnel. The min-imum size of access openings in a box pier cap is 18" x 30" (with radius corners.).

Provide access doors near each end. If possible, locate the door for ladder access off of the road-way. Orient the hinge for the access doors such that doors swing away from traffic. Access doors can be placed on the side of box pier caps if they are protected from superstructure runoff. If not, locate in the bottom of the cap.

Bolted internal connections are preferred to welded connections. Fillet welds are preferred to full penetration welds.

Avoid details that may be difficult to fabricate due to clearance problems. Assume that welders need an access angle of at least 45 degrees and require 18 in. of clear working distance to weld a joint. The AISC Manual of Steel Construction contains tables with entering and tightening clear-ance dimensions for bolted connections.

Paint the interior of boxes white for inspection visibility and for corrosion protection. Provide drainage holes with rodent screens at the low points of the box.

Piers Adjacent to Railways:Piers located within 50 ft. of the centerline of railroad tracks are not required to have crash walls incorporated into their design. Article 3.6.5.1 eliminated that requirement.Piers located within 25 ft. of the centerline of railroad tracks must have crash walls.

Crash walls must meet the following geometric requirements: (AREMA 2.1.5.1 and C-2.1.5.1)



• Top of crash wall shall extend a minimum of 6 ft. above top of railroad track when pier is between 12 ft. and 25 ft. from centerline of tracks and 12 ft. above top of railroad track when pier is 12 ft. or less from centerline of tracks.

• Bottom of crash wall shall extend a minimum of 4 ft. below ground line and 6 ft. below the base of the rail.

• Crash wall shall extend one foot beyond outermost columns and be supported on footing.• Face of crash wall shall be located a minimum of 6 in. outside the face of pier column or

wall on railroad side of pier.• Minimum width of crash wall is 2.5 ft..• Minimum length of crash wall is 12 ft..

See Figure 3.3.4.7-1 Railroad Grade Separation Crash Wall Details for a graphic of the above cri-teria.




Figure 3.11.5.7-1 Pile Bent Pier



Figure 3.11.5.7-2 Pile Bent Pier Encased



Figure 3.11.5.7-3 Monolithic Column Bent with Web Wall



Figure 3.11.5.7-4 Web Wall Information



Figure 3.11.5.7-5 Free Standing Column Bent



Figure 3.11.5.7-6 Frame Bent



Figure 3.11.5.7-7 Rigid Frame Bent “Grass Hopper”



Figure 3.11.5.7-8 Solid Pier



Figure 3.11.5.7-9 Pile Bent with Web Wall “Hinged”



Figure 3.11.5.7-10 Single Column Bent



Figure 3.11.5.7-11 Single Column Bent



Figure 3.11.5.7-12 Pile Bent with Web Wall



Figure 3.11.5.7-13 Railroad Crash Wall (A)



Figure 3.11.5.7-14 Railroad Crash Wall (B)



3.11.5.8 ColumnsColumns may be circular (preferred), rectangular, or variable in section. The minimum recommended diameter for a round column is 2’-6”. Larger diameters should be in 6 in. increments. The recommended minimum size of a square column is 2 ft.. Size the columns to be 6 in. smaller than the outside shaft for the construction purposes.

Columns shall be designed as tied columns. For compression controlled = 0.80 allowing for a variation from the column value to the flexural value of = 0.90 for tension controlled, pure bending as the axial load strength decreases from 0.8[0.85 f’c (Ag-Ast+fy*Ast)] or Po, whichever is smaller, to pure bending with no axial load.

KDOT, in partnership with KSU’s Civil Engineering Department, has produced useful software for the design and analysis of reinforced concrete columns for bridge structures. This software is available for download and use through KDOT Authentication and Resource Tracking (KART) found at http://kart.ksdot.org/. The software has the ability to analyze the design, unconfined and fully confined sections of a column. For new construction the designer should limit the load points (moment and axial) to fall within the design interaction curve.

See Article 5.7.4.2 for reinforcement requirements of compression members. The minimum reinforcement shall be 1% of the gross area of the column or per Equation 5.7.4.2-3 which ever is larger. The KDOT preferred lateral reinforcement in round columns is the spiral tie with a 6" pitch. Currently, the maximum diameter of spiral reinforcing is 72 in.. For square, rectangular or large diameter columns (> 6 ft.) use individual lateral ties with a maximum spacing of 1 ft.. A closer spacing should be used near the junction of the column with the beam or footing.

Reinforcing dowels projecting from a spread footing are normally provided extra long. This is to provide adequate splice length in the event the footing has to be lowered slightly in the field due to adverse foundation conditions.

Columns on bridges which come in contact with salt water drainage or spray are required to have some form of protection. Protection may be in the form of extra concrete cover over the reinforcing steel, use of a concrete sealer or, in some cases, epoxy coated bars may be used.

See Section 3.3.4.4 for a brief explanations of modulus of elasticity to be used in the computation of thermal stresses in the columns, a value of one-third of that used in dynamic loads can be used.

Columns for structures located in KDOT Seismic Zone IB or IC will have additional reinforcement located at the top and bottom of the column extending into the pier beam or footing to form plastic hinge zones per Figure 3.3.4.8-1

See Appendix B Example Calculations: for a method to compute stresses in columns due to change in deck length and the distribution of forces to each pier.


http://kart.ksdot.org/




3.11.5.9 Loads on Piers

The following loads shall be considered in the design of bridge piers. Reference is made to Section 3.3.1, Application of Loads in the LRFD Bridge Design Manual.

(a) Live Load

The live load is the HL-93 truck or tandem loading which must be checked for the H.E.T. load rating and may control. The lane loadings are assumed to occupy a width of 10 ft. and are placed anywhere within the 12 ft. design traffic lane as to produce the maximum stresses in the pier. When a pier is loaded with three or more design traffic lanes the live load is reduced by a multiple presence factor. When there is only one design traffic lane the factor is 1.20. See Table 3.6.1.1.2-1for the multiple presence factors.

Impact is included in the design of the pier beam and the columns, but not in the design of the foundation if the entire element is below ground.

For girder type superstructures, live loads are transmitted to the pier through the girders. Live loads are transmitted to the girders from the slab using simple beam distribution. Care should be taken not to use the maximum girder reaction (computed when designing the girders) at all girder locations on the pier beam, as this will result in unrealistically high live load reactions.

For slab type superstructures, the truck and lane live load is applied to the pier without transverse distribution. The truck load is applied as a concentrated load and the lane load is applied as a uniform load. The reaction at the pier computed using the live load distribution factor (E) needs to be factored back into a single wheel line reaction.

Piers adjacent to railroad tracks may require a crash wall. See Figure 3.3.4.7-1 Railroad Grade Separation Crash Wall Details for a graphic describing the condi-tions and criteria for use.

(b) Dead Load

Dead loads include the estimated weight of the superstructure (including estimated future wearing surface), the dead weight of utilities and the weight of the substructure.






(c) Breaking Force: Article 3.6.4 Breaking Force (BF) = The greater of: N [640 x BL) + DT] (0.05) (m) or N (DT) (0.25)(m) (BF in lbs.)

N = number of lanes likely to become one directional in future.BL = over-all bridge length (ft.)m = multiple presence factor (Article 3.6.1.1.2)DT = design Truck or Tandem

This force is meant to simulate the forces caused by vehicles braking or accelerating. It is to be applied 6 ft. above the floor. When this force is applied to free-standing skewed piers, the transverse component (to centerline of pier) is applied 6 ft. above the roadway and the longitudinal component (to centerline of pier) is applied at the bearings.

BF to each pier = BF x Average Span Length Bridge Length

Average Span Length = average length of two spans adjacent to the pier under consideration.

(d) Wind Loads:

Wind loads are divided into three types; (1) wind on live load, (2) wind on superstructure, and (3) wind on substructure.

Wind loads include transverse and longitudinal loads which may act on both the piers and the superstructure including wind load on bridge mounted signs and on live loads.

For most usual girder and slab bridges use the wind loading as specified in Article 3.8.1.2.

(e) Temperature

Use method A for calculating Temperature Ranges. See LRFD Section 3.3.4.4 for usage and considerations of thermal force effects. The change in length of the superstructure and pier cap due to temperature changes causes deflections in the columns. These deflections result in moments in the columns. The magnitude of the design moment will depend on the amount of deflection, length and size of column and the fixity assumed at the column ends. See Appendix B Example Calculations: for stresses in monolithic piers due to thermal forces.




For continuous structures with the pier columns monolithic with the superstructure, there is a neutral point on the bridge which does not move when the temperature changes. This point needs to be determined either by examination or by trial and error taking into account column stiffness.

For a continuous structure resting on bearing devices, the maximum longitudinal load an expansion bearing device can transmit to the pier is the friction force. If the longitudinal force exceeds the friction force, the excess is transferred along the bridge to a fixed support.

The friction force acts parallel to the direction of movement and is assumed to act at the bearing elevation at each expansion bearing.

For friction-type bearings, the longitudinal force is given by:

ks x DL where: ks = Coefficient of frictionDL = Deadload reaction on the bearing

The following values for ks shall be used:

Metal-on-metal sliding bearings 0.20Bronze sliding bearings 0.10Teflon-Stainless Steel Table 14.7.2.5-1

For rocker bearings, the longitudinal rolling and sliding resistance is given by:See Figure 3.11.5.9-1 below for further information

where: DL = Dead load reaction on the rockerr = radius of sole plate pin (in.)R = Radius of the rocker (in.)

The above formula assumes a sliding friction coefficient of 0.20. Use this value when determining the force transferred to the bolster (fixed) pier. This low friction value (0.2) assumes the rockers are new and will transfer the maximum force to the bolster pier. For computing the friction force transferred to expansion piers, a sliding friction coefficient of 0.5 to 0.8 may be assumed to simulate rockers which have, over time, become rusty and partially frozen. Again, this will give the maximum force which can be expected in the expansion piers.

DL 20r 2+ 100R

----------------------



Figure 3.11.5.9-1



When elastomeric bearings are used, the longitudinal force is given by:

G x A x Delta/T

where G = Shear modulus (psi) A = Plan area of the bearing (in.2)

Delta = Longitudinal shear deflection in the bearing (in.)T = Total elastomer thickness of the bearing (in.)

The shear modulus G, varies with durometer, temperature and time. Use the maximum value permitted based on a durometer of 60. See Table 14.7.6.2-1 for shear modulus values.

The thermal force on a fixed pier is the resultant of the unbalanced forces acting on all the substructure units. For cases where the unbalanced frictional force is equal to zero, the fixed pier shall be designed for at least the total longitudinal force applied to an expansion pier.

In some cases, it may be cost effective to use isolation bearings to control the transfer of forces to the substructure. Isolation bearings are similar to an elastomeric bearing with the addition of a lead core. By varying the size of the lead core and the overall rubber height, the designer can manipulate the distribution of horizontal forces to the substructure thus achieving reduced column and foundation design forces. See AASHTO “Guide Specifications for Seismic Isolation Design”, June 1991.

(f) Seismic See LRFD Section 3.3.4.8 and Section 3.5.1.6.3 for seismic detailing and loading

All of Kansas is located in the Seismic Zone 1 which means no detailed seismic analysis is required for bridges in Kansas. However, connection to the superstructure from the substructure must be designed for specified forces and must also meet minimum bearing support length requirements. The force effects from accelerations must be transmitted from the superstructure to the foundation through the anchorages. The connections between the footing and the column and the column and the pier beam must be detailed accordingly. See Article 3.10.9.2for information on Zone 1 force effects.



http://www.ksdot.org/burDesign/bridge/lrfd/LRFD_3_5_1_CastInPlace_Concrete1.pdf


(g) Ice Pressure

In the absence of more precise data, the following shall be used as minimum design criteria:

1) Ice pressure is 150 psi.

2) Ice thickness is 1ft..

3) Location of force on pier shall be midway between the ordinary high water elevation and the elevation at Q100.

