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Geotechnical Engineering Report Amara Apartments at the Rim

Talavera Ridge and Old Camp Bullis Road

San Antonio, Texas

June 27, 2016

Terracon Project No. 90165068

Prepared for:

Oden | Hughes

Austin, Texas

Prepared by:

Terracon Consultants, Inc.

San Antonio, Texas

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TABLE OF CONTENTS

Page

EXECUTIVE SUMMARY ............................................................................................................. i

1.0 INTRODUCTION ............................................................................................................. 1

2.0 PROJECT INFORMATION ............................................................................................. 1

2.1 Project Description ........................................................................................... 1

2.2 Site Location and Description .......................................................................... 2

3.0 SUBSURFACE CONDITIONS ........................................................................................ 2

3.1 Site Geology ...................................................................................................... 2

3.2 Typical Profile ................................................................................................... 3

3.3 Groundwater ..................................................................................................... 3

4.0 RECOMMENDATIONS FOR DESIGN AND CONSTRUCTION ...................................... 4

4.1 Geotechnical Considerations ........................................................................... 4

4.1.1 General .................................................................................................... 4

4.1.2 Expansive Soil Considerations ................................................................. 4

4.1.3 Existing Fill Considerations ...................................................................... 5

4.1.4 Borrow Pit area......................................................................................... 5

4.2 Earthwork .......................................................................................................... 6

4.2.1 Site Preparation ........................................................................................ 6

4.2.2 Building Pad Preparation .......................................................................... 6

4.2.3 Material Requirements ............................................................................. 8

4.2.4 Compaction Requirements ....................................................................... 8

4.2.5 Grading and Drainage .............................................................................. 9

4.2.6 Earthwork Construction Considerations .................................................. 10

4.3 Foundations .................................................................................................... 10

4.3.1 Slab-on-Grade Foundation Design Recommendations ............................ 10

4.3.2 Shallow Foundation Construction Considerations ................................... 12

4.3.3 Drilled Piers Foundation ......................................................................... 12

4.3.4 Drilled Pier Construction Considerations ................................................ 14

4.3.5 Foundation Construction Monitoring ....................................................... 16

4.4 Seismic Considerations ................................................................................. 16

4.5 Swimming Pool ............................................................................................... 17

4.6 Pavements ....................................................................................................... 17

4.6.1 Subgrade Preparation ............................................................................ 18

4.6.2 Design Considerations ........................................................................... 18

4.6.3 Pavement Section Materials ................................................................... 20

4.6.4 Pavement Joints and Reinforcement ...................................................... 21

5.0 GENERAL COMMENTS ............................................................................................... 23

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TABLE OF CONTENTS, CONTINUED

TABLE – LATERAL DESIGN PARAMETERS

APPENDIX A – FIELD EXPLORATION

Exhibit A-1 Site Location Map

Exhibit A-2 Boring and Test Pits Location Plan

Exhibit A-3 Field Exploration Description

Exhibit A-4 to A-23 Boring Logs

Exhibit A-24 to A-26 Test Pits Logs (reference Terracon Project No. 90155270)

APPENDIX B – LABORATORY TESTING

Exhibit B-1 Laboratory Testing

APPENDIX C – SUPPORTING DOCUMENTS

Exhibit C-1 General Notes

Exhibit C-2 Unified Soil Classification System

Geotechnical Engineering Report

Amara Apartments at the Rim ■ San Antonio, Texas

June 27, 2016 ■ Terracon Project No. 90165068

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EXECUTIVE SUMMARY

A geotechnical investigation has been performed for the proposed Amara Apartments at the Rim to

be constructed off of Talavera Ridge and Old Camp Bullis Road in San Antonio, Texas. Our

geotechnical engineering scope of work for this project included the advancement of 20 borings

at the project site to depths ranging from about 15 to 25 feet below the existing site grades.

Pertinent findings and recommendations generated from this study include those summarized

below:

The subsurface conditions at the boring locations are highly variable and consist of variable

fill materials with boulders and native Fat Clay, Lean Clay, Clayey Gravel underlain by highly

weathered Limestone.

Groundwater was not encountered in the borings during field activities.

The results of our laboratory tests indicate that the clayey soils encountered at the site are

low to highly plastic and will shrink and swell with changes in moisture content. The existing

Potential Vertical Rise (PVR) at the site is about 1 to 3 inches in its present condition and

depends on the encountered soil at each location. Detailed recommendations for building

pad preparation are included in the report. The recommendation should be reviewed and

possibly revised once the grading and finished floor elevations are available.

The proposed structures may be supported on a slab-on-grade foundation system provided

the building pads are prepared as recommended in this report. We understand the client has

selected a design PVR of 1½ inches.

Both flexible and rigid pavements may be considered for this project.

The International Building Code, Table 1613.3.2 IBC seismic site classification for this site

is C.

This summary should be used in conjunction with the entire report for design purposes. It should

be recognized that details were not included or fully developed in this section, and the report must

be read in its entirety for a comprehensive understanding of the items contained herein. The

section titled GENERAL COMMENTS should be read for an understanding of the report

limitations.

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GEOTECHNICAL ENGINEERING REPORT

AMARA APARTMENTS AT THE RIM

TALAVERA RIDGE AND OLD CAMP BULLIS ROAD

SAN ANTONIO, TEXAS

TERRACON PROJECT NO. 90165068 JUNE 27, 2016

1.0 INTRODUCTION

Terracon Consultants, Inc. (Terracon) is pleased to submit our Geotechnical Engineering Report

for the proposed Amara Apartments at the Rim off of Talavera Ridge and Old Camp Bullis Road

in San Antonio, Texas. The project was authorized by Mr. Tim Shaughnessy on April 7, 2016

through signature of Terracon Proposal No. P90165068R2 dated April 7, 2016. This project was

completed in general accordance with the referenced proposal. The project was delayed due to

significant rainfall and access difficulties.

The purposes of this report are to describe the subsurface conditions observed at the borings

drilled for this study, analyze and evaluate the test data, and provide recommendations with

respect to:

subsurface soil conditions groundwater conditions

earthwork

seismic considerations

foundation design and construction

floor slab design and construction

pavements swimming pool

Preliminary information and a reconnaissance study were previously conducted by drilling borings

and test pits, Terracon Project No. 90155270. The report was provided to the client via email

dated January 29, 2016. This report supersedes all preliminary recommendations.

2.0 PROJECT INFORMATION

2.1 Project Description

Item Description

Site layout See Appendix A, Exhibits A-1 and A-2: Site Location Plan and Boring

Location Plan, respectively.





Item Description

Structures

The project will include the construction of:

■ 8 four to five-story apartment buildings with club house and

swimming pool. Two of the buildings will be interconnected

with the club house.

■ Two parking decks.

Associated pavements consisting of parking lots and drive lanes

Building Construction

■ The buildings are anticipated to be wood-framed or steel

framed structure; supported on a shallow slab-on-grade

foundation system. We understand the design PVR is 1½

inches.

■ The proposed parking decks are anticipated to be supported

by either slab on grade or drilled piers foundation system.

Maximum loads Column loads were not available at the time of this report. We

anticipate that loads will be light for this type of construction.

Grading Grading plans were not provided at the time of this report.

Finished floor elevation At or near existing grades within ±2 feet (assumed).

Pavements New parking and drive lanes. Both asphalt and concrete pavements

will be considered.

Traffic loads

No specific traffic volumes have been provided. Therefore, Terracon

anticipates that traffic loads will be produced primarily by automobile

traffic and occasional trash removal trucks.

2.2 Site Location and Description

Item Description

Location This project site is located off of Talavera Ridge and Old Camp Bullis

Road in San Antonio, Texas.

Existing improvements Undeveloped land.

Current ground cover Grass, weeds, stock piles, rocks boulders and fill materials in the

upper 5 feet.

3.0 SUBSURFACE CONDITIONS

3.1 Site Geology

The San Antonio Sheet (1983) of the Geologic Atlas of Texas published by the Bureau of

Economic Geology of the University of Texas at Austin has mapped the Glen Rose Formation

(Kgru and Kgrl) of Lower Cretaceous Geologic Age at this site. The Glen Rose Formation is





further divided into the Upper Member, with the geologic symbol Kgru, and the Lower Member,

with the geologic symbol Kgrl. The Glen Rose Formation consists of limestone, dolomite, and

marl as alternating resistant and recessive beds which forms a “stairstep” topography. The

limestone is aphanitic (individual grains are too fine to see with the naked eye) to fine grained,

hard to soft and marly. The dolomite is fine-grained and porous.