Ice loads would normally not be considered except on larger rivers such as the Kansas or Missouri Rivers. The need to include ice pressure in the design of a structure should be made at the field check.

(h) Drift

Piers located in streams which are susceptible to transporting large amounts of drift and debris shall be designed to withstand the corresponding increase in stream pressure due to drift accumulation on the pier. The amount of drift build-up is a matter of judgment, but as a guide, the size of the drift may be approximated as follows:

(1) The drift width may be assumed as 10% of each span length contributory to the pier, but no less than 10 ft. nor greater than 45 ft.

(2) The vertical depth could extend from the flow line to the computed high water elevation.

An estimate of the amount of drift to be expected should be discussed at Field Check.

The stream flow pressure can be calculated by P = CDV2 /1000 (Article 3.7.3) with CD = 1.4 for drift lodged against a pier.

Blockage of the flow area by drift build-up can increase the stream velocity and thus increase the scour depths through the bridge opening.

(i) Scour



Scour is not a load per se, however by changing the conditions of the channel its effects need to be considered in the design of the substructure per Article 2.6.4.4.2. The bridge should be fully functional while in a scoured condition for all Load Combinations when subjected to a 100 year flood or less. Check the 100-year flood, the overtopping flood (if less than the 100-year flood) and other events if there is evidence such events would create deeper scour than the 100-year or overtopping floods. Use strength and service combinations for the Design Flood per Article 3.7.5

When checking the effects of a 500 year flood, the bridge should survive the effects of stream flow, dead load, live load and wind load while in a scoured condition. Consider the Extreme Event for the Check Flood without the ice load when investigating this situation.

Stream forces shall be applied to a depth based on the scour evaluation. When checking the lateral resistance of the piling or drilled shafts, no lateral support from the soil above the estimated scour line shall be assumed.

See LFD Section 2.3.9.3 Scour Analysis for further discussion on scour.

(j) Vehicular Collision Force (CT)

Vehicular impact will be considered for all structures within the clear zone and not as stated in Article 3.6.5 which refers to”... 30.0 ft from the edge of the roadway...” See Appendix A Structure Protection Guidelines for KDOT policy on (CT) force effects. Exemption(s) for CT Vehicular Collision Force Article 3.5.1 will not be used when the owner deems the structural as critical.

(k) Dynamic Allowance

Do not apply the Dynamic Allowance (IM) to lane loads, pedestrian loads or to foundation elements which are buried. Use a value of 33% for all limit states other than fatigue per Article 3.6.2.

(l) Centrifugal Force

This force effect applies only to structures which have radial forces. The Centrifugal Force (CF) will be applicable for horizontally curved bridges according to Article 3.6.3.


http://kdotweb.ksdot.org/KDOTOrg/BurDesign/BridgeOffice/2013_BD_Manual.pdf


3.11.5.10 Application of Loads

Longitudinal forces transmitted from the superstructure to the substructure shall be as specified by AASHTO in magnitude but applied through the hinge at the bearing.

Transverse forces shall be as specified by AASHTO both in magnitude and points of application.

When piers are skewed, transverse and longitudinal superstructure forces are converted to transverse and longitudinal forces of the pier by using the sine and cosine functions of the skew angle.

3.11.5.11 Pier Frame Analysis

When computing pier loads and moments, the designer is required to make a number of assumptions and approximations based on engineering judgment.

When computing loads and moments, one important assumption to be made involves the degree of fixity for foundation conditions.

Columns which are assumed fixed at both ends are very effective in resisting horizontal forces; however, these relatively stiff columns will absorb a large proportion of the unbalanced moment. In addition, movements due to temperature and shrinkage can introduce large moments in the columns. Assuming columns fixed at the bottom with the top being integral (fixed) with the superstructure, can lead to design error because a small rotation of the footing will relieve the moments in the columns.

Assuming the bottom of columns hinged in a continuous frame reduces the stiffness of the columns with a corresponding reduction in temperature and shrinkage column moments.

In general, the following is recommended for foundation fixity in lieu of a sophisticated analysis.

1) Spread footing on competent rock: 100% fixity (fixed)

2) Footing on pile:

a. With top of pier integral with superstructure = 0% fixity (pinned)b. With top of pier hinged at superstructure or free-standing pier = 100% fixity

(fixed)

3) For piers constructed integrally with footings and skewed more than 10, the bottom of columns shall be considered fixed.

The pier is analyzed as a frame bent by the available analysis procedures considering sidesway of the frame due to loading.



3.11.6 WallsThe following 3.11.7 Wall Policy outlines policy concerning the review and acceptance of various earth retaining structures and noise or sound walls.

3.11.6.1 MSE Design Considerations

Panel Size:Pursuant to the principle of considering an MSE wall to be a flexible structure, KDOT has adopted a size limitation for the wall panels. The size limitation will allow the expected deflec-tions/movements to occur over a “finite” element and reduce the potential for panel cracking. KDOT has adopted two classes of panel sizes: “L” and “B”. Class “B” panels are limited to an area of 50 ft.². Class “L” panels are limited to a maximum size of 35 ft.². The maximum panel height is limited to 5 ft.. The Designer is required to specify the panel size on the plans. In gen-eral, walls with expectations of moderate to high settlement or movement will require Class “L” panels. The KDOT Geotechnical Report will recommend the panel size.

Utilities:Do not allow utilities and drainage structures in and under the structural backfill zone of MSE walls positioned parallel to the wall face. For storm drainage structures positioned below and per-pendicular to the wall system use the following commonly asked questions as a guide.

Q: For storm drainage pipes positioned below and perpendicular to the wall system, what is the desired cover between top of pipe and bottom of select granular backfill of the MSE wall? What is the minimum cover?

A: The minimum is 24 in. below the bottom of the reinforced soil which is equivalent to 18 in. below the leveling pad.

Q: Is there a special backfill and compaction requirements for the pipe trench which is in the foundation for the MSE system?

A: Compaction in the pipe trench is 95 percent Standard Proctor Density (Type AA) with a mois-ture range of 5 percentage points above to 5 percentage points below optimum (MR 5-5).

Q: Does KDOT allow any storm pipes within the reinforced soil zone, traveling parallel with the MSE wall.

A: No.

Q: Is it permissible to have storm pipes within the reinforced soil zone if positioned perpendicular to the wall?

A: Yes.



Rails:Railings should not be set directly on retained earth structures. Either set the railing inside the wall or put a compressible material between the top of the wall and the bottom of the railing. MSE walls used in conjunction with railing subject to vehicle impact shall be designed to withstand a horizontal force of TL-4 loading distributed according to AASHTO Specifications. The maxi-mum cantilever height above the earth reinforcement for top panels is 3.5 ft. including the coping.

Compatibility:Designers are cautioned whenever a MSE wall is adjacent to a hard structural member (abutment, footing, etc.). It is best to avoid this situation. Avoid tying the MSE footing, the wall, or a wall cap to unyielding members. The MSE wall will eventually settle and crack anywhere it is tied to or sitting on an unyielding member. One solution to the differential settlement issue is to provide a slip joint in the wall between the yielding and unyielding members. See Figure 3.11.6.1-1 MSE Retaining Walls (integral abutment < 2” of movement).

Horizontal Movement:When an MSE wall is used to retain fill at an abutment, the MSE wall should be a minimum of 5 ft. from the centerline of the abutment pile. This will minimize passive pressure on the wall from the pile movement (temperature translation). See Figure 3.11.6.1-1 MSE Retaining Walls (integral abutment < 2” of movement). Use modular block type MSE walls near integral abutments. Using a wall facia with many smaller joints will accommodate movements better than panel type walls will fewer joints. The following guidelines are to be used when choosing abutment type:

• Integral abutments will be used for bridges with less than 1in. total thermal movement. • For bridges with a total movement between 1in. and 2 in. use integral with an isolation casing

sleeve with a cap, back fill the piles with sand but leave 10 ft.-15ft. of the top unfilled per Figure 3.11.6.1-1 MSE Retaining Walls (integral abutment < 2” of movement).

• For bridges with total thermal movement between 2 in. and 5 in. use a semi-integral per Fig-ure 3.11.2-5 MSE Retaining Walls (Semi-integral abutment < 5” of movement).

• For bridges with movements greater than 5 in. use a free-standing abutment and a finger plate expansion joint.

Vibrations:When an MSE wall is used to retain fill at an abutment, it is KDOT’s practice to drive abutment piling before the MSE wall is constructed. Pile driving vibrations after MSE construction may significantly consolidate the structural fill of the MSE wall.

In some cases it may be necessary to drive abutment piling after the wall is completed, this is not recommended, a corrugated metal pipe (CMP) sleeves around the piling are recommended to pro-tect the straps (reinforcing) of the MSE wall. See Figure 3.11.6.1-1 MSE Retaining Walls (inte-gral abutment < 2” of movement).

Downdrag:



At locations where downdrag forces on the piling are noticeable due to foundation settlement (Note: read the Geotechnical Report) or where settlement may occur from pile driving in different stages of staged construction, the piling should be coated with bitumen to reduce side friction. As an alternate, the piling may be “sleeved”, the piling in those conditions should be reviewed for performance of lateral movement (temperature) and unsupported length.

Backfill Limits:Where the plans and Geotechnical Report require the wall to be constructed on fill, (generally fill with specific strength requirements) note the limits of the special foundation soils on the MSE wall details. The Road (earthwork) x-sections will show the same limits. In some locations, simi-lar soil placement may be required behind the structural fill mass. Note these locations in the MSE wall details and in the cross-sections.

Drainage:In locations where drainage problems are anticipated or are of concern, use modular block type MSE facia. Modular block will drain through the wall and do not require interceptors.



Figure 3.11.6.1-1 MSE Retaining Walls (integral abutment < 2” of movement)



3.11.6.2 Earth Retaining Structures Review and Acceptance Proce-dures

3.11.6.3 PurposeThe purpose of these review and acceptance procedures is to establish policies, practices and responsibility for the preparation and review of plans, design and construction control of earth retaining structures.

3.11.6.4 GeneralInformation furnished by FHWA concerning application of the various earth retaining structures should be considered as reference material in the selection of an appropriate system. Prefabri-cated wall systems (proprietary or generic) should be included in competition with conventional reinforced concrete retaining walls where considered appropriate. In considering the use of pro-prietary walls, the Designer should, when requested, provide assistance to a wall supplier of an approved system which can attain the project objectives. Special Provisions for earth retaining structures will require proprietary wall suppliers to provide a qualified and experienced represen-tative on the project site to assist the Contractor at the start of wall construction. For the duration of construction of the project, the representative will be available on an as needed basis, as requested by the Engineer.

3.11.6.5 Initial System ApprovalDue to the recent development of so many different types of earth retaining systems, consider-ation of alternates is required prior to preparation of contract documents so Contractors may be given an opportunity for bidding to provide a satisfactory cost effective system. A proprietary sys-tem must have Departmental approval prior to inclusion as an alternate during design phase.

The criteria for selecting and placing a system and the supplier on the approved list by the Bureau of Structures and Geotechnical Services is based upon the following considerations:

1. The Supplier’s scope of operation is adequate to supply the necessary wall components and documentation on time.

2. The system has a sound theoretical and practical basis from an engineering evaluation.

3. Past satisfactory installations and performance of the proposed system.

In addition, the Supplier or his representative, must submit back-up material to include the following:

(A) System theory and the year it was proposed.(B) Where and how the theory was developed.(C) Laboratory and field experiments which support the theory.(D) Practical applications with descriptions and photos.



(E) Limitations of the proposed system.(F) List of owners including, names, addresses and phone numbers.(G) Details of wall elements, analysis of structural elements, design calculations,

factors of safety, estimated life, corrosion design procedure of soil reinforcement elements for the proposed environment, procedures for field and laboratory evaluation including instrumentation and special requirements.

(H) Sample material and construction control specifications including material type, quality, certifications, field testing, acceptance and rejection criteria and placement procedures.