3.2 Typical Profile

Site soils consist of uncontrolled fill and natural soil over weathered Limestone. The fill material

is highly variable, including fat clay, lean clay and clayey gravel. The native soil is also variable

and consists of similar materials. Limestone was generally encountered below about 6 to 16 feet

in most of the borings.

The following table presents general information on the nature of the various soil types

encountered at this site.

Material Encountered Consistency/Density

The FAT CLAY (CH); dark brown and brown, gravelly and with sand. These

materials could undergo high to very high volumetric changes (shrink/swell)

should they experience changes in their in-place moisture content.

Soft to Hard

The LEAN CLAY, SANDY LEAN CLAY (CL); dark brown, brown, and reddish

brown, gravelly, sand. These materials could undergo low to moderate

volumetric changes (shrink/swell) should they experience changes in their in-

place moisture content.

Medium Stiff to Hard

The CLAYEY GRAVEL (GC); dark brown, brown and reddish brown, with clay

seams. This material is primarily granular in nature and could undergo low

volumetric changes (shrink/swell) should it experience changes in its in-place

moisture content. This stratum could be water bearing.

Medium Dense to Very

Dense

The WEATHERED LIMESTONE; tan, materials are expected to be

volumetrically stable Hard

Conditions encountered at each boring location are indicated on the individual boring logs.

Stratification boundaries on the boring logs represent the approximate location of changes in soil

types; in situ, the transition between materials may be gradual. Details for each of the borings

can be found on the boring logs in Appendix A of this report.

3.3 Groundwater

Groundwater generally appears as either a permanent or temporary water source. Permanent

groundwater is generally present year round, which may or may not be influenced by seasonal

and climatic changes. Temporary groundwater water is also referred to as a “perched” water

source, which generally develops as a result of seasonal and climatic conditions.





The borings were dry-augered to their full depths in an attempt to observe for the presence of

subsurface water. Subsurface water was not observed in the borings. Groundwater levels are

influenced by seasonal and climatic conditions which generally result in fluctuations in the

elevation of the groundwater level over time. The clayey gravel can easily transmit water.

Therefore, the foundation contractor should check the groundwater conditions just before

foundation excavation activities. The borings were backfilled with soil cuttings after the drilling

operations and groundwater observations were completed.

4.0 RECOMMENDATIONS FOR DESIGN AND CONSTRUCTION

4.1 Geotechnical Considerations

4.1.1 General

We anticipate that the proposed apartment buildings will be supported by shallow foundation

systems and pier foundations will be used for the proposed parking decks. The desired foundation

system may be used at this site provided the building pads and foundations are designed and

constructed as recommended in this report. Terracon would be pleased to discuss other

foundation alternatives with you upon request.

The foundations being considered must satisfy two independent engineering criteria with respect

to the subsurface conditions encountered at this site. One criterion is the foundation system must

be designed with an appropriate factor of safety to reduce the possibility of a bearing capacity

failure of the soils underlying the foundation when subjected to axial and lateral load conditions.

The other criterion is movement of the foundation system due to compression (consolidation or

shrinkage) or expansion (swell) of the underlying soils must be within tolerable limits for the

structures.

Based on our findings, the subsurface soil/fill at this site exhibits a variable expansion potential.

Based on the information developed from our field and laboratory programs and on method TEX-

124-E in the Texas Department of Transportation (TxDOT) Manual of Testing Procedures, we

estimate that the subgrade soils in the building area exhibit a Potential Vertical Rise (PVR) of

about 1 to 3 inches in its present condition. The actual movements could be greater than the

values presented in this report if inadequate drainage, ponded water, and/or other sources of

moisture are allowed to infiltrate beneath the structure after construction.

4.1.2 Expansive Soil Considerations

Low to highly expansive soils are present on this site. This report provides recommendations to

help mitigate the effects of soil shrinkage and expansion. However, even if these procedures are

followed, some movement and cracking in the structure should be anticipated. The severity of

cracking and other damage such as uneven floor slabs will probably increase if any modification

of the site results in excessive wetting or drying of the expansive soils.





Site grades should provide effective drainage away from the structures during and after

construction. Water permitted to pond next to these structures can result in greater soil

movements than those discussed in this report. These greater movements can result in

unacceptable differential floor slab movements, cracked slabs and walls, and roof leaks.

Estimated movements described in this report are based on effective drainage for the life of the

structures and cannot be relied upon if effective drainage is not maintained. Recommendations

for preparing the building pad to reduce soil movements are provided in the Building Pad

Preparation section of this report. Proper water management is important. Recommendations

regarding this issue are included in the Grading and Drainage section of this report.

4.1.3 Existing Fill Considerations

Onsite Fill Material – FILL thickness ranging between 2 to 7 feet was encountered in the borings

and test pits. The fill material consists of Lean Clay / Fat Clay with Gravel (CL-CH) and Clayey

Gravel (GC). Records for the fill placement were not available for our review. The Standard

Penetration Test (SPT) results and the blow count N-values indicate that the fill was placed under

some compaction effort, but not necessarily with controlled moisture and density. The borings

and test pits performed at the site cannot solely be relied on to evaluate the potential variability of

the FILL. It is possible that different conditions could exist between the boring locations than

those encountered at each bore location. Test Pits were performed at the site which revealed

some debris (boulders, concrete rubble, trash, rebars and metal pipes) in the fill. The contractor

should be aware of such situations. This risk of unforeseen conditions cannot be eliminated

without completely removing the existing fill, but can be reduced by preparing the subgrade as

recommended in this report.

Existing Stock Piles – Test pits were conducted to collect samples from the existing stock piles at

the site. Based on the laboratory results, the stockpiles soil material has plasticity indices ranged

between 30 and 38. Since the materials have high plasticity index, they are not suitable and

should not be considered for use as select fill.

Reuse of Existing Fill Materials – The debris (concrete, boulders, trash, rebars, etc.) varied

between depths of about 2 and 7 feet. Based on our review of the materials, the fill should be

excavated and sorted to remove the debris (boulders, concrete, rebars etc.). As discussed later

a portion of the excavated soil may be reused provided it is free of debris and properly processed.

The excavated soil after removal of debris should be blended to achieve a relatively uniform mix.

The maximum particle size of the prepared material should be 3 inches, or less. The blended soil

can be used to raise grades in pavements and other areas where there are no structures. If used,

the fill should then be placed in compacted lifts of about 6 inches. Each lift should be moisture

conditioned between 0 and +4 percentage points of optimum moisture content and compacted to

98 percent of ASTM D698.

4.1.4 Borrow Pit Area

Based on the provided information, the general area of boring B-19 is proposed to be mined as a

borrow pit area to be used as a select fill for the building pad areas. The boring log designation





and laboratory results indicate 3 feet of clayey gravel fill over 9 feet of native clayey gravel over

weathered limestone. Clayey gravel soils are suitable for use in the building pad as moisture

conditioned and compacted onsite fill material provided they meet the select fill requirements.

4.2 Earthwork

The following presents recommendations for general site preparation, pad preparation and

placement of engineered fills on the project. The recommendation should be reviewed and possibly

revised once the grading and finished floor elevations are available. The recommendations

presented for design and construction of earth supported elements including foundations and

slabs are contingent upon following the recommendations outlined in this section. Earthwork on

the project should be observed and evaluated by Terracon. The evaluation of earthwork should

include observation and testing of engineered fill, subgrade preparation, foundation bearing soils,

and other geotechnical conditions exposed during the construction of the project.

4.2.1 Site Preparation

Construction operations may encounter difficulties due to the wet or soft surface soils becoming

a general hindrance to equipment due to rutting and pumping of the soil surface, especially during

and soon after periods of wet weather. If the subgrade cannot be adequately compacted to

minimum densities as described in the Compaction Requirements section of this report, one of

the following measures may be required: 1) removal and replacement with select fill, 2) chemical

treatment of the soil to dry and increase the stability of the subgrade, or 3) drying by natural means

if the schedule allows. It is the responsibility of the contractor to choose the method required to

access the site.

Prior to placing any fill, all vegetation and any otherwise unsuitable materials should be removed

from the building area. The building area includes the limits of the proposed building and any

abutting flatwork plus a 5-foot (horizontal) overbuild beyond proposed perimeter of the structure

and flatwork. The stripped materials consisting of vegetation and organic materials should be

wasted from the site, or used to revegetate landscaped areas after completion of grading

operations.

After stripping, the subgrade should be proof-rolled to aid in locating loose or soft areas. Proof-

rolling can be performed with a 15-ton roller or fully loaded dump truck. Soft, dry, wet, and low-

density soil should be removed or compacted in place prior to placing fill as described in the

Compaction Requirements section of this report.

4.2.2 Building Pad Preparation

As previously stated, the existing PVRs within the building areas are about 1 to 3 inches in its

present condition. Based on the client request, we have provided a separate subgrade

preparation recommendations for each structure which are intended to reduce the magnitude of

soil movements within each building pad to about 1½ inch. The recommendations below are

based on the FFE at or near the existing grades. The finished building pad elevation FBPE is

assumed to be 0.5 ft below FFE.





Based on the PVR calculation for the existing condition of the on-site soil, the

buildings/structures are divided into three groups based on the amount of removal

and replace with select fill as following;

- Group A (Building 1, 2, 4, Club House, PD-1 and PD-2)

- Group B (Building 3, 5, 7 and 8)

- Group C (Building 6)

Complete stripping operations as discussed in the Site Preparation section.

Excavate and remove completely the existing fill material from each building area

and expose the native soil. The building area is defined as the area extending at

least 5 feet beyond the perimeter of the structure, including any flatwork that abuts

the structure such as sidewalks.

The exposed subgrade in the building areas should be proofrolled with at least a

15-ton roller, or equivalent equipment, to evidence any weak yielding zones. Over-

excavate any confirmed weak yielding zones, both vertically and horizontally, to

expose competent soil. The excavated soil can be used to restore grade provided

that the material is relatively free and clean of deleterious material or materials

exceeding 3 inches in maximum dimension. A Terracon geotechnical engineer or

their representative should be present to observe proofrolling operations.

After proofrolling and the replacement of weak yielding zones, scarify, moisture

condition, and compact the upper 6 inches of the newly exposed subgrade as

described in the Compaction Requirements section.

Place select fill material and on-site moisture conditioned soil to achieve the FBPE

of each building. Moisture condition and compact the select fill as described in the

Compaction Requirements section. Recommendations for select fill are included

in the Material Requirements section. Recommendations for moisture conditioning

and compaction of select fill materials are presented in the Compaction

Requirements section. On-site soil that meets the select fill requirements may be

used.

This will result in variable thicknesses of select fill over moisture conditioned and

compacted on-site soil beneath the various building pads as presented in following

table:

Group Existing PVR (inch) To Achieve 1½ inch PVR1

A 2 to 3 1½’ select Fill

B 1 to 1½ 1½’ select Fill

C 2½ 3’ Select Fill

1 The amount of removal and replacement presented for each group is based on removing

the entire fill material zone from the building/structure pad area.





To provide a more uniform slab support and create a more all-weather working

surface, consideration should be given to constructing the final 6 inches of the pad

with granular select fill. Recommendations for granular select fill are included in the

Material Requirements section of this report.

4.2.3 Material Requirements

Subsequent to proofrolling, and just prior to placement of all structural fill, the exposed subgrade

within the construction area should be evaluated for moisture and density. If the moisture, density,

and/or the requirements do not meet the criteria described in the table below, the subgrade should

be scarified to a depth of 6 inches; moisture adjusted and compacted to at least 95 percent of the

Standard Effort (ASTM D 698) maximum dry density. Select fill and on-site soils should meet the

following criteria.

Fill Type 1 USCS Classification Acceptable Location for Placement

Granular Select Fill 2 Varies Building pad (at least the upper 6 inches)

Onsite Soils meeting

the criteria for Select

Fill or Imported Select

Fill3

CL, GC, SC

(PI 7 to 20)

Suitable for onsite grade changes both inside and

outside of the building pad.

On-Site Soil CH, CL, GC

CH, soils are suitable for use in general grading and

pavement areas. These soils should not be used in

the building pad.

CL, GC, These onsite soils are suitable for use in the

building pad as moisture conditioned and compacted

onsite fill material provided they meet the select fill

requirements.

1 Prior to any filling operations, samples of the proposed borrow and on-site materials should be

obtained for laboratory moisture-density testing. The tests will provide a basis for evaluation of fill

compaction by in-place density testing. A qualified soil technician should perform sufficient in-place

density tests during the filling operations to evaluate that proper levels of compaction, including dry

unit weight and moisture content, are being attained. Controlled, compacted fill should consist of

approved materials that are free of organic matter and debris or materials exceeding 3 inches in

maximum dimension.

2 Granular select fill should consist of cohesive crushed limestone material with a maximum aggregate

size of 3 inches and PI between 5 and 12.

3 Select fill for the building pad should consist of a low plasticity lean clay, gravelly soils, or sandy soils

with a PI between 5 and 20 percent. This material is locally called “pit-run” material and may need to

be imported for this site. Some of the onsite soils may meet the criteria for select fill materials and should

be tested prior to use for this purpose.

4.2.4 Compaction Requirements

Item Description

Fill Lift Thickness All fill should be placed in thin, loose lifts of about 8 inches,

with compacted thickness not exceeding 6 inches.





Item Description

Compaction of Onsite Soil, or Select Fill;

(CH, CL, SC, GC) 95 percent of the material’s Standard Proctor maximum dry density (ASTM D 698).

Moisture Content of Onsite Granular Soil

or Select Fill; (CL, SC, GC) The materials should be moisture conditioned between -2 and +3 percentage points of the optimum moisture content.

Moisture Content of Onsite Clayey Soil The materials should be moisture conditioned between 0 and +4 percentage points of the optimum moisture content.

1 Unless otherwise noted within this report all compaction requirements are provided above.

4.2.5 Grading and Drainage

Effective drainage should be provided during construction and maintained throughout the life of

the development. After building construction and landscaping, we recommend verifying final

grades to document that effective drainage has been achieved. Grades around the structure

should also be periodically inspected and adjusted as necessary, as part of the structure’s

maintenance program.

Water permitted to pond next to the structure can result in distress in the structure including

unacceptable differential floor slab movements, cracked slabs and walls, and roof leaks. Building

slab and foundation performances described in this report are based on effective drainage for the

life of the structure and cannot be relied upon if effective drainage is not maintained.

Flatwork and pavements will be subject to post-construction movement. Maximum grades

practical should be used for paving and flatwork to prevent water from ponding. Allowances in

final grades should also consider post-construction movement of flatwork, particularly if such

movement would be critical. Where paving or flatwork abuts the structure, effectively seal and

maintain joints to prevent surface water infiltration. In areas where sidewalks or paving do not

immediately adjoin the structure, we recommend that protective slopes be provided with a grade

of at least three to five percent for at least 10 feet from perimeter walls (Except in areas where

ADA ramps are required; these should comply with state and local regulations). Backfill against

grade beams, exterior walls, and in utility and sprinkler line trenches should be well compacted

and free of construction debris to reduce the possibility of moisture infiltration.

Planters and other surface features which could retain water in areas adjacent to the structures

should be properly drained, designed, sealed or eliminated. Landscaped irrigation adjacent to the

foundation systems should be properly designed and controlled to help maintain a relatively

constant moisture content within 5 feet of the structure.

Collect roof runoff in drains or gutters. Discharge roof drains and downspouts onto pavements

and/or flatwork which slope away from the structure or extend downspouts a minimum of 5 feet

away from building.





4.2.6 Earthwork Construction Considerations

It is anticipated that excavations for the proposed construction can be accomplished with

conventional earthmoving equipment. Based upon the subsurface conditions determined from the

geotechnical exploration, subgrade soils exposed during construction are anticipated to be

relatively stable. However, the stability of the subgrade may be affected by precipitation, repetitive

construction traffic or other factors. If unstable conditions develop, workability may be improved

by scarifying and drying. Over excavation of wet zones and replacement with granular materials

may be necessary. Lightweight excavation equipment may be required to reduce subgrade

pumping. The use of remotely operated equipment, such as a backhoe, would be beneficial to

perform cuts and reduce subgrade disturbance.