(I) A well documented field construction manual describing in detail, with illustrations where necessary, the step by step construction sequence. (Copies of this manual should also be furnished to the Contractor and the Project Engineer at the Pre-Construction Conference for the selected wall.)

(J) Typical unit costs, supported by data from actual projects.(K) Details of typical system designs for copings; and for conduits, manholes, and

light tower footings through the structural fill mass.

After the above material is submitted, a thorough geotechnical and structural review will be per-formed concerning the design, construction practicality and whether or not the system would be appropriate for the particular project.

3.11.6.6 Wall Selection Considerations(A) In addition to initial construction and future maintenance cost, problems associated

with the eventual replacement should be considered.(B) The influence of construction time may also be a consideration on the overall

project.(C) Aesthetics may also influence the selection of a particular wall.(D) Consultants or the Bureau of Structures and Geotechnical Services should consider

only feasible alternates and provide at least two alternates whenever feasible.

3.11.6.7 Economic Considerations for Wall SelectionThe selection of a particular retaining wall for a specific project requires consideration of both technical feasibility and comparative economy.

Factors which must be considered with respect to economy are as follows:(A) Concerning the cost of construction of the wall proper--

1. Cut or fill earthwork situation.2. Size of wall area.3. Average wall height.4. Foundation conditions (i.e. would a deep or shallow foundation be

appropriate for a cast-in-place concrete retaining wall).



5. Availability and cost of select backfill material.

(B) Concerning the cost of items influenced by the selection of one wall over another--

1. Cost of right-of-way required.2. Size of wall area.3. Requirements for temporary excavation support systems.4. Maintenance of traffic during construction.

3.11.6.8 Plan Preparation RequirementsInformation to be furnished by either the Kansas Department of Transportation or Consultants for KDOT to retaining wall suppliers for preparation of plans, is listed below.

(A) Geometric

1. Beginning and end of wall stations.2. Elevation on top of wall at beginning and end of wall. Include profile break

points and roadway profile data at wall line.3. Cross sections at the retaining wall locations at 50-100 foot intervals.4. Horizontal wall alignment.5. Details of wall appurtenances such as traffic barriers, coping, drainage

outlets, location and configuration of signs and lighting including conduit locations.

6. Right-of-way limits.7. Construction sequence requirements when applicable, including traffic

control, access, and stage construction sequences.8. Elevation of highest permissible level of foundation construction. Location,

depth and extent of unsuitable material to be removed and replaced.9. At abutments, elevation of bearing pads, location of bridge seats, skew angle

and all horizontal and vertical survey control data including clearances and details of abutments.

10. At stream locations, historic high water and normal water levels.

(B) Subsurface investigation report including specific design values for the following parameters:

1. Foundation materials to include the following properties: consolidation, bearing capacity, allowable bearing values, and shear strength (cohesion and values).

2. Select backfill to include the following properties: unit weight, and shear strength (cohesion and values).

3. Random fill or in situ soil behind wall to include the following property: shear strength (cohesion and values)



(C) Design Requirements

1. Generally, reinforced earth retaining walls would not be economical for wall heights less than 10 ft..

2. For a permanent mechanically stabilized earth wall, the reinforcement elements are to be designed to have an adequate corrosion resistance-durability for a minimum service life of 75 years.

3. Minimum safety factors shall be as follows: 2.0 for overturning, 1.5 for sliding and 1.2 for temporary slope stability.

4. Determination of allowable bearing pressures should consider the flexibility of the retaining system. In general, the minimum factor of safety for bearing of soil foundations should be at least 2. This is the ratio of the ultimate bearing capacity to the allowable bearing pressure in which the ultimate bearing capacity is the maximum bearing pressure the foundation material will sustain without exceeding the shearing strength of the foundation material. Embedment depth and settlement is to be considered in the analysis.

5. Internal design requirements for mechanically stabilized earth wall elements: Allowable reinforcement material stress is 0.55Fy for steel. Safety factor against reinforcement pullout should be 1.5. Pullout resistance should be based upon the capacity achieved at a maximum deformation of ¾ inch.

6. Magnitude, location and direction of external loads due to bridges, overhead signs and lights, traffic surcharge and rapid groundwater drawdown.

7. Limits and requirements for drainage features beneath, behind or through the retaining structure.

8. Backfill requirements for both within and behind the retaining structure. Both material and placement requirements should be specified to include gradation, plasticity index, electrochemical, soundness, maximum loose lift thickness, minimum density and required moisture content.

9. Special facing panel and module finish or color.10. KDOT guidance concerning construction specification requirements or

special provisions.



3.11.6.9 Requirements for Supplier Prepared Designs and PlansThe final design submitted shall include detailed design computations and all details, dimensions, quantities and cross sections necessary to construct the wall. The fully detailed plans shall be pre-pared to according to section 105.10(b), sheets and shall include, but not be limited to, the follow-ing items:

(A) A plan and elevation sheet or sheets for each wall, containing the following:

1. An elevation view of the wall which shall indicate the elevation at the top of the wall, at all horizontal and vertical break points and at least every 25 ft. along the wall, elevations at the top of leveling pads and footings, the distance along the face of the wall to all steps in the footings and leveling pads, the designation as to the type of panel or module, the length, size and number of mesh or strips and the distance along the face of the wall to where changes in length of the mesh or strips occur and the location of the original and final ground line.

2. A plan view of the wall which shall indicate the offset from the construction centerline to the face of the wall at all changes in horizontal alignment, the limit of the widest module, mesh or strip and the centerline of drainage structures or drainage pipe which is behind or passes under or through the wall.

3. General notes required for design and construction of the wall.4. All horizontal and vertical curve data affecting wall construction.5. A listing of the summary of quantities provided on the elevation sheet of

each wall for all items including incidental items.6. Cross section showing limits of construction and in fill sections, limits and

extent of select granular backfill material placed above original ground.7. Limits and extent of reinforced soil volume.

(B) All details including reinforcing bar bending details. Bar bending details shall be in accordance with KDOT Standards.

(C) All details for foundations and leveling pads, including details for steps in the footings or leveling pads, as well as allowable and actual maximum bearing pressures.

(D) All modules and facing elements shall be detailed. The details shall show all dimensions necessary to construct the element, all reinforcing steel in the element, and the location of reinforcement element attachment devices embedded in the facing.

(E) All details for construction of the wall around drainage facilities, overhead sign footings and abutment piles shall be clearly shown.



(F) All details for connections to traffic barriers, coping, parapets, noise walls and attached lighting shall be noted on the plans.

(G) Detailed design computations shall be submitted.

(H) The design parameters used will be found in the subsurface investigation report. The assumptions made in the report will be used in the design of the wall system. Deviations in the design parameters used or changes which will effect the assumptions made, will first be cleared with the subsurface investigation report’s authors.

(I) The plans shall be prepared and signed by a licensed professional engineer.

Two sets of design drawings and detail design computations shall be submitted to the Bureau of Structures and Geotechnical Services. The computations shall include a detailed explanation of symbols and computer programs used in the design of walls. All designs and construction details will be checked by the Bureau of Structures and Geotechnical Services against the preapproved design drawings and procedures for a particular system. Design details and plans shall be reviewed by the Bridge Squad Leader.

3.11.6.10 Materials ApprovalPrior to delivery of material used in the retaining wall construction, the sources must be pre-approved in conformance with the Department specifications.

3.11.6.11 Consultants ResponsibilityThe Supplier shall furnish the Consultant the design calculations and plans for their internally reinforced retaining system. The design plans shall be checked, revised as required and approved by the Consultant prior to inclusion in the plan tracings. The Consultant for a project should coor-dinate with the Bureau of Structures and Geotechnical Services concerning the responsibility for subjects discussed in the next sections.

3.11.6.12 Department ResponsibilityThe following sequence outlines the organizational unit and necessary actions by the unit to select, coordinate and review designs and monitor construction of earth retaining structures.



SYSTEM APPROVAL FOR SPECIFIC PROJECTS

ORGANIZATIONAL UNIT RESPONSIBILITY AND ACTIONGeotechnical Section 1. Reviews geotechnical aspects of wall sup-

plier submittal and provides formal com-ments and recommendations to Bridge Design Section.

Chief, Bureau of Materials andResearch

2. Notifies wall supplier system of Research acceptance or rejection.

Bridge Design Section 3. Reviews structural aspects of wall supplier submittal and provides comments and rec-ommendations to the Bureau of Structures and Geotechnical Services.

WALL SELECTIONBureau of Structures and Geotechnical Services

1. Determines need for an earth retaining structure at a specific location

Bridge Design Section 2. Requests geotechnical report, subsurface investigation and wall selection recommen-dations from geotechnical section. Project designer should advise Geotechnical Sec-tion of particular project constraints, spe-cific site conditions, environmental or aesthetic conditions.

Geotechnical Section 3. Perform subsurface investigation, labora-tory analysis/testing and prepares project foundation report. The report should include:

A. Interpretation of subsurface conditions. B. Recommendation of appropriate wall

types for subject foundation conditions. C. Indication of materials and conditions

which may be encountered during construc-tion.

D. Possible design and construction prob-lems and recommendations for their solu-tion.

E. Special notes which should be placed on the plans or special provisions.

F. Reasons and supporting data for recom-mendations.



3.11.6.13 Sound/Noise WallsThe need for noise walls on or adjacent to bridge structures must be approved by the State Bridge Office and justified by the results of an environmental assessment. Please refer to APPENDIX G ENGINEERING POLICY. The “Noise Abatement Policy” has been in effect since August 1996. This is a general policy and Noise Abatement report recommendations exceeding these limita-tions have been followed in the past, but an effort should be made to identify and document the locations where these height limitations will be violated. This documentation should be sent to Environmental Section for their review and comment

Noise walls mounted on Bridge Structures over highway or railroad traffic will be designed to resist Vehicular Collision Forces in Article 15.8.4 loading conditions using an LRFD extreme event limit state with barriers and connection to barriers analyzed by methods with sufficient degrees of freedom.

Noise walls placed on Bridge Structures which can fall onto traffic lanes or shoulders from above, as in the case of when a noise wall is mounted on the bridge over a grade separation, will have

Geotechnical Section 4. Based on geotechnical report and recom-mendations, cost estimates and aesthetic considerations, selects appropriate wall design alternates. If appropriate, procedures as outlined in Sections 3.11.6.3 through 3.11.6.10 of this document should be fol-lowed. Coordinate preparation of the plan with the Geotechnical Section as outlined in Section 3.11.6.8 of this document.

FINAL PLAN REVIEWBridge Design Section 1. Review structural aspects of earth retaining

structure submittals in accordance with Sec-tion 3.11.6.9 Requirements for Supplier Prepared Design and Plans.

Geotechnical Section 2. Review geotechnical considerations of earth retaining structure submittals in accor-dance with Section 3.11.6.9, Requirements for Supplier Prepared Design and Plans.

CONSTRUCTIONBridge Design Sectionand Geotechnical Section

1.Provide technical assistance to project construction personnel prior to and during

retaining wall construction (preconstruc-tion meetings, construction problems, eval-uation of new or unusual systems).

Construction Project Engineer 2.Provide construction supervision and inspection. Immediately notify bridge and geotechnical section of construction prob-lems.





fully restrained elements and connection to the parapet designed for Extreme Event II loading conditions. Noise walls placed adjacent to Bridge Structures which can fall into traffic or shoulder lanes will have continuity elements included in the design.

Noise wall taller than 10’ present inspection problems when they are mounted on bridges and therefore, it is not recommended unless prior agree by the Bureau of Structures and Geotechnical Services.

If the noise wall is mounted on a structure use a 110 mph wind speed. For ground mounted noise walls use Figure 15.8.2-1 for wind speed determination.

Noise wall mounted on top off MSE walls will be supported by drilled shafts set behind the face of the wall at least four shaft diameters. Use only modular block type walls (MBW) for this appli-cation. KDOT has performed extensive research which shows the performance of MBW with lat-erally loads drilled shafts in the reinforcement zone, and therefore, have a high level of confidence with the performance of these wall systems.