All temporary excavations should be sloped or braced as required by Occupational Health and

Safety Administration (OSHA) regulations to provide stability and safe working conditions.

Temporary excavations will probably be required during grading operations. The grading

contractor, by his contract, is usually responsible for designing and constructing stable, temporary

excavations and should shore, slope or bench the sides of the excavations as required, to

maintain stability of both the excavation sides and bottom. All excavations should comply with

applicable local, state and federal safety regulations, including the current OSHA Excavation and

Trench Safety Standards.

4.3 Foundations

The building may be supported on a shallow slab-on-grade foundation system. Parking decks

may be supported by slab on-grade foundations or drilled pier foundation. Recommendations for

shallow foundation system are provided in the following sections.

4.3.1 Slab-on-Grade Foundation Design Recommendations

Based upon the subsurface conditions observed during our investigation, a shallow foundation

system would be appropriate to support the structural loads of the proposed buildings provided

the subgrade is prepared as discussed in the Building Pad Preparation section of this report.

Parameters commonly used to design this type of foundation are provided on the table below.

The slab foundation design parameters presented on the table below are based on the criteria

published by the Building Research Advisory Board (BRAB) and the Post-Tensioning Institute

(PTI) 3rd Edition. These are essentially empirical design methods and the recommended design

parameters are based on our understanding of the proposed project, our interpretation of the

information and data collected as a part of this study, our area experience, and the criteria

published in the BRAB and PTI design manuals.

Conventional Method Prepared Subgrade 1

Net Allowable Bearing Pressures 2 2,000 psf

Subgrade Modulus (k) 70 pci

Potential Vertical Rise (PVR) 1½ inch





BRAB Methods

Design Plasticity Index (PI) 3 34

Climatic Rating (Cw) 17

Unconfined Compressive Strength 1.0 tsf

Soil Support Index (C) 0.80

PTI Method 3rd Edition

Thornthwaite Moisture Index (Im) -14

Depth of Constant Soil Suction 9 feet

Constant Soil Suction 3.6 pF

Edge Moisture Variation Distance (em):

Center Lift 8.5 feet

Edge Lift 4.2 feet

Differential Soil Movement (ym):

Center Lift 1.5 inches

Edge Lift 1.1 inches

Coefficient of Slab-Subgrade Friction (): 0.75 to 1.00

1 Based on preparing the building pad as discussed in this report.

2 The net allowable bearing pressure provided above includes a Factor of Safety (FS) of at least 3.

We recommend that all grade beams be at least 24 inches below the Finished Building Pad

Elevation (FBPE) which corresponds to 30 inches below the FFE. These recommendations are

for proper development of bearing capacity for the continuous beam sections of the foundation

system and to reduce the potential for water to migrate beneath the slab foundation. These

recommendations are not based on structural considerations. Grade beam depths may need to

be greater than recommended herein for structural considerations and should be properly

evaluated and designed by the Structural Engineer.

For a slab foundation system designed and constructed as recommended in this report, post

construction settlements should be less than 1 inch. Settlement response of a select fill supported

slab is influenced more by the quality of construction than by soil-structure interaction. Therefore,

it is essential that the recommendations for foundation construction be strictly followed during the

construction phases of the building pad and foundation.

The use of a vapor retarder should be considered beneath concrete slabs-on-grade that will be

covered with wood, tile, carpet or other moisture sensitive or impervious coverings, or when the

slabs will support equipment sensitive to moisture. When conditions warrant the use of a vapor

retarder, the slab designer and slab contractor should refer to ACI 302 for procedures and

cautions about the use and placement of a vapor retarder.





4.3.2 Shallow Foundation Construction Considerations

The shallow foundations should preferably be neat excavated. Excavation should be

accomplished with a smooth-mouthed bucket. If a toothed bucket is used, excavation with this

bucket should be stopped 6 inches above the final bearing surface and the excavation completed

with a smooth-mouthed bucket or by hand labor. If neat excavation is not possible then the

foundation should be overexcavated and formed. All loose materials should be removed from the

overexcavated areas and filled with lean concrete or compacted cement stabilized sand (two

sacks cement to one cubic yard of sand) or flowable fill.

Steel should be placed and the foundation poured within 36 hours of excavation. If not, a seal

slab consisting of lean concrete should be poured to protect the exposed foundation soils. The

bearing surface should be excavated with a slight slope to create an internal sump for runoff water

collection and removal. If surface runoff water in excess of 1 inch accumulates at the bottom of

the excavation, it should be pumped out prior to concrete placement. Under no circumstances

should water be allowed to adversely affect the quality of the bearing surface.

Backfill soils above the foundation should consist of select fill. Backfill soils should be placed in

loose 8-inch lifts; moisture conditioned and compacted. Recommendations for select fill are

included in the Material Requirements section of this report.

4.3.3 Drilled Piers Foundation

The parking decks may be supported on drilled piers bearing at a depth no shallower than 15 feet

below existing grade or at least 5 feet into weathered limestone Stratum. Due to the presence of

clayey gravel and limestone, underreamed piers are not recommended.

Drilled piers may be designed for net allowable bearing pressure of 12,000 psf. This bearing

pressure include factor of safety against a bearing capacity failure of approximately 3. An

allowable side shear value of 400 psf, with an assumed factor of safety of at least 2, may be used

to aid in resisting axial compressive loads on the piers. The side shear should be neglected for

the upper 4 feet of soil in contact with the pier shaft. Piers should not extend deeper than 20 feet

below the existing grades at the time of our geotechnical field activities without contacting our

office. Piers should be designed with a shaft diameter at least 18 inches to facilitate inspection.

The allowable end bearing and skin friction values presented in this report are based on center-

to-center spacing of the pier foundations no closer than a horizontal distance of three shaft

diameters (using the larger bearing diameter). A closer spacing may be considered but may effect

(reduce) the axial capacity of the foundation depending on the spacing pattern of the foundations.

Terracon can assist in evaluating the possibility of a closer spacing once a foundation layout has

been determined.

In addition to the axial compressive loads on the piers, these piers will also be subjected to axial

tension loads due to the expansive soil conditions and possibly due to other induced structural

loading conditions. To compute the axial tension force due to the swelling soils along the pier

shaft, the following equation may be used.





Qu = 35·d

Where: Qu = Uplift force due to expansive soil conditions in kips (k)

d = Diameter of pier shaft in feet (ft)

This calculated force may be used to compute the longitudinal reinforcing steel required in the

pier to resist the uplift force induced by the swelling clays. However, the cross-sectional area of

the reinforcing steel should not be less than 1 percent of the gross cross-sectional area of the

drilled pier shaft. The reinforcing steel should extend from the top to the bottom of the shaft to

resist this potential uplift force.

The allowable uplift resistance of the straight sided drilled piers can be evaluated using the

following equation:

Qar = 3.0· d · Dp + 0.9 Wp + PDL

Where: Qar = Allowable uplift resistance of pier in kips (k)

d = Diameter of pier shaft in feet (ft)

Dp = Founding depth of pier in natural soils minus the upper 4

feet of shaft in contact with the soil in feet (ft)

Wp = Weight of the drilled pier in kips (k)

PDL = Dead Load acting on the drilled pier in kips (k)

The structural engineer may want to factor the dead load value based on their degree of certainty.

For adjacent piers, we recommend a minimum center-to-center spacing of at least 3 pier diameter

based on the larger diameter of the two adjacent piers. In locations where this minimum spacing

criterion cannot be accomplished, Terracon should be contacted to evaluate the locations on a

case-by-case basis.

Total settlements, based on the indicated bearing pressures, should be about 1 inch for properly

designed and constructed drilled piers. Settlement beneath individual piers will be primarily elastic

with most of the settlement occurring during construction. Differential settlement may also occur

between adjacent piers. The amount of differential settlement could approach 50 to 75 percent of

the total pier settlement. For properly designed and constructed piers, differential settlement

between adjacent piers is estimated to be less than ¾ of an inch. Settlement response of drilled

piers is impacted more by the quality of construction than by soil-structure interaction.

Improper pier installation could result in differential settlements significantly greater than we have

estimated. In addition, larger magnitudes of settlement should be expected if the soil is subjected

to bearing pressures higher than the allowable values presented in this report.





Lateral Loading - The piers supporting the light poles may be subjected to lateral loading. The

criteria for lateral load analysis is presented in Table 1 are for use with the computer program

LPILE. A number of methods, including hand solutions and computer programs, are available for

calculating the lateral behavior of piles and drilled piers. The majority of these methods rely on

“key” soil parameters such as soil elastic properties (E and ks), strain at 50 percent of the principal

stress difference (50), undrained shear strength (c), and load-deflection (p-y) criteria. The p-y

criteria, which are commonly used to model soil reaction, were developed from instrumented load

tests and are generally considered to provide the best model of soil behavior under short-term

lateral loading.

It should be noted that the initial elastic moduli for soil and rock are referred to as soil modulus (k)

and as initial rock modulus (Eri) on Table 1, and in the LPILE program. The Eri values refer to the

Young’s modulus, in pounds per square inch (psi), as described in the notes of the table. In the

same fashion, the equivalent strain factor for rock materials is referred to as krm.

Factors of safety are not generally applied to the lateral load analysis. A performance criteria, or

“limit state”, are usually considered. For most foundations subjected to lateral loads, the pier

foundation is designed with a limit of 1 inch of deflection at the top of the pier and 1 degree of

rotation as measured from the vertical axis of the pier. The analysis is generally conducted using

the working loads and the limit state values. The applied loads are then doubled to evaluate the

deflection and rotation at the top of the pier to determine if the foundation will topple over under

extreme overload. This overload condition may indicate that the foundation would deflect or rotate

such that the tower will tilt but the foundation will not experience failure. Structural limits, such as

moment capacity and shear, may control the design and should be evaluated by the Structural

Engineer.

4.3.4 Drilled Pier Construction Considerations

The pier excavations should be augered and constructed in a continuous manner. Steel and

concrete should be placed in the pier excavations immediately following drilling and evaluation

for proper bearing stratum, embedment, and cleanliness. Under no circumstances should the pier

excavations remain open overnight. Due to the presence of limestone; high torque, high

powered (rock) drilling equipment will be required.

During the time of our drilling operations, subsurface water was not encountered. Subsurface

water levels are influenced by seasonal and climatic conditions which result in fluctuations in

subsurface water elevations. Clayey Gravel were also encountered during drilling. Therefore

caving of the pier walls during excavation should be anticipated. Therefore, the contractor should

be prepared to use temporary casing should water be encountered and/or sloughing of the

excavation sidewalls occur. It is the responsibility of the foundation contractor to choose the

casing, type, depth and method of installation. The casing method is discussed in the following

paragraphs.





Casing Method- Casing should provide stability of the excavation walls and should

reduce water influx; however, casing may not completely eliminate subsurface water

influx potential. In order for the casing to be effective, a “water tight” seal must be

achieved between the casing and surrounding soils. The drilling subcontractor

should determine casing depths and casing procedures. Water that accumulates in

excess of 3 inches in the bottom of the pier excavation should be pumped out prior

to steel and concrete placement. If the water is not pumped out, a closed-end tremie

should be used to place the concrete completely to the bottom of the pier excavation

in a controlled manner to effectively displace the water during concrete placement.

If water is not a factor, concrete may be placed with a short tremie so the concrete

is directed to the bottom of the pier excavation. The concrete should not be allowed

to ricochet off the walls of the pier excavation nor off the reinforcing steel. If this

operation is not successful or to the satisfaction of the foundation contractor, the pier

excavation should be flooded with fresh water to offset the differential water pressure

caused by the unbalanced water levels inside and outside of the casing. The

concrete should be tremied completely to the bottom of the excavation with a closed-

end tremie.

Removal of casing should be performed with extreme care and under proper

supervision to reduce mixing of the surrounding soil and water with the fresh

concrete. Rapid withdrawal of casing or the auger may develop suction that could

cause the soil to intrude into the excavation. An insufficient head of concrete in the

casing during its withdrawal could also allow the soils to intrude into the wet concrete.

Both of these conditions may induce “necking”, a section of reduced diameter, in the

pier.

All aspects of concrete design and placement should comply with the American Concrete Institute

(ACI) 318 Code Building Code Requirements for Structural Concrete, ACI 336.1 Standard

Specification for the Construction of Drilled Piers, and ACI 336.3R entitled Suggested Design and

Construction Procedures for Pier Foundations. Concrete should be designed to achieve the

specified minimum 28-day compressive strength when placed at a 7 inch slump with a 1 inch

tolerance. Adding water to a mix designed for a lower slump does not meet the intent of this

recommendation. If a high range water reducer is used to achieve this slump, the span of slump

retention for the specific admixture under consideration should be thoroughly investigated.

Compatibility with other concrete admixtures should also be considered. A technical

representative of the admixture supplier should be consulted on these matters.

Successful installation of drilled piers is a coordinated effort involving the general contractor,

design consultants, subcontractors and suppliers. Each must be properly equipped and prepared

to provide their services in a timely fashion. Several key items are:

Proper drilling rig with proper equipment (including high torque, high powered rock

drilling equipment).





Reinforcing steel cages tied to meet project specifications;

Proper scheduling and ordering of concrete for the piers; and

Monitoring of installation by design professionals.

Pier construction should be carefully monitored to assure compliance of construction activities

with the appropriate specifications. A number of items recommended for monitoring during pier

installation include those listed below.

Pier locations Concrete properties and placement

Vertical alignment Casing removal (if required)

Competent bearing Proper casing seal for subsurface water control

Steel placement

If the contractor has to deviate from the recommended foundations, Terracon should be notified

immediately so additional engineering recommendations can be provided for an appropriate

foundation type.

4.3.5 Foundation Construction Monitoring

The performance of the foundation system for the proposed structure will be highly dependent

upon the quality of construction. Thus, we recommend that fill pad compaction and foundation

installation be monitored by an experienced Terracon soil technician under the direction of our

Geotechnical Engineer. We would be pleased to develop a plan for compaction and foundation

installation monitoring to be incorporated in the overall quality control program.

4.4 Seismic Considerations

Description Value

2012 International Building Code Site Classification (IBC) 1 C 2

Site Latitude (Degrees) 29.62234°N

Site Longitude (Degrees) 98.60414°W

Mapped Spectral Acceleration for Short Periods (0.2-Second): (SS) 3 0.072g

Mapped Spectral Acceleration for a 1-Second Period: (S1) 3 0.030g

1 The site class definition was determined using SPT N-values in conjunction with section 1613.3.2 in

the 2012 IBC and Table 20.3-1 in the 2010 ASCE-7.

2 Borings extended to a maximum depth of 25 feet, and this seismic site class definition considers that

Hard soil continues below the maximum depth of the subsurface exploration.

3 The Spectral Acceleration values were determined using publicly available information provided on

the United States Geological Survey (USGS) website. The spectral acceleration values can be used

to determine the site coefficients using Tables 1613.3.3 (1) and 1613.3.3 (2) in the 2012 IBC.





4.5 Swimming Pool

The proposed swimming pool walls will be subject to lateral earth pressures induced by the soil

retained by those walls, and should consider the drainage conditions behind the wall. Swimming

pool walls should be designed to resist “at rest” earth pressures due to their generally non-yielding

nature.

If the pool is constructed using a “gunite” technique, then the equivalent fluid density will be

dictated by the natural soil. With the gunite method, installation of drainage material is not

practical. Therefore, the design pressures should consider full hydrostatic conditions behind the

wall.

If the soils are mass excavated and the swimming pool is formed and placed, then the backfill can

consist of select materials such as clean, free-draining sand or gravel, which will allow the

equivalent fluid density exerted on the pool walls to be controlled to some extent. The select

granular fill should extend behind the heel of the wall and extend upward to the ground surface at

an angle of 45 degrees or flatter. If the pool walls are backfilled with select granular fill, then a

drainage system comprised of slotted or perforated PVC pipe encased by clean sand or gravel

that is completely wrapped in filter fabric should be considered for behind-wall construction to

further control the equivalent fluid density. However, if this drainage system fails to perform as

intended, then full hydrostatic pressures may occur.

The following equivalent fluid densities may be used for the design of the swimming pool walls at

this site depending upon whether or not reliable drainage is provided behind the wall. The

following equivalent fluid densities do not account for any surcharge loads.

Retained Material Type

Drainage Condition

Equivalent Fluid Density (pcf)

With Hydrostatic Forces Without Hydrostatic Forces

Clayey Gravel 95 65

Lean Clay Soil 100 80

Free-Draining Sand/Gravel 90 55

We recommend that the walls of the pool be designed assuming no pressure from the water in

the pool; i.e. an empty pool.