Minimum Criteria for noise walls mounted on top of MSE wall:

The top of drilled shaft, for noise walls mounted on top of MSE walls, will have movements lim-ited to 1”(in each direction) and the lateral loads must be resisted exclusively by the drilled shafts. The mobilized soil pressures resisting the shaft rotation must resist all lateral load applied to the noise wall. The retaining wall facing elements and MSE wall reinforcing should not to counted on to provide resistance to the lateral loading. The shaft length and diameter should be adequate to limit the deflection and to transfer the load to the soil mass.

Wind Load 50 #/sq. ft.Max. Height 20 ft.Max. Shot Spacing

15 ft.

Min. Shot Length

15 ft.



WALL POLICY

3.11.7 Wall Policy

INITIAL WALL LAYOUTWall design and layout is a multi-disciplinary process involving, as a minimum, the Geotechnical Section, Road Design Section and Bridge Design Section. In addition, many other functional units within the agency may have input regarding use of these structures. The Project Manager (The Bureau of Road Design or Consultant) coordinates with all of the design units involved in a proj-ect.

When the need for a retaining wall or noise wall has been identified, the Road Design Leader and their staff (or KDOT’s consultant) is responsible for establishing the preliminary geometric layout of the walls. The layout includes identifying the alignment of the wall, providing a profile along the planned ground line at the face of the wall, a profile of the planned top of wall elevation, cross-sections detailing the wall and the physical features within the wall influence zone which may impact the wall design, construction and performance.

Types of walls covered in this policy:

Retaining walls Noise walls Wall combinations

GENERAL GUIDELINES FOR DESIGNWall location and design is influenced by many factors and features. Some of these include but are not limited to:

Walls will be considered individually and as a system of inter-related wall systems or wall combi-nations (some wall systems are multi-tiered or are a combination of retaining and noise walls). All walls are influenced by some of the variables listed above and by the interaction between

• Geometric Constraints • Signing and Lighting• Right-of-Way • Signals and Controls• Structural Requirements • Detection equipment needs• Geotechnical conditions • Environmental issues• Constructability • Noise mitigation requirements• Drainage • Safety requirements• Drainage Structures • ADA accommodation • Guard Fence or Barrier • Wall design life• Utility Accommodation • Foundations for other structures or

walls



these variables. Therefore, each wall layout will also show an associated typical section(s) and actual plan and elevation views of the planned wall and its location with respect to the other fea-tures which may influence the alternatives to be considered. It is imperative to detail all known interactions of these many elements to prevent costly modifications during construction. Road and Bridge Staff will coordinate the alignment and profile development for each wall and conduct careful reviews for conflicts with existing or planned features.

WALL TYPES

Retaining Walls

Mechanically Stabilized Earth (MSE) wall systems are typically constructed with one of three facing systems: Modular Block, Reinforced Concrete Panel or Welded Wire Facing. Most facing and soil reinforcements are proprietary systems designed to be flexible in nature. Plan details are developed by KDOT’s structural design staff in coordination with KDOT’s Geotechnical Unit and Road Design staff.

Cast-In-Place (CIP) walls are typically considered to be a structural design feature since both external stability and structural strength or internal stability will satisfied. The details are devel-oped by KDOT’s structural design staff or design consultant. In all other respects the design must be coordinated with both the Geotechnical Unit and Road Design staff. The practice of develop-ing separate detail sheets (as with other wall types discussed above) is appropriate. Where included in projects with other retaining wall systems, it may be appropriate to include cast in place wall quantities on the summary sheets with other walls.

Noise WallsNoise walls generally require more structural engineering expertise than MSE wall systems. Another principal difference in the development of noise wall details is the determination of the location of these elements, i.e. noise wall locations are based on the need, as determined by the Environmental Section, to provide noise abatement measures. See Appendix D Noise Abatement Policy for KDOT Noise Abatement Policy. Noise wall alignment, height and profiles are accom-modated in the design process in a manner similar to retaining walls and are therefore included in this wall guide.

Noise walls when extending onto bridges over traffic should have a detailed noise analysis per-formed by a qualified specialist to document the impacts to local receivers if the wall were not placed on the bridge. From this detailed analysis a decision can be made as to whether the wall should be extended across the bridge. When extending noise walls on bridges which extend over traffic, the wall element and connection to the barrier will be evaluated for TL-4 vehicular impact. Bridge inspection access equipment is severely limited if the wall is over 10 ft. in height, mea-sured at the bridge barrier. Placing noise walls on bridges over streams can impact the ability of Bridge Management to perform in-depth inspections and should be considered in the develop-ment process.



Landscape WallsLandscape retaining walls, as defined by KDOT, consist of wall systems meeting all 5of the fol-lowing requirements:

• A total height less than 6 ft. measured from top of footing to top of wall profile at all points along the length of the wall.

• The maximum live load surcharge of 100 pound per square foot is not exceeded.• The slope of the material retained by the wall does not slope toward the wall at a rate of 6:1 or

steeper within the area 6’ behind the wall.• The wall is not a part of a multiple tiered wall, which as a system would have a total height

greater than 6ft..• Loss of life, serious loss of function or access to adjacent necessary services/structures, or

significant property damage is unlikely in the event of failure.

The development and design details of these walls are different than other wall applications. A geotechnical investigation is not required. Design staff will prepare details showing the align-ment, top of wall profiles and typical section views, etc. These walls are not considered to have the potential for high risk to public safety; therefore they are not numbered, tracked or inspected following construction. Landscape walls typically consist of modular block or cast in place con-struction.

Refer to the memo on: Appendix E Landscape Retaining Wall Policy Revision 1

WALL DATABASE

The Project Manager will request a Wall Serial Number for each wall except Landscape Walls. The Bureau of Structures and Geotechnical Services maintains the data base which contains infor-mation on all walls other than Landscape Walls and all walls attached to bridge barriers. Consult the Bridge Sections Management Systems Analyst for the correct number. Assistance is available if needed. See Attachment #1 for the Serial Number request form. See Attachment #5 for wall type abbreviations used for serial number requests and construction plan notes.

WALL DEVELOPMENT PROCESS

The Road Design Leader will coordinate with the KDOT functional units involved in a project. Bridge Section staff will be responsible for some portions of the project development process when retaining walls or noise walls are planned as part of a project. When the need for a retaining wall or noise wall has been identified, the Bridge Squad assigned to the project and the Geotech-nical Unit will be included in the coordination needed for plan development. In the early develop-ment of the wall layout concepts, the Bridge staff and the Soils Section gives input concerning type, size, location, structural viability and cost of the proposed solution.

The transmittal of plans at this stage of project development, “Plans to the Bureau of Structures and Geotechnical Services”, is intended to focus on surface geology and those features which are needed to help define right-of-way requirements (vertical cuts, benching, maximum cut or fill slopes, etc.). A study of the “surface geology” early in the project development may provide



opportunities to minimize right-of-way requirements without the use of retaining structures. Identification of problem soil conditions and settlement issues, or other unforeseen subsurface conditions are usually not known at this stage. When factors such as traffic accommodation, high cost right-of-way, environmental constraints, noise study findings, community involvement and other influences result in the need to incorporate walls, it is important to begin to factor these items into project costs, resource requirements and project schedules.

If retaining walls are needed, the Soils Section of the Geotechnical Unit and Bridge staff will determine the wall type. Wall systems include Cast-In-Place (CIP), Modular Block (MBW), Mechanically Stabilized Earth (MSE), or other wall types. Careful consideration should be given to special construction techniques, such as “top down” construction and “tie-back” supported walls. Geogrid reinforced embankments are not considered to be walls and are not addressed in this policy; however their presence may influence wall design. The use of “soil nails” and “rock anchors” or other special embankment stabilization techniques are not included in this policy.

As alternatives are considered, public involvement may influence the decision process. Generally this relates to the use of noise walls and the aesthetic qualities of walls being constructed in their communities. Constructability issues must also be addressed.

Prior to field check, the wall layouts will be shared by Road staff to coordinate the layout with other adjacent features such as bridges, drainage structures or other walls. Adjustments in the wall alignments and profiles should be expected as the details are developed. The Project Man-ager will request serial numbers for all walls requiring them.

Based on the recommendations from the Soils Section, Design staff will confirm and finalize wall locations to proceed to field check. After field check the Bridge Squad Leader will request a Retaining or Noise Wall Investigation by the Soils Section. This request will be based on the final location of all wall structures as documented in the field check plans. The Soils Section will pro-ceed with the retaining wall investigations to determine the wall design parameters and to verify the external stability of the proposed wall system. The wall location should be finalized by field check, but if changes to the alignment or profile of the wall do occur, the Road and Bridge Sec-tions must convey this information to the Soils Section in a timely and complete manner.

The responsibility for providing the details in the final plans for each wall will be determined by the Road and Bridge staff on a project-by-project basis. In general:

• The Bridge Section is responsible for retaining wall systems connected to or adjacent to bridge elements. The Road Section addresses geometrics, drainage and utility coordination.

• Landscape retaining walls will be the responsibility of the Road Section. The Bridge Section will assist with any structural engineering which is required.

• Noise walls are generally structural in nature. The Bridge Section will be responsible for most of the design and details; however the Road Section must identify the preferred loca-tion, alignment and profile for the walls. Noise wall design is influenced by the location of the controlling noise source in reference to the location of the impacted receptors. Based on an identified location for a noise barrier, the height of wall is determined (See Appendix D



Noise Abatement Policy ) and the roadside geometrics are completed. Plan sheets and details needed to define the wall are similar to retaining wall systems, but in the case of noise walls, the supports for the walls are the key elements which must be located and structurally designed.

FIELD CHECKStructural concerns regarding walls will be discussed and documented during the Bridge Field Check. These include, but are not limited to which are attached to the bridge, support the bridge berms or those which abut or straddle other structures.

The Field Check memo will address issues associated with walls. These issues will be docu-mented on large projects in the Wall Field Check Report.

Use the assigned wall Serial Number to reference all walls in the Field Check Report.

Subsequent to the field check, the Road Design or consultant design staff will assist in the prepa-ration of Wall Field Check Templates Attachment #2 for each wall on the project. Attachment #3 addresses wall stationing. Bridge staff will help in development of the reports. The Wall Field Check reports (one for each wall), if used, will become part of the Field Check Memo(s).

The Bridge Section will assume responsibility for all walls other than Landscape Walls after Field Check. This includes communications with the Project Manager, the Consultant, and Soils Sec-tion. This also includes projects which do not have bridges in the scope. It is critical to have all members of the design team inform the Bridge Section of changes or problems as these projects progress.

After field check the Bridge Section will request a Geotechnical Investigation for both Soil parameters and foundation recommendations. KDOT Geotechnical Section will provide founda-tion recommendations for all walls.



TYPICAL PLAN DETAILSThe following list has been developed to provide the designer with a checklist of details typically provided when a wall is to be included in the plans. It is not considered to be all-inclusive.

These are example sheets only. The designer should add missing information and remove extra-neous data based on their project. The information shown may not be the latest approved.

Sheet Numbers for the designer’s reference are in parenthesis following the sheet title.

Note: Sheets are assigned to a work unit. Most sheets require collaboration. This table attempts to define content and primary responsibility.

Sheet DescriptionRoad Title Sheet (0) – “Walls” will be included in the scope on the title sheet.Road “Retaining Wall & Noise Wall Layout” (2) providing wall number, base-

line, station and offset to both ends of the wall, overall wall length and wall type (See Bridge Manual for listing of acronyms.) as well as an index to wall drawings.

Road Summary of Retaining Wall and Quantities (3) listing all retaining walls on the project. Include notes which clarify the basis of measurement and basis of pay for the wall itself and the basis for estimating the select granular backfill volumes which are subsidiary. The basis of payment and measure-ment shall be shown for the geomembrane and all additional subsidiary items shall be called out.