4.6 Pavements

Both flexible and rigid pavement systems may be considered for the project. Based on our

knowledge of the project, we anticipate that traffic loads will be produced primarily by automobile

traffic and occasional delivery and trash removal trucks.





4.6.1 Subgrade Preparation

Prior to placing any fill, vegetation and any otherwise unsuitable materials should be removed

from the new pavement areas. After stripping, the subgrade should be proof-rolled to aid in

locating loose or soft areas. Proof-rolling can be performed with a 15-ton roller or fully loaded

dump truck. Wet, soft, low-density or dry material should either be removed or moisture

conditioned and recompacted to the moisture contents and densities described in the

Compaction Requirements section prior to placing fill.

4.6.2 Design Considerations

For this project Light and Heavy pavement section alternatives have been provided. A light section

is for areas expected to receive only car traffic. A heavy section assumes areas with heavy traffic,

such as trash pickup areas and main access drive areas.

The flexible pavement section was designed in general accordance with the National Asphalt

Pavement Association (NAPA) Information Series (IS-109) method (Class 1 for Light and Class

2 for Heavy). The rigid pavement section was designed using the American Concrete Institute

(ACI 330R-01) method (Traffic Category A (ADTT=0) for Light and A-1 (ADTT=10) for Heavy). If

heavier traffic loading is expected, Terracon should be provided with the information and allowed to

review these pavement sections.

FLEXIBLE PAVEMENT SYSTEM (inches)

Raw Subgrade Modified Subgrade

Light

Duty

Heavy

Duty

Dumpster

Location

Light

Duty

Heavy

Duty

Dumpster

Location

Hot Mix Asphaltic Concrete 2.0 2.5 NR 2 2.0 2.5 NR 2

Base Material 1 10.0 14.0 NR 2 6.0 10.0 NR 2

Modified Subgrade3 ---- ---- NR 2 6.0 6.0 NR 2

Moisture Conditioned Subgrade 6.0 6.0 NR 2 ---- ---- NR 2

1 Asphaltic base material may be used in place of crushed limestone base material. Every 2.5 inches

of crushed limestone base material may be replaced with 1 inch of asphaltic base material. However,

the minimum thickness of the asphaltic base material is 4 inches.

2 NR = Not Recommended

3 As an alternative to a lime treated subgrade beneath the flexible pavements, a geogrid such as

Tensar BX-1100 or Tensar TX-140 may be used at the interface between the subgrade soils and the

base material.





RIGID PAVEMENT SYSTEM (inches)

Raw Subgrade Modified Subgrade

Light

Duty

Heavy

Duty

Dumpster

Location

Light

Duty

Heavy

Duty

Dumpster

Location

Reinforced Concrete 5.5 6.5 7.0 5.0 6.0 6.5

Modified Subgrade ---- ---- ---- 6.0 6.0 6.0

Moisture Conditioned Subgrade 6.0 6.0 6.0 ---- ---- ----

The pavement subgrade is expected to consist of natural undisturbed soils or fill material in cut

areas, and fill utilizing soils taken from the cut to raise grades where required. Proper perimeter

drainage is very important and should be provided so infiltration of surface water from unpaved

areas surrounding the pavement is minimized. We do not recommend installation of landscape

beds or islands in the pavement areas. Such features provide an avenue for water to enter into

the pavement section and underlying soil subgrade. Water penetration usually results in

degradation of the pavement section with time as vehicular traffic traverses the affected area.

Therefore, positive drainage should be established and maintained throughout the life of the

pavement.

Curbs should extend through the base and at least 3 inches into the soil subgrade below the base

course. This will help reduce migration of subsurface water into the pavement base course from

adjacent areas. A crack sealant compatible to both asphalt and concrete should be provided at

all concrete-asphalt interfaces.

Pavement areas that will be subjected to heavy wheel and traffic volumes, such as waste bin or

"dumpster" areas, entrance/exit ramps, and delivery areas, should be a rigid pavement section

constructed of reinforced concrete. The concrete pavement areas should be large enough to

properly accommodate the vehicular traffic and loads. For example:

The dumpster pad should be large enough so that the wheels of the collection

truck are entirely supported on the concrete pavement during lifting of the waste

bin; and

The concrete pavement should extend beyond any areas that require extensive

turning, stopping, and maneuvering.

The pavement design engineer should consider these and other similar situations when planning

and designing pavement areas. Waste bin and other areas that are not designed to accommodate

these situations often result in localized pavement failures.

The pavement section has been designed using generally recognized structural coefficients for

the pavement materials. These structural coefficients reflect the relative strength of the pavement

materials and their contribution to the structural integrity of the pavement. If the pavement does

not drain properly, it is likely that ponded water will infiltrate the pavement materials resulting in a





weakening of the materials. As a result, the structural coefficients of the pavement materials will

be reduced and the life and performance of the pavement will be shortened. The Asphalt Institute

recommends a minimum of 2 percent slope for asphalt pavements. The importance of proper

drainage cannot be overemphasized and should be thoroughly considered by the project team.

4.6.3 Pavement Section Materials

Hot Mix Asphaltic Concrete Surface Course - The asphaltic concrete surface

course should be plant mixed, hot laid Type C or D Surface. The asphaltic concrete

base course should also be plant mixed, hot laid Type A or B. Each mix should

meet the master specifications requirements of 2004 TXDOT Standard

Specifications Item 341, Item SS 3224 (2011) and specific criteria for the job mix

formula. The mix should be compacted between 91 and 95 percent of the

maximum theoretical density as measured by TEX-227-F. The asphalt cement

content by percent of total mixture weight should fall within a tolerance of ±0.3

percent asphalt cement from the specific mix. In addition, the mix should be

designed so 75 to 85 percent of the voids in the mineral aggregate (VMA) are filled

with asphalt cement. The grade of the asphalt cement should be PG 64-22 or

higher performance grade. Aggregates known to be prone to stripping should not

be used in the hot mix. If such aggregates are used measures should be taken to

mitigate this concern. The mix should have at least 70 percent strength retention

when tested in accordance with TEX-531-C.

Pavement specimens, which shall be either cores or sections of asphaltic

pavement, will be tested according to Test Method TEX-207-F. The nuclear-

density gauge or other methods which correlate satisfactorily with results obtained

from project pavement specimens may be used when approved by the Engineer.

Unless otherwise shown on the plans, the Contractor shall be responsible for

obtaining the required pavement specimens at their expense and in a manner and

at locations selected by the Engineer.

Concrete - Concrete should have a minimum 28-day design compressive strength

of 4,000 psi.

Granular Base Material Base material may be composed of crushed limestone

base/ crushed concrete meeting all of the requirements of 2004 TxDOT Item 247,

Type A or D, Grade 1 or 2; including triaxial strength.

Asphaltic Base Course - The asphaltic base material should meet the

specification requirements of 2004 TxDOT Standard Specification Item 340, Type

A or B.





Modified Subgrade - Due to the presence of clay at this site, the subgrade may

be treated with hydrated lime in accordance with TxDOT Item 260 in order to

improve its strength and improve its load carrying capacity. If granular soils are

exposed in the subgrade, cement may be used. If a modified subgrade is chosen,

the subgrade soils should be tested for sulfates due to the possibility of a reaction

between the calcium-based modifiers and sulfates in the soil.

We anticipate that approximately 6 percent hydrated lime will be required. This is

equivalent to about 27 pounds of hydrated lime per square yard for a 6 inch

treatment depth. However, the actual percentage should be determined by

laboratory tests on samples of the clayey subgrade prior to construction. The

optimum lime content should result in a soil-lime mixture with a pH of at least 12.4

when tested in accordance with ASTM C 977, Appendix XI and should reduce the

Plasticity Index to 20 or less.

For lime-treated subgrade, the lime should initially be blended with a mixing device

such as a Pulvermixer, sufficient water added, and be allowed to cure for at least

48 hours. After curing, the lime-soil should be remixed to meet the in-place

gradation requirements of Item 260 and compacted to at least 95 percent of the

maximum dry density determined in accordance with ASTM D 698 at moisture

contents ranging from optimum and 4 percentage points above the optimum

moisture content.

Moisture Conditioned Subgrade - The subgrade should be scarified to a depth

of 6 inches and then moisture conditioned and compacted as recommended in the

Compaction Requirements section of this report.

Details regarding subgrade preparation, fill materials, placement and compaction are presented

in the Earthwork section under the Material Requirements and Compaction Requirements

subsections.

4.6.4 Pavement Joints and Reinforcement

The following is recommended for all concrete pavement sections in this report. Refer to ACI 330

“Guide for Design and Construction of Concrete Parking Lots” for additional information.

Contraction Joint Spacing: 12½ feet each way for pavement thickness of 5 or 5½

inches; 15 feet each way for pavement thickness of 6 or

greater.

Contraction Joint Depth: At least ¼ of pavement thickness.

Contraction Joint Width: One-fourth inch or as required by joint sealant

manufacturer.





Construction Joint Spacing: To attempt to limit the quantity of joints in the pavement,

consideration can be given to installing construction joints at

contraction joint locations, where it is applicable.

Construction Joint Depth/Width: Full depth of pavement thickness. Construct sealant

reservoir along one edge of the joint. Width of reservoir to

be ¼ inch or as required by joint sealant manufacturer.

Depth of reservoir to be at least ¼ of pavement thickness.

Isolation Joint Spacing: As required to isolate pavement from structures, etc.

Isolation Joint Depth: Full depth of pavement thickness.

Isolation Joint Width: One-half to 1 inch or as required by the joint sealant

manufacturer.

Expansion Joint: None (see note below)

Note: Long, linear pavements may require expansion joints. However, in this locale, drying

shrinkage of concrete typically significantly exceeds anticipated expansion due to

thermal affects. As a result, the need for expansion joints is eliminated provided all

joints (including saw cuts) are sealed. Construction of an unnecessary joint may be

also become a maintenance problem. All joints should be sealed. If all joints, including

sawcuts, are not sealed then expansion joints should be installed.

Distributed Steel: Steel reinforcement may consist of steel bars described as follows:

No 3 reinforcing steel bars at 18 inches on-center-each-way, Grade 60.

No 4 reinforcing steel bars at 24 inches on-center-each-way, Grade 60.

Note: It is imperative that the distributed steel be positioned accurately in the pavement cross

section, namely 2 inches from the top of the pavement.

All construction joints have dowels. Dowel information varies with pavement thickness as

presented as follows:

Pavement Thickness: 5, 5½ inches 6, 6½ inches 7 inches

Dowels: ⅝ inch diameter ¾ inch diameter ⅞ inch diameter

Dowel Spacing: 12 inches on center 12 inches on center 12 inches on center

Dowel Length: 12 inches long 14 inches long 14 inches long

Dowel Embedment: 5 inches 6 inches 6 inches





5.0 GENERAL COMMENTS

Terracon should be retained to review the final design plans and specifications so comments can

be made regarding interpretation and implementation of our geotechnical recommendations in the

design and specifications. Terracon also should be retained to provide observation and testing

services during grading, excavation, foundation construction and other earth-related construction

phases of the project.

The analysis and recommendations presented in this report are based upon the data obtained

from the borings performed at the indicated locations and from other information discussed in this

report. This report does not reflect variations that may occur between borings, across the site, or

due to the modifying effects of construction or weather. The nature and extent of such variations

may not become evident until during or after construction. If variations appear, we should be

immediately notified so that further evaluation and supplemental recommendations can be

provided. Prospective contractors should familiarize themselves with the conditions at the site and

retain their own experts to interpret the data in this report and perform additional testing and/or

inspection as they deem necessary prior to bidding.

The scope of services for this project does not include either specifically or by implication any

environmental or biological (e.g., mold, fungi, bacteria) assessment of the site or identification or

prevention of pollutants, hazardous materials or conditions. If the owner is concerned about the

potential for such contamination or pollution, other studies should be undertaken.

This report has been prepared for the exclusive use of our client for specific application to the

project discussed and has been prepared in accordance with generally accepted geotechnical

engineering practices. No warranties, either express or implied, are intended or made. Site

safety, excavation support, and dewatering requirements are the responsibility of others. In the

event that changes in the nature, design, or location of the project as outlined in this report are

planned, the conclusions and recommendations contained in this report shall not be considered

valid unless Terracon reviews the changes and either verifies or modifies the conclusions of this

report in writing.




Reliable ■ Resourceful ■ Responsive Table 1

TABLE 1

LATERAL DESIGN PARAMETERS

AMARA APARTMENTS AT THE RIM

TALAVERA RIDGE AND OLD CAMP BULLIS ROAD

SAN ANTONIO, TEXAS

TERRACON PROJECT NO. 90165068

Layer

Depth to

Bottom

of Layer

(feet)

Total Unit

Weight

(pcf)

Effective

Unit Weight

(pcf)

Undrained

Shear Strength

(psf)

Soil Strain

Factor

(50)

LPILE Soil Types

Friction Angle

(degrees)

RQD (%)5

Subgrade

Modulus, k6

(pci)

1 4 120 120 1,000 0.010 Stiff Clay without Water --- --- 425

2 12 115 115 --- --- Sand 32 --- 129

3 25 130 130 100 psi4 0.0005 Weak Rock --- 20 70,000

1 Design depth to subsurface water is below 25 feet.

2 Stratigraphy shown above is based on our interpretation of soil strength and may not correspond with the descriptive classifications shown on the boring logs.

3 The lateral load criteria shown above are for use in the computer programs LPILE.

4 Uniaxial compressive strength of rock is in psi.

5 RQD value is assumed.

6 K-value given for Weak Rock is Eri in psi.

APPENDIX A

SITE LOCATION PLAN

Amara Apartments at the Rim Talavera Ridge and Old Camp Bullis Road

San Antonio, Texas

6911 Blanco Rd

San Antonio, TX 78216-6164

90165068

AERIAL PHOTOGRAPHY PROVIDED BYGOOGLE EARTH

Project Manager:

Drawn by:

Checked by: Approved by:

TA

AW

GPS

AW

6/17/2016

Exhibits

Project No.

File Name: Date:

A-1

Exhibit

As Shown Scale:

B-1

- Approximate Boring Location Surface Condition

B-17

B-5

B-10 B-9 B-8 B-7

B-3

B-2

B-11 B-12

B-13

B-18

B-14

B-6

B-19

B-16

B-4

B-15 1

2

Amara Apartments at the Rim Talavera Ridge and Old Camp Bullis Road

San Antonio, Texas

3

5

DIAGRAM IS FOR GENERAL LOCATION ONLY, AND IS NOT INTENDED FOR CONSTRUCTION

PURPOSES

4

6 7

8

PD-1

TA

PD-2

AW

GPS

AW

Exhibits

6/17/2016

B-20

BORING LOCATION PLAN

- Building Number Surface Condition

6911 Blanco Rd

San Antonio, TX 78216-6164

90165068 Project Manager:

Drawn by:

Checked by: Approved by:

Scale:

Project No.

File Name: Date:

NTS A-2

Exhibit

TP-1 TP-2

TP-3

- Approximate Test Pit Location Terracon Project No. 90155270

Surface Condition




Reliable ■ Resourceful ■ Responsive Exhibit A-3

Field Exploration Description

Terracon personnel used the site plan provided by the client, to establish the bore locations in the

field. The bore locations were located in the field using a hand-held GPS device. A copy of the

Bore Location Plan indicating the approximate boring locations is included in Appendix A. The

location of the boring should be considered accurate only to the degree implied by the means and

methods used to define them.

A truck-mounted, rotary drill rig equipped with continuous flight augers was used to advance the

boreholes. Soil samples were obtained by both thin-walled tube and split-barrel sampling

procedures. In the thin-walled tube sampling procedure, a thin-walled, seamless tube with a

sharp cutting edge is pushed hydraulically into the ground to obtain relatively undisturbed samples

of cohesive or moderately cohesive soils. In the split-barrel sampling procedure, a standard 2-

inch O.D. split-barrel sampling spoon is driven into the ground with a 140-pound hammer falling

a distance of 30 inches. The number of blows required to advance the sampling spoon the last

12 inches of a normal 18-inch penetration is recorded as the standard penetration resistance

value. These values are indicated on the borings logs at the depths of occurrence. The samples

were sealed and transported to the laboratory for testing and classification. Also test pits were

conducted at the site to a certain depth to observe the depth of the fill material using a backhoe

with an operator provided by the client. The test pits were backfilled upon completion using the

excavated material.