Road Retaining Wall & Noise Wall Layout (1) for large projects where numerous walls are proposed or where the sheet will be of help in orienting the plan user to the general location of the various walls within the project. This sheet is for general reference, but should accurately depict the location of the walls as related to the baseline geometrics of the project. At a mini-mum, each wall should be labeled with its Serial Number.

Road Retaining Wall General Notes (4, 5) for each retaining wall system included in the plans. Included in the plans are the approved system sup-pliers for each retaining structure as detailed in the Report of Retaining/Noise Wall Investigation. Design criteria, design loading, geotechnical parameters, safety factors, construction requirements and numerous other requirements must be included in the plans or specifications. These requirements are the foundation upon which the system providers will develop their wall design. The General Notes sheets or the specifications must provide this information.



Bridge Summary of Design Soil Parameters (6) providing bearing capacities and design properties for the retained fill, foundation soils and special fill to be used by the wall manufacturers in developing the final wall design details. Other specific construction and scheduling requirements called out in the Geotechnical Unit’s “Report of Retaining/Noise Wall Investigation” will also be noted on this sheet.

Road Common Retaining Wall Details (7, 8) includes details of items which are common to all of the wall locations of a specific type. These are details regarding drainage within the retained fill, compaction requirements for any special foundation fill required, placement of the geomembrane and the protective cushioning material, minimum embedment of the concrete leveling pad below ground line, placement of joint filler adjacent to the cast-in-place concrete coping, slip joint details or other features which need not be repeated from wall to wall.

Road Legend - Retaining Walls (9) (if appropriate) is a table or chart explaining the symbols used to represent information on other drawings.

Road Retaining Wall Plan & Elevation (10, 11) for each individual wall. This sheet will depict the plan view, horizontal alignment details and the eleva-tion view of the wall, a typical section should be shown (Geologic forma-tions requiring special treatment should also be shown.). A wall baseline will be established for each wall. Alignment notes and ties to an appropri-ate project centerline, baseline or other reference line will be provided on this sheet. Ties from the ends of the wall to an appropriate project baseline will be used to reference, station and number the walls. The serial number is assigned by the Bridge Section (See “Wall Database” Section) for the purposes of tracking and maintenance inspections following construction. As described in the number guide, landscape walls will not be assigned a serial number. “Retaining Wall Plan & Elevation” will include a construct note (three sided box) referencing the wall by station, offset, wall type and serial number on the plan portion of the sheet.



Noise wall plan development is similar to developing drawings for retaining wall systems. Gen-erally noise wall systems require more structural design than retaining wall systems. The Bridge Section will be responsible for these sheets following field check and will make all requests to the Geotechnical Unit. The Project Manager will be responsible for the development of the initial plan profile through field check and will conduct all presentations to the public dealing with the proposed noise wall concepts.

Road Retaining Wall Typical Section Details (12, 13) are a more detailed typical section for specific walls on the project. These sheets provide further details regarding foundation, drainage, controlling clearances, slopes, etc. The typical section should depict the typical excavation / embankment details such as the location of retained fill and select fill, the basis of the quantities estimated in the plans and, if not covered by a standard specifi-cation or special provision, identify items which are considered to be sub-sidiary. Typical Sections are sometimes needed to depict unique situations along the length of the wall (Noise Wall/Retaining Wall Section shows a combination of a noise wall drilled shaft behind a retaining wall). An out-line of the proposed construction sequence will be provided for each wall detailed. Further, these sequence notes may provide specific time restric-tions such as “time needed for settlement prior to paving operations” if applicable for the wall depicted. Traffic barrier – Refer to Traffic Barrier policy/detail sheets.

Bridge “Miscellaneous Details” drawings” (14) are often needed to detail the interface between walls and structural elements such as abutments sur-rounded by walls, barrier rails, foundations within the reinforced backfill, etc. These sheets are generally of critical importance to both the retaining wall system and the proper performance of the other structural elements.

Road Road Cross Sections” (24, 25, 26) Provide the needed views as well as detailing special considerations such as the influence of, or interface with, drainage pipes and structures. Proper storm drainage interception and dis-charge are important to long term performance of the retaining systems.



Sheet DescriptionBridge Noise Wall General Notes and Index of Drawings (17). Bridge Section

will be responsible for completing and reviewing this sheet.Bridge “Noise Wall Quantities & Foundation Summary (18).

Road Bridge Noise Wall Plan and Profile (23) will include a construct note (three sided box) referencing the wall by station, baseline offset, description and serial number in the plan view. The limits of need should be shown in the profile view and a summary of required steel post lengths and panel sizes should be provided for the fabricators information. Road and Bridge Sections and the Environmental Section must coordi-nate their efforts to assure the details provided adequately address the intended noise mitigation requirements.

Bridge Noise Wall Drilled Shaft Data (19). This sheet will provide a summary of the drilled shafts being used for noise wall foundations on the proj-ect; it will include shaft diameters, shaft lengths, length of rock sockets and the bill of reinforcing for the drilled shafts.

Bridge Noise Wall Drilled Shaft Details (22). This sheet will be provided for noise walls supported on drilled shaft foundations. Similar sheets may need to be developed for special situation involving alternative noise wall foundations such as spread footings or strip footings, etc.

Bridge Noise Wall Drilled Shaft Data (19). This sheet is for noise walls behind mechanically stabilized earth walls. The sheet will provide all drilled shaft design loads along with a summary of design soil parame-ters. The Bridge Section will work with the Geotechnical Unit to pro-vide all information which will be required by the wall manufacturer to complete his design for internal stability of the MSE wall system. This sheet should be referenced on the MSE wall plans.

Bridge ”Noise Wall Concrete Panel Details” This sheet contains the details to be used by the noise wall concrete panel fabricator.

Bridge Noise Wall Structural Steel Details (22) This sheet contains the details for the steel post, base plates, post bracing systems which may be required and the anchor bolts for use by the fabricator of the structural steel noise wall components.

Bridge Miscellaneous Noise Wall Structural Details(22). These sheets pro-vide a sample of possible structural details which may need to be included in the plans. These details may include details for attaching noise wall to concrete safety barriers, additional details for connecting the safety barrier to the shoulder pavement for adequate transfer of the noise wall loads, details for access ports for fire safety and details for various block outs such as drains and sign truss foundations. Traffic barrier – Refer to Traffic Barrier policy/detail sheets.



OFFICE CHECKThe Road Section, the Geotechnical Section and Bridge Section will coordinate the review of plans to identify any errors or omissions. The resolution of these items will also be coordinated.

SHOP DRAWINGS After the project is let, the Contractor will submit the required shop drawing for any fabricated wall system or component.

The Fabricator sends shop drawings for wall systems or components to the Bridge Section and to the Geotechnical Section. They also send shop drawings to the KDOT Consultant if applicable. The Bridge Section or the bridge design consultant is responsible for reviewing the shop draw-ings. This review includes the geometrics, panels, footings, etc. The Fabricator adapts the design to utilize their product within the plan tolerances (minimums, maximums and geotechnical requirements). For example, the Fabricator may lower the leveling pad to a uniform elevation and provide “steps” in the elevation of the pad to fit his panel dimensions. These changes may affect other details such as drainage accommodation or clearance to utilities or sanitary sewers etc. These influences will be addressed in the shop drawings. Review of these changes may require the involvement of the Road Section staff.

The Geotechnical Section reviews the adequacy of the Fabricator’s designs and the geotechnical stability of all walls. When both the Structural and Geotechnical issues have been addressed, the approved shop drawings are distributed.

The Bridge Section distributes the approved shop drawings and accompanying correspondence. (See Attachment #4 for Approved Shop Detail correspondence distribution list). Bridge Design sends a copy of correspondence only (no shop drawings) to Road Design.

CONSTRUCTION ISSUESThe Division of Operations and the Bureau of Structures and Geotechnical Services will work together when there are construction problems.

The District will inform the Project Manager and the Geotechnical Unit if there are construction problems with walls and when applicable, the consultant designers will be apprised of the con-struction issues.

Contact the Bureau of Structures and Geotechnical Services if there are construction problems or questions. Do not contact the proprietary Wall Manufacturer/Fabricator directly if the wall is a Mechanically Stabilized Earth Type Wall. Do not direct Operations staff or Consultants to contact the Wall Manufacturer. The Bureau of Structures and Geotechnical Services will coordinate the appropriate communications with the Wall Manufacturing entity for MSE structures.

Do not develop or implement solutions for wall problems. This may relieve the Wall Manufac-turer of liability. While KDOT solutions may be the correct option; contact the Bureau of Struc-tures and Geotechnical Services first. KDOT may develop solutions, but wait for Geotechnical Services to give guidance.



REVISED PLANSThe District staff will notify the Road Design Leader, the Bridge Designer and Geotechnical Ser-vices of all proposed wall changes. If wall revisions require revised shop drawings, the process of reviewing and distributing the revised drawings is similar to a new submittal.

The Fabricator will submit revised shop drawings. Bridge Design or KDOT’s Consultant will review the structural acceptability of the shop drawings. Materials and Research will re-evaluate the MSE wall shop drawings for adequacy of geotechnical design.

Bridge Design will distribute the approved revised shop drawings as per their normal practices. (Attachment #4)

The Road Project Manager will revise and distribute revised wall plan sheets following normal revised sheet procedures. The Bridge Section will revise and distribute revised plan sheets for walls affecting elements of the bridge system. (Sheets are assigned to Road or Bridge based on the original author. See the preceding section title “Typical Plan Details” for general guidance.)

Revised wall plan sheets must be transmitted quickly to avoid construction delays.

BUREAU OF LOCAL PROJECTSThe Bureau of Local Projects (Local Projects) will follow the policies listed above on local entity projects which affect the State System. Generally, Geotechnical Services is not involved with Local Projects walls. However, there may be special cases where Local Projects requests the expertise of Geotechnical Services.

ATTACHMENTSIndex

Attachment #1Wall Serial Number Request

Attachment #2 Wall Field Check Template

Attachment #3 Wall Stationing Guidelines

Attachment #4 Distribution of Shop Plans

Attachment #5 Wall Structure Type Abbreviations



Title Sheet



Retaining Wall & Noise Wall Layout



Summary of Retaining Wall and Index of Drawings



Summary of Retaining Wall and Quantities



Retaining Wall General Notes



Summary of Design Soil Parameters



Common Retaining Wall Details



Legend - Retaining Walls



Retaining Wall Plan & Elevation



Retaining Wall Typical Section Details



Miscellaneous Details



Plan and Elevation



Noise Wall/Retaining Wall Section



Noise Wall General Notes and Index of Drawings



Noise Wall Quantities & Foundation Summary



Noise Wall Drilled Shaft Data



Nose Wall



Miscellaneous Noise Wall Structural Details



Noise Wall Drilled Shaft Details



Noise Wall Plan and Profile



Road Cross Sections



Attachment #1



Attachment #2

FIELD CHECK TEMPLATE FORM

Attachment #N for Field Check of Project No. RR-CCC KA-PPPP-01 Let Date: MM/YY

Wall Number: RRR-CCC-MM.MM(WWWW) RM MMM.MM Stationing Baseline (Mainline, ramp)

1 Reference: Station Offset 2 Secondary Description: Route Station Offset 3 Secondary Function (Over, under, frontage road) 4 Wall Type 5 Wall Purpose 6 Minimum Height Maximum Height

Total Length of Wall along Centerline of Wall 883 Est. Cost of Work Field Check Est. Cost

7 Associated Structures (Bridge)(Wall) 8 Identifying Information for Associated Structures RR-CCC-MM.MM (WWWW/BBB) Utility Concerns Hydraulics, Drainage and Permitting Concerns Type of Work (New, replacement, existing) Plan Sheet Revision Responsibility

Attachment #N+1 for Field Check of Project No. RR-CCC KA-PPPP-01 Let Date: MM/YY

Wall Number: RRR-CCC-MM.MM(WWWW) RM MMM.MM Stationing Baseline (Mainline, ramp)

1 Reference: Station Offset 2 Secondary Description – Route Station, Offset 3 Secondary Function (Over, under, frontage road) 4 Wall Type 5 Wall Purpose 6 Minimum Height Maximum Height

Total Length of Wall along Centerline of Wall 883 Est. Cost of Work Field Check Est. Cost

7 Associated Structures (Bridge)(Wall) 8 Identifying Information for Associated Structures RR-CCC-MM.MM (WWWW/BBB) Utility Concerns Hydraulics, Drainage and Permitting Concerns Type of Work (New, replacement, existing) Plan Sheet Revision Responsibility

1. See Attachment #2, Wall Layout Guide 2 Defines the wall with respect to a second baseline. This is for location purposes if helpful. 3. Defines the second baseline. (Route over, under, etc.) 4. Describe and use CANSYS codes: Example - MSE Panel Wall (YMLX) - From Kansas Structure Coding Guide5. Earth retaining, noise abatement, hydraulic, aesthetic treatment, etc. 6. Wall heights are measured from top of the footing to the top of the wall cap. 7. Associated structures are structures that are within 1.5 x height of the wall (any direction) 8. Route, county, reference mile, wall number.



Attachment #3

SBO form 07-31-2007 SBO - 3 Figure 1



Attachment #4

Approved Shop Detail Distribution List

FabricatorContractor (General and Sub-Contractor)

District Engineer w/aArea Engineer w/aArea Construction Engineer w/aMetro Engineer and/or FEA if applicable w/a

Operations Engineer, Bureau of Construction and Materials w/aAsst. Chief, Bureau of Construction and Materials

Bureau of Road DesignPavement Section Consultant (if applicable) w/a

State Geotechnical Engineer w/aManagement System Analyst, Bridge Section w/a

Bridge County Files ==> Records and Workflow ManagementProjectwise

Notes:

• Shop drawing format and distribution shall conform to Section 105.10b of the KDOT Stan-dard Specifications for Road and Bridge Construction



Attachment #5

DATABASE CHARACTER WALL TYPE CODES

CANSYS / PONTIS / BROMS alpha character fields

Material Type Superstructure/Structure Type Design Type

A = Aluminum AT = Soil Nail/Tie-Back A = Aesthetic (Wall)B = Stone BN = Bin X = Retaining (Wall)C = Corrugated Metal CT = Cantilever Y = Hydraulic (Wall) D = Geotextile Fabric ER = Earth Z = Noise (Wall)E = Earth (soil) GB = GabionF = Composite (Fiberglass, PVC, etc.) GV = GravityG = Galvanized Steel MB = Mechanically Stabilized Earth, BlockH = ML = Mechanically Stabilized Earth, Panel I = Wrought Iron PF = Panel Frame J = SD = Soldier Pile K = SH = Sheet Pile L = Lightweight Concrete SV = Semi-Gravity M = Stone MasonryN = None (for BROMS temporary use)O = P = Prestressed ConcreteQ = R = Reinforced ConcreteS = SteelT = TimberU = Unknown (for BROMS temporary use)V = W = Weathering SteelX = Post-Tension ConcreteY = Precast ConcreteZ =



Appendix A Structure Protection GuidelinesUse of this guideline

This guideline is intended to be followed with minimal deviation when designing projects with new grade separation span bridges where the piers are located within the clear zone. For rehabili-tation projects on existing bridges or to the roadway passing below, when the pier is located within the clear zone, the bridge and road engineer will determine, together, the overall risk to the existing structure. The road engineer will determine the clear zone requirements, the risk of impacting the structure, guard rail need, potential traffic impedance, mowing restriction, drainage and site conditions. The bridge engineer will determine the effects of the impact on the structure and the risk of potential loss in service. Both the Road Section and the Bridge Section will deter-mine how best to adhere to the guidelines.

AASHTO does not differentiate between new and existing structures when referring to the analy-sis of vehicular or railroad collisions. The intent is to provide a specification for the design of new structures. Bridge rehabilitation, repairs and maintenance are typically governed by specifi-cation written at the time the structure was built. Improvements to the AASHTO Bridge Design Specifications are incorporated into bridge rehabilitation work when the work can economically enhance material performances, structural durability, public safety, or improve life-cycle costs. The designer will determine if the increased investment cost is reasonable for the risk being taken.

For new structures, the flow charts follow current AASHTO Specifications. By incorporating these design requirements into the development of the project scope, such items as highway geo-metrics, span layout, superstructure and substructure types, and locations are all considered as variables. For existing structures, project variations are not always possible and therefore, a weight must be placed on balancing cost verses risk within the project scope.

It is not the intent of this guideline to consider structure protection when the project scope is lim-ited to only maintenance of either the existing bridge or existing roadway passing below. Nor is the intent of this guideline to search out structures falling within this area of concern and which are not meeting current requirements, as a sole reason for retro-fitting the structure unless specifi-cally directed to do so.

Interpretation of Current Specifications

For vehicular impact, the current AASHTO Specifications use a distance of 30 ft. and the term “clear zone” interchangeably when defining the limits required for protection of the structure. KDOT has determined that “clear zone”, as defined by the Road Section, will be the controlling distance. Article 3.6.5 describes a 600 kip load acting at an angle not greater than 15 degrees from the edge of the pavement and located 5 ft. above the ground. This vehicular collision force (CT) will be used unless protected, per Article 3.6.5.1, or if the structure is exempt per Article C3.6.5.1. The determination of exemption is based on the structure function being classified as critical or typical, and will follow an evaluation of risk. Considerations will also include route redundancy, length of detour, multi-layer interchange, and other local considerations. Consult the Bridge Sec-tion and District for guidance.

Volume III US (LRFD) Bridge Section Version 10/13 3 -11 - 1


New Structures

Use one of the following AASHTO Specifications taken from Article 3.6.5.1 to protect the pier if the pier is within the clear zone.

• Design the pier to withstand impact.• Use an embankment to protect the pier from vehicular impact.• When the distance from the back of the barrier to the pier is less than or equal to 10’-0”, use a

54” barrier designed for a TL-5 loading condition.• When the distance from the back of the barrier to the pier is greater than 10’-0”, use a 42”

barrier designed for a TL-5 loading condition.

Note: KDOT has not crash tested a 42” or 54” barrier for TL-5 loading but, has detailed the rein-forcement based on, Development of 42 and 51” TALL SINGLE –FACE, F-SHAPE CON-CRETE BARRIERS (Faller, R. 2002) defining that reinforcement.

Existing Structures

Use this guide along with the risk of a specific structure as a method of determining the level of protection required. Evaluate the capacity of the column and the connections to the foundation and pier beam elements to determine the resistance. Factors which affect this resistance include, but are not limited to:

• The continuity of the superstructure and the ability for full or partial stress reversal and redis-tribution of force effects.

• The continuity of the superstructure to the substructure and any frame action which might aid in the distribution of force effects.

• The condition of the bearing devices and ability to resist translations and rotations.• The degree of redundancy of the substructure.• The continuity of the substructure to the foundation system. • The amount of confinement reinforcement within the column and potential ultimate reserve

capacity beyond the design capacity. Refer to Section 3.5.1.6.3.• The cost compared to the risk.

Allowable Damage

The intent of this protection is so that upon impact the structure is prevented from collapsing. A repair may require closing or partial closing of the structure or the roadway passing below. The level of allowable damage and the extent which the structure is out of service must be measured compared to the cost of the protection. In congested urban areas where loss of service may not be acceptable, the level of protection should be increased.



Matrix and Summary of Structure Protection



Median Protection



Bridge Rail (Barrier)



Bridge Rail (Corral)



MSE and Pier Protection



Pier and Median Protection



MSE Captured Coping Details



MSE Barrier and Coping Details for Modular Block



MSE Barrier and Coping Details for Panel Wall



Appendix B EXAMPLE CALCULATIONSThe force on a column due to a thermal change in length of the superstructure is:

a) One end free, one end fixed:

& M = Ph

b) Both ends fixed:

& M = Ph/2

where: E = Modulus of Elasticity of column, ksi(For concrete bridge use E = 1,000 ksi)

I = Moment of Inertia of column, in.4

a = Coefficient of Thermal Expansion of superstructure= 6.5 x 10-6/F (Steel)= 6.0 x 10-6/F (Cast-in-Place & Prestressed Concrete)

T = Temperature change of superstructure, FL = Expansion length of superstructure, Feeth = Column height, FeetP = Force per column, Kips

See the next page for a method of determining distribution of longitudinal temperature forces to columns.

Distribution of Longitudinal Temperature Forces (Symmetrical Bridge)If the superstructure is supported by elastomeric bearing pads, the thermal force on the columns must take into account the deflection of the column and the deflection of the pad.

If the bridge is symmetrical, the point of zero thermal movement is known and the following procedure may be used to compute forces.

P 3 EI a T L

(144) h3-------------------------=

P 12 EI a T L

(144) h3---------------------------------=



Elevation of Steel Girder Bridge

Thermal Coefficient: Steel = 6.5 x 10-6

Design Temperature Range: Steel = 90F

(See Loads on Piers, (e) Temperature)

Total Deflection at Abut. #1 & Pier #1

T1 = (85’ + 65’) 90F x 6.5 x 10-6 x 12 in/ft. = 1.05"T2 = (85’) 90F x 6.5 x 10-6 x 12 in/ft. = 0.60"

Deflection at Piers:

Pier = Pad + Col

a) Elastomeric Pad deflections are calculated as follows:

Pad = Deflection (in.) P = Force (lbs.) L = Length Pad (in.)

W = Width Pad (in.)T = Total thickness of

Elastomer Layers (in.)G = Shear Modulus (psi.)N = Number of pads

Pad P T L W G N ---------------------------------=



The Shear Modulus (G) varies with durometer, temperature and time. Use 60 durometer pads with a G(max) = 300 psi. for temperature fall and G(min) = 150 psi for temperature rise. Run two sets of calculations.

b) Column deflections are calculated as follows:

Col = Deflection (in.)P = Force (lbs.)h = Height (in.)*I = Gross Inertia (in.4)E = Modulus of Elasticity (psi.)

* For skewed, free-standing piers, increase moment of inertia by the procedure shown following these examples.

At Abut. #1 = Abut. #2

(P1)

T1 = Col

1.05" = 5.54x10-5 (P1)

P1 = 18,952 lbs./Abut.

At Pier #1 = Pier #3

(P2)

(P2)

Pad + Col = 2.26x10-5 (P2)

T2 = Pad + Col0.60" = 2.26x10-5 (P2)

P2 = 26,549 lbs/Pier

Col P h 3

3 E I -------------------=

Col P1 10x12 in/ft. 3

3 29x106 5x71.7 in.4 ----------------------------------------------------------- 5.54x10-5==

Pad P2 2 18 12 300 6 pads ----------------------------------------------------- 0.51x10-5==

Col P2 30 12 in/ft. 3

3 3.6 106 3 82 448 --------------------------------------------------------------- 1.75x10-5==



Distribution of Longitudinal Temperature Forces (Unsymmetrical Bridge)If the bridge is unsymmetrical and/or with different column lengths, the point of zero thermal movement is unknown and must be solved for:

Elevation of Steel Girder Bridge

Note: Use the same coefficients, temperature ranges and bearing pads as in previous example.

Total Deflection of Bents

T1 = (60 + 85 + X) 90F x 12 in/ft. x 6.5 x 10-6 = 118+ 0.00702 (X) in.

T2 = (85 + X) 90 F x 12 in/ft. x 6.5 x 10-6 = 0.597+ 0.00702 (X) in.

T3 = (X) 90F x 12 in/ft. x 6.5 x 10-6 = + 0.00702 (X) in.

T4 = (85 - X) 90F x 12 in/ft. x 6.5 x 10-6 = 0.597 - 0.00702 (X) in.

T5 = (85 + 30 - X) 90 F x 12 in/ft. x 6.5 x 10-6 = 0.807- 0.00702 (X) in.

P1 + P2 + P3 = P4 + P5

@ Abut. #1:

(P1)

Col P H 3

3 E I ------------------- P1 10 12 in/ft. 3

3 29 106 5 71.7 in4 ---------------------------------------------------------------==

5.54 10-5=

T1=



@ Pier #1:

(P2)

(P2)

T2 = Pad + Col (P2)

@ Pier #2:

(P3)

@ Pier #3:

(P4)

(P4)

T4 = Pad + Col (P4)

@ Abut. #2:

(P5)

Solve for P:

@ Abut. #1:

@ Pier #1:

@Pier #2:

Pad PTLWGN------------------- P2 2

18 12 300 6 --------------------------------------- 0.514 10-5===

Col P2 25 12 3

3 3.6 106 3 82 448 --------------------------------------------------------------- 1.011x10 5– ==

T2 1.525 10-5=

Col P3 30 12 3

3.6 106 247 344 ------------------------------------------------ 1.747 10-5 ==

= T3

Pad P4 2 18 12 300 6 --------------------------------------- 0.514 10-5==

Col P4 18 12 3

3.6 106 247 344 ------------------------------------------------------ 0.377x10 5–==

T4 0.891 10-5=

Col P5 10 12 3

29 106 5 71.7 --------------------------------------------------- 5.540 10-5 ==

= T5

P1 T15.54 10-5-------------------------- 1.018 0.00702 X +

5.54 10-5------------------------------------------------==

P2 T21.525 10-5----------------------------- 0.597 0.00702 X +

1.525 10-5------------------------------------------------==

P3 T31.747 10-5----------------------------- 0.00702+ X

1.747 10-5------------------------------------==



@Pier #3:

@Abut. #2:

Since P1 + P2 + P3 = P4 + P5, the above equations can be solved for “X”:

-18,375.5 126.7 X-39,147.5 460.3 X

0.0 401.8 X+67,003.4 787.9 X+14,566.8 126.7 X+24,047.2 1,903.4 X X = 12.6 ft.

Therefore,

P1 = 18,375.5 + 126.7(12.6) = 19,972 lbs.P2 = 39,147.5 + 460.3(12.6) = 44,947 lbs.P3 = + 401.8(12.6) = 5,063 lbs.P4 = 67,003.4 - 787.9(12.6) = 57,076 lbs.P5 = 14,566.8 - 126.7(12.6) = 12,970 lbs.

The controlling column temperature force is located at Pier #3 (P4). If it is determined this force is too large, the designer could select one of the following options: (a) Increase the height of the pad to make it more flexible. (b) Specify an isolation bearing design to redistribute the forces. (c) Equip the elastomeric pad with a teflon sliding surface.

Moment of Inertia Adjustment for Free-Standing Skewed Piers

A skewed, free-standing column bent pier will inherently be stiffer in the longitudinal direction then a non-skewed pier. This increase in stiffness due to the skew will produce larger moments in

P4 T40.891 10-5----------------------------- 0.597- 0.00702 X

0.891 10-5-----------------------------------------------==

P5 T55.540 10-5----------------------------- 0.807- 0.00702 X

5.540 10-5-----------------------------------------------==



the columns. To compute the resultant Moment of Inertia for the Pier (Ir), the following procedure may be used:

For two, three, four and five column piers of equal height and size of column;

Izz = (4) Iyy (see derivation below)

Iyy = Io (N) N = Number of columnsIo = Moment of Inertia of one column

Skew Iyy Izz Ir

0 1 4 1010 1 4 1920 1 4 1.3530 1 4 1.7540 1 4 2.2450 1 4 2.76 90 1 4 4.00

Adjustment of moments of inertia should be used for skews greater than 20 degrees.



Derivation:

Stiffness is inversely proportional to deflection, therefore;

Reference:Missouri Highway and Transportation Department Bridge Manual.



Appendix C Sheet Pile Retaining Wall Example MathCadd

Boussinesq Equation (Modifed) For Point Load

Heigth of the Wall.......... H 10��

Depth Below th Wall.......... Z 0 H��

X1 3�� X2 9��Distance(s) from Wall Face................

Qp 16000��Point Load .......................

Dimensionless Parameters...... n Z( )ZH

�� m1X1

H�� m2

X2

H��

F1 Z( )1.77 m1

2� n Z( )2

�

m12 n Z( )2�

��

3�� F2 Z( )

1.77 m22

� n Z( )2�

m22 n Z( )2�

��

3��Modified Boussinesq Equation

Increase in Pressure as a function of Depth... Δp1 Z( )Qp

H2

��

F1 Z( )�� Δp2 Z( )Qp

H2

��

F2 Z( )��

The increase in pressure as a function of Depth for two point loads

0 100 200 300 400 50010�

8�

6�

4�

2�

0

Z

Δp1 Z( )0 20 40 60

10�

8�

6�

4�

2�

0

Z

Δp2 Z( )

Z

0-1

-2

-3

-4

-5

-6

-7

-8

-9

-10

� Δp1 Z( )

0254.88

464.051

393.333

260.997

162.121

100.693

64.01

41.932

28.32

19.681

� Z

0-1

-2

-3

-4

-5

-6

-7

-8

-9

-10

� Δp2 Z( )

04.16

14.941

28.32

40.215

48.15

51.561

51.162

48.156

43.704

38.685

�

Resultant of the Pressure Diagram

Ph10.78 m1 0.4�� 1.5��

HQp

��

�� Ph1 1.488 103�� Ph2

0.78 m2 0.4�� 1.5��

HQp

��

�� Ph2 48�

R1 0.59 m1 0.4�� 0.55�� H�� R1 6.45� R2 0.59 m2 0.4�� 0.55�� H�� R2 3.15�

Is the Live Load Supported by the Sheet Pile (1=yes & 0=no) ......................................... LL 1��

Ph1 Ph1 LL 0�if

0 otherwise

�� Ph2 Ph2 LL 0�if

0 otherwise

��

Sheet pile wall in sand with live load and water and bracing (ver 1.0).MCD 1



Solution taken from Braja M. Das," Principles of Foundation Engineering" pp. 334-340

Soil Parameters

Internal Friction angle..................... ϕ 32��

Soil Unit Weight (dry)..................... γ 110��

Unit Weight of Water..................... γw 62.4��

Soil Unit Weight (sat.)................... γsat 125��

Effective Unit Weight..................... γ' γsat γw��

Wall Parameters

Water table to top of Wall.............. L1 10��

Dredge Line to water Table............. L2 0��

L L1 L2�� L 10�Step 1

Ka tan deg 45ϕ

2�

��

��

��

2��

Kp tan deg 45ϕ

2�

��

��

��

2��

Slope: m γ' Kp Ka�( )��Step 2

p1 γ L1� Ka��

p2 γ L1� γ' L2�� Ka��

Step 3

L3p2

γ' Kp Ka�( )�� L3 1.832�

Step 4

P12

p1� L1� p1 L2��12

p2 p1�� L2��12

p2� L3��

��

Ph1� Ph2�� P 3.535 103��

Step 5 Summing Moment about E

z'1P

p1 L3 L2�L1

3�

��

� p1 L2� L3L2

2�

��

��12

p2 p1�� L2� L3L2

3�

��

��12

p2� L3� L3L1

3�

��

��

Ph1 R1 L3�� Ph2 R2 L3��

��

��

�� z' 4.582�




Step 6

p5 γ L1� γ' L2�� Kp� γ' L3� Kp Ka�( )�� p5 3.918 103��

Step 7

A'4P 6 z'� p5� 4 P��

γ'2 Kp Ka�( )2�

��A'1p5

γ' Kp Ka�( )�� A'2

8 P�γ' Kp Ka�( )�

�� A'36 P� 2 z'� γ'� Kp Ka�( )� p5��

γ'2 Kp Ka�( )2�

��

A'1 21.236� A'2 153.298� A'3 3.495 103�� A'4 1.266 104

��

Step 8

Guess: L4 15��

Given

L44 A'1 L4

3�� A'2 L4

2�� A'3 L4�� A'4� 0=

L4 Find L4� �� L4 13.664�

Step 9

p4 p5 γ' L4� Kp Ka�( )�� p4 6.439 103��

Step 10

p3 γ' Kp Ka�( )� L4�� p3 2.521 103��

Step 11

L5p3 L4� 2 P��

p3 p4�� L5 3.055�

The Theoretical Depth of Penetraion is

Dt L3 L4�� Dt 15.496�

The Actual Depth is 1.3 x Theoretical Depth

Da Dt 1.3�� Da 20.145�

Sizing the Sheet Piling

Z'2 P�

γ' Kp Ka�( )�� Z' 6.191�

Max. Moment

Mmax P z' Z'�( )�12γ'� Z'2� Kp Ka�( )��

��

Z'3

��

�� Mmax 3.079 104�� ft*lb/ln ft of wall

Required Section Modulus

Allowable Stress in the Pile............................ σall 15000�� psi




S

Mmax 12�

σall�� S 24.632� in3/ln ft of wall <========

n 1 7��

f

0

p1

p2

0

p2 Dt L5�� m��

p4

0

L

L2

0

L3�

Dt� L5�

Dt�

Dt�

��

��

�� xf 1� �

1000��

y f 2� ��

2� 0 2 4 6 8

20�

10�

10

Dep

th,(f

t)

yn




Pressure

Pressure,

xn

Bracing Calculations

The following solutions are based on the the following assumptions:(1) The active earth load is supported by the sheet.

(2) The live load is supported by the H-pile Bracing.

(3) The uniform distributed load = tributary area.

(4) Walers are simply supported at the ends

(5) Length to fixity is 7'-0" below dredge line.

Bracing Parameters

Distance from top of wall to 1st whaler........ d1 5��

Distance from 1st to 2nd whaler................. d2 5��

Distance from 2nd to 3rd whaler................. d3 2��

Distance between vetical supports............ Lhp 10��

Section of Whalers.................... Sw 43��

Section of Vertical .................... Sv 66.8��

L 10�

Area behide the Live Load PressureDiagram

t1 d1d22

� d2 0�if

L otherwise

�� t2d22

d32

� d3 0�if

L t1�( ) otherwise

�� t3d32

L� d1 d2� d3�( )� d3 0�if

0 otherwise

��

Uniform distrubuted loads to Whaler

w1t1�

0ZΔp1 Z( )

��

dt1�

0ZΔp2 Z( )

��

d�� w1 1.938 103��

w2t1� t2�

t1�ZΔp1 Z( )

��

dt1� t2�

t1�ZΔp2 Z( )

��

d�� w2 246.153�

w3t1� t2� t3�

t1� t2�ZΔp1 Z( )

��

dt1� t2� t3�

t1� t2�ZΔp2 Z( )

��

d�� w3 52.829��




w2 w2 d2 0�if

0 otherwise

�� w3 w3 d2 0�if

0 otherwise

��

Stresses on Whalers due to Live Load

Mw1w1 Lhp

2�

8�� Mw2

w2 Lhp2

�

8�� Mw3

w3 Lhp2

�

8��

σw1Mw1 12�

Sw 1000�� σw2

Mw2 12�

Sw 1000�� σw3

Mw3 12�

Sw 1000��

σw1 6.759� ksi σw2 0.859� ksi σw3 0.184�� ksi

Stresses on Vertical due to Live Load

Mvw1 Lhp�

2L 7�( ) d1�[ ]�

w2 Lhp�

2L 7�( ) d1� d2�[ ]��

w3 Lhp�

2L 7�( ) d1� d2� d3�[ ]��

σvMv 12�

Sv 1000�� σv 22.194� ksi




Appendix D Noise Abatement Policy

KANSAS DEPARTMENT OF TRANSPORTATION

Policy Statement on Highway

Noise Abatement

EffectiveAugust 28, 1996

PREFACE

Traffic noise impacts vary with highway location relative to human activities and traffic characteristics. The Kansas Department of Transportation (KDOT) evaluates traffic noise in accordance with federal regulations and, as impacts become more severe, noise mitigation measures are investigated. In order to address these issues in a consistent and objective manner, the following policy and procedure statements are provided.

Authority

The Federal Highway Administration's Procedures for Abatement of Highway Traffic Noise and Construction Noise is found in 23 CFR 772. The KDOT noise policy is based upon this FHWA regulation, and is deemed to be consistent with it.

1) Traffic Noise Reduction Responsibility

Traffic noise impacts develop in different ways. When new roadways are constructed through established neighborhoods, impacts are recognized immediately after the new facility is opened to traffic. However, when new construction takes place in rural or undeveloped areas, impacts develop as residents and businesses are constructed along the new roadway.

In view of these circumstances, KDOT endorses a "systems" approach to traffic noise reduction that is sanctioned by the Federal Highway Administration (FHWA) and the American Association of State Highway and Transportation Officials (AASHTO). The systems approach is a program of shared responsibility whereby the control of undesirable effects of traffic generated noise requires a three-part approach as follows: (1) Reduction of noise at its source, ie. the motor vehicle; (2) proper land uses and developments with appropriate building standards adjacent to high traffic volume roadways; and (3) diminishing traffic noise that reaches noise-sensitive areas by incorporating noise reduction measures into highway design. The first component relies on private industry; the second, on local governments; and the third, on Federal and state agencies responsible for highway location and design. To use only one method to address traffic noise might be prohibitive

Policy Statement on Highway Noise Abatement



2

Kansas Department of Transportation

in cost, but through a joint effort of those involved, an appropriate balance of cost and responsibility can be achieved. Policy and procedure stated in this document reflects this systems approach to traffic noise reduction.

2) Noise Prediction

All predictions of noise levels on KDOT highway projects will be made using a noise prediction model approved by the FHWA. In predicting noise levels and assessing noise impacts, the posted speed limit at the time of the existing traffic noise study will be used.

3) Noise Levels

a. Descriptor

Noise studies for KDOT projects will use Leq, the equivalent sound level.

b. Existing Levels

Leq values existing in a project corridor before construction will normally be determined through field measurements. However, in certain cases, these values can be obtained through execution of the Model.

c. Future Levels: Without Barrier

Post-construction Leq values that approach or exceed the FHWA Noise Abatement Criteria (NAC) found in 23 CFR 772 are deemed to be sufficiently high to warrant abatement analysis. Noise abatement measures including traffic management measures, alignment shifts, buffer zones and noise barriers will be evaluated. The following table defines approach for each of the Land Use Categories.

Land Use Noise Abatement Approach Category Criteria LeqdV) defined as

A 57 dBA 56 dBA

B 67 dBA 66 dBA

C 72 dBA 71 dBAIn addition, impacts are deemed to occur when future predicted no barrier levels




3


substantially exceed existing levels. KDOT has an agreement with FHWA that defines impacts. These definitions are:

0-5 dBA increase - No impact6-10 dBA increase - Minor impact11-15 dBA increase - Moderate impact> 15 dBA increase - Severe impact

Abatement analysis, as outlined in 23 CFR 772, will be conducted when impacts are classified as moderate or severe.

4) Barriers

a. Barrier Projects

KDOT will only construct noise barriers as part of highway construction or re-construction projects. KDOT will not participate in the Type II program of retrofitting existing highways with noise barriers until Federal standards are established exclusively for Type II and other enhancement projects (See 23 CFR 772.5(i) and 772.7 (b)).

b. Insertion Loss

Insertion loss is the difference in Leq with and without the barrier (barrier minus no barrier level). The insertion loss goal for each impacted sensitive receptor is 5 dBA or more.

c. Location

In at-grade or fill situations, barriers should be built as close to the highway as possible. If necessary, barriers can be located on top of jersey-type barriers, and placed at the edge of shoulder, ( approximately 10-12 feet from traffic). If jersey-type barriers or methods of crash protection are not used, noise barriers should be outside the 30 foot clear zone.

When barriers are constructed at or near the shoulder line, consideration must be given to safety, drainage, and ice and snow removal.

In cut situations, barriers should be placed as close to the right-of-way line as possible. This will maximize noise reduction effects of the barrier. In all cases barriers should be constructed on KDOT right-of-way.

Policy Siuiemem on Highway Noise Abatement



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d. Height

For aesthetic and cost reasons, barriers should be tall enough to provide adequate noise reduction, and no taller. For KDOT projects, the maximum height of any barrier above the ground line will be 16 feet. Barriers taller than 16 feet would probably result in negative visual impacts on the surrounding properties.

Also for aesthetic reasons, barrier height should be limited as follows: The distance from the barrier to any inhabited buildings should be at least four times the barrier height. For example, if the distance from the barrier to a row of protected houses is 44 feet, the maximum height of the barrier should be 11 feet.

e. Length

Barriers shall be designed with the shortest length possible. Typically, barriers will need to extend beyond the last receiver by a distance four times the distance from the receiver to the barrier.

f. End Treatment

Abrupt endings of barriers should be avoided. Barrier heights should be tapered to the ground and vegetation may be used to soften the end appearance.

g. Access

Working space behind the barrier with provisions for access should be provided, or maintenance agreements with other public bodies or private individuals should be made.

h. Materials

The principal issues involved in material selection are aesthetics, community desires, constructability, and maintenance. Normally, concrete and masonry based materials are the most suitable in addressing these issues. Wood barriers are a less expensive alternative, but must be carefully designed and monitored in terms of treatment and water content in order to minimize maintenance problems. Metal barriers are easily damaged, and are often not received positively regarding aesthetics. Vegetative screens do not produce meaningful noise reduction, due to a lack of material density.




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i. Cost

Because a small number of people benefit from a relative large expenditure of funds, barriers, if constructed, must be determined to be reasonable, feasible, and cost effective. For KDOT projects cost effectiveness is defined as barrier cost per receiver at or below the national average guideline for barrier cost effectiveness. This guideline was determined to be $25,000 in 1995 dollars, based upon studies performed for KDOT.

When determining cost effectiveness of a potential barrier, each sensitive receptor receiving 5 or more dBA insertion loss is counted as one receiver, and each receiving 3-4 dBA insertion loss is counted as one half receiver.

The cost data in Table 1 should be used when computing the barrier cost per receiver. These data have been incorporated into the NOISE software library. It is the intent of KDOT to update the values in Table 1, as well as the $25,000 barrier cost per receiver national criterion, as needed.

It should be noted that the data in Table I are to be used in conjunction with the guideline for cost effectiveness. THEY ARE FOR COMPARISON PURPOSES ONLY. Actual barrier costs will vary.

It should also be noted that the comparison of proposed barrier costs using the guideline is to assist KDOT in making decisions about barrier feasibility. Any final decision on barrier construction will be based on a variety of factors.

Barrier HeightRange in feet

Cost per linear foot in 1995 dollars

Berm Concrete Wood Metal

01-05 48.66 105.79 18.77 28.0905-10 79.11 193.33 94.21 136.7910-15 1-17.18 302.74 220.91 272.6615-20 155.28 412.13 347.61 408.5320-25 193.34 521.55 474.30 544.39

TABLE 1 - OPTIMA Cost Data for Kansas in 1995 Dollars




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j. Maintenance

The goal for all barriers constructed by KDOT is minimum maintenance cost. Each barrier design should be performed with this goal in mind.

k. Aesthetics

Successful barrier projects not only adequately reduce noise levels, but also receive positive response regarding appearance (aesthetics). In order to assure this positive response, care should be taken in selecting a color scheme and surface texture, and use of landscaping should be considered in design.

1. Documented Community Support

No barrier will be constructed by KDOT unless there is: a) formal endorsement by appropriate local officials, and; b) documented support of at least 80 percent of the residents of all first and second row sensitive receptors.

m. Isolated Receivers

Barriers will not be constructed for individual residences or other isolated receivers.

5) Decision to Build or Not Build a Barrier

The decision on whether to build or not build a barrier is always a KDOT decision. Factors that influence that decision include:

1. Documented impacts (Section 3.c.) 2. Insertion loss of 5 dBA reasonably attainable (Section 4.b.) 3. Documented official community support (Section 4.1.) 4. Documented support of affected residents (Section 4.1.) 5. Cost effectiveness of barrier attainable (Section 4.i.) 6. Assurance of positive aesthetic impacts (Sections 4.f., k.) 7. Minimized impacts on maintenance operations (Section 4.j.)

In addition to these 7 factors, the following must also be considered:

1. Other Noise Sources - If significant non-highway noise sources exist in the project area, such as major rail lines or airports, noise barrier effectiveness will likely be compromised. Barriers will not be built when such a compromise is evident.




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2. Chronology of Development - It is KDOT policy to fully inform local officials about noise levels resulting from its projects. In spite of this policy, there is too often still noise sensitive development that occurs in the proximity of these projects. KDOT does not want noise sensitive development to occur immediately adjacent to high volume, high noise level highways. KDOT will not participate in the evaluation or construction of traffic noise barriers for a project, where development was not planned, designed, and programmed prior to the Point of Public Knowledge. The Point of Public Knowledge shall be defined as the date an approved Categorical Exclusion is issued, or the date of an approved Record of Decision or Finding of No Significant Impact.

3. Local Participation - If a local jurisdiction wishes a noise barrier that is deemed not reasonable by KDOT, the barrier may be installed, provided the locality participates in the cost, including but not limited to preliminary engineering, construction, safety, and maintenance, and that KDOT's material, design, and construction specifications are used.

Any barrier that is marginally cost effective may still be constructed provided the locality is willing to share in the funding through an appropriate partnership with KDOT.

6) Sensitive Receptors

Although all activities that have a NAC are reviewed, single family residences have the highest priority for limited highway construction funds.

Approved:E. Dean Carlson,-SecretaryKansas Department of Transportation




Appendix E Landscape Retaining Wall Policy Revision 1

Kansas Department of Transportation MEMO TO: Rick E. Kreider, P.E., Chief Bureau of Materials and Research FROM: James J. Brennan, P.E. Assistant Geotechnical Engineer DATE: December 30, 2008 Original Policy Dated February 24, 2004 SUBJECT: Landscape Retaining Wall Policy Revision 1 The Approved Proprietary Retaining Wall System list developed by our Agency has performed well for many years. However; the premise of all our design standards requires us to design to AASHTO minimum specifications. The conservative nature of the AASHTO criteria has actually hindered development of the MBW (Modular Block Wall) usage in low impact settings. An example would be to build a two foot exposed height retaining wall (3 blocks) while embedding the system 3 feet (4 blocks) and using reinforcement 8 feet in length. Although these design standards are widely considered too conservative, no significant effort has been made yet to address these deficiencies in AASHTO. Until these discrepancies are addressed by AASHTO, we recommend a policy (henceforth known as the Landscape Retaining Walls Policy or LRW Policy), whereby the less restrictive National Concrete Masonry Association Design Standards for Segmental Retaining Walls can be utilized for MBW systems on urban and secondary routes providing the following criteria are met: The total height of the retaining wall must be less than 6 feet. The live load surcharge cannot exceed 100 psf. The system cannot be defined as a critical structure whose failure would cause loss of life, serious loss of function or access to adjacent necessary services/structures, or result in significant property damage. Multiple tiered walls will not be considered landscaping walls even if the individual height of the component retaining walls is less than 6 feet. This policy will allow the use of a granular leveling pad. (rev. 12.30.08) Please contact us at (785)296-3008 after your review and revisions of the proposed policy so that we can proceed with its further development. AJG:JJB:jjb C: Ken Hurst, P.E., State Bridge Operations Engineer Loren Risch, P.E., State Bridge Design Engineer Ron Seitz, P.E., Chief, Bureau of Local Projects Mike Popp, P.E., Operations Engineer Corky Armstrong, P.E., Roadway Design Engineering Manager Joshua Welge, P.E., Soils Engineer Luke Metheny, Engineering Associate III Blair Heptig, Foundations Specialist


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