Our field representative prepared the field logs as part of the drilling operations. The field logs

included visual classifications of the materials encountered during drilling and our field

representative interpretation of the subsurface conditions between samples. Each boring log

included with this report represents the engineer’s/geologist’s interpretation of the field logs and

include modifications based on visual observations and testing of the samples in the laboratory.

N=Ref/2" sampler could only be driven 2 inches of the 6 inchseating penetration before the 50 blow limit was reached

24

26

13

3

2

2

5

5

69-23-466-2-6N=8

19-50/4"N=50/4"

12-6-13N=19

28-50/4"N=50/4"

28-50/1"N=50/1"

50/2"N=Ref/2"

50/1"N=Ref/1"

5.0

8.0

20.0

FILL: FAT CLAY (CH)dark brown, stiff to hard with coarse gravel

- turns to brown below 3 feet

CLAYEY GRAVEL (GC)brown to reddish brown, very dense

WEATHERED LIMESTONEtan, hard

Boring Terminated at 20 Feet

Hammer Type: AutomaticStratification lines are approximate. In-situ, the transition may be gradual.

GR

AP

HIC

LO

G

TH

IS B

OR

ING

LO

G IS

NO

T V

ALI

D IF

SE

PA

RA

TE

D F

RO

M O

RIG

INA

L R

EP

OR

T.

G

EO

SM

AR

T L

OG

-NO

WE

LL 9

016

506

8.G

PJ

Talavera Ridge and Old Camp Bullis Road San Antonio, TexasSITE:

Page 1 of 1

Advancement Method:Auger 0 to 10'Air Rotary 10 to 20'

Abandonment Method:Borings backfilled with soil cuttings upon completion.

6911 Blanco RdSan Antonio, TX

Notes:

Project No.: 90165068

Drill Rig: CME 45C

Boring Started: 4/26/2016

BORING LOG NO. B-1Oden Hughes LLCCLIENT:Austin Texas

Driller: Ramco

Boring Completed: 4/26/2016

Exhibit: A-4

PROJECT: Amara Apartment at the Rim

PE

RC

EN

T F

INE

S

WA

TE

RC

ON

TE

NT

(%

)

ATTERBERGLIMITS

LL-PL-PI

SA

MP

LE T

YP

E

WA

TE

R L

EV

EL

OB

SE

RV

AT

ION

S

DE

PT

H (

Ft.)

5

10

15

20

FIE

LD T

ES

TR

ES

ULT

S

DEPTH

LOCATION See Exhibit A-2

Latitude: 29.623392° Longitude: -98.605627°

No free water observedWATER LEVEL OBSERVATIONS


45

25

15

11

26

13

4

4

8

26-16-10

6-8-9N=17

22-50/3"N=50/3"

7-6-3N=9

9-21-24N=45

50/2"N=Ref/2"

50/2"N=Ref/2"

50/1"N=Ref/1"

6.0

8.0

20.0

FILL: LEAN CLAY (CL)brown, stiff to hard, gravelly

CLAYEY GRAVEL (GC)reddish brown, dense


- turns to gray below 17 feet



GR

AP

HIC

LO

G

TH

IS B

OR

ING

LO

G IS

NO

T V

ALI

D IF

SE

PA

RA

TE

D F

RO

M O

RIG

INA

L R

EP

OR

T.

G

EO

SM

AR

T L

OG

-NO

WE

LL 9

016

506

8.G

PJ


Page 1 of 1




Notes:


Drill Rig: CME 45C



Driller: Ramco


Exhibit: A-5


PE

RC

EN

T F

INE

S

WA

TE

RC

ON

TE

NT

(%

)

ATTERBERGLIMITS

LL-PL-PI

SA

MP

LE T

YP

E

WA

TE

R L

EV

EL

OB

SE

RV

AT

ION

S

DE

PT

H (

Ft.)

5

10

15

20

FIE

LD T

ES

TR

ES

ULT

S

DEPTH





91

59

11

29

30

10

21

7

8

79-28-51

15-12-7N=19

7-6-7N=13

6-12-13N=25

22-29-19N=48

11-21-36N=57

50/1"N=Ref/1"

50/1"N=Ref/1"

7.0

11.0

20.0

FILL: FAT CLAY (CH)brown, stiff to hard, gravelly

CLAYEY GRAVEL (GC)reddish brown, very dense




GR

AP

HIC

LO

G

TH

IS B

OR

ING

LO

G IS

NO

T V

ALI

D IF

SE

PA

RA

TE

D F

RO

M O

RIG

INA

L R

EP

OR

T.

G

EO

SM

AR

T L

OG

-NO

WE

LL 9

016

506

8.G

PJ


Page 1 of 1




Notes:


Drill Rig: CME 45C



Driller: Ramco


Exhibit: A-6


PE

RC

EN

T F

INE

S

WA

TE

RC

ON

TE

NT

(%

)

ATTERBERGLIMITS

LL-PL-PI

SA

MP

LE T

YP

E

WA

TE

R L

EV

EL

OB

SE

RV

AT

ION

S

DE

PT

H (

Ft.)

5

10

15

20

FIE

LD T

ES

TR

ES

ULT

S

DEPTH





34

24

18

8

12

15

6

7

7

34-18-16

25-19-6

6-6-8N=14

8-9-15N=24

3-3-3N=6

16-15-14N=29

8-12-15N=27

50/2"N=Ref/2"

50/2"N=Ref/2"

6.0

12.0

20.0

FILL: LEAN CLAY (CL)dark brown, medium stiff to very stiff, sandy

- with gravel layer between 2 and 4 feet- turns to brown below 4 feet

CLAYEY GRAVEL (GC)reddish brown, medium dense




GR

AP

HIC

LO

G

TH

IS B

OR

ING

LO

G IS

NO

T V

ALI

D IF

SE

PA

RA

TE

D F

RO

M O

RIG

INA

L R

EP

OR

T.

G

EO

SM

AR

T L

OG

-NO

WE

LL 9

016

506

8.G

PJ


Page 1 of 1




Notes:


Drill Rig: CME 45C



Driller: Ramco


Exhibit: A-7


PE

RC

EN

T F

INE

S

WA

TE

RC

ON

TE

NT

(%

)

ATTERBERGLIMITS

LL-PL-PI

SA

MP

LE T

YP

E

WA

TE

R L

EV

EL

OB

SE

RV

AT

ION

S

DE

PT

H (

Ft.)

5

10

15

20

FIE

LD T

ES

TR

ES

ULT

S

DEPTH





21

23

15

16

14

9

5

6

69-29-403-4-5N=9

5-7-8N=15

8-15-13N=28

8-10-35N=45

16-21-27N=48

50/3"N=Ref/3"

50/1"N=Ref/1"

5.0

10.0

20.0

FILL: FAT CLAY (CH)dark brown, stiff to very stiff

CLAYEY GRAVEL (GC)reddish brown, medium dense to dense

- layer of marly clay below 8 feet




GR

AP

HIC

LO

G

TH

IS B

OR

ING

LO

G IS

NO

T V

ALI

D IF

SE

PA

RA

TE

D F

RO

M O

RIG

INA

L R

EP

OR

T.

G

EO

SM

AR

T L

OG

-NO

WE

LL 9

016

506

8.G

PJ


Page 1 of 1




Notes:


Drill Rig: CME 45C



Driller: Ramco


Exhibit: A-8


PE

RC

EN

T F

INE

S

WA

TE

RC

ON

TE

NT

(%

)

ATTERBERGLIMITS

LL-PL-PI

SA

MP

LE T

YP

E

WA

TE

R L

EV

EL

OB

SE

RV

AT

ION

S

DE

PT

H (

Ft.)

5

10

15

20

FIE

LD T

ES

TR

ES

ULT

S

DEPTH





36

21

17

37

31

12

7

6

64-29-35

78-37-41

2-2-4N=6

16-15-10N=25

6-8-10N=18

15-50/5"N=50/5"

27-17-8N=25

50/5"N=Ref/5"

50/2"N=Ref/2"

6.0

9.0

12.0

20.0

FILL: FAT CLAY (CH)dark brown, medium stiff to very stiff, gravelly

FAT CLAY (CH)dark brown, very stiff to hard

CLAYEY GRAVEL (GC)reddish brown, medium dense




GR

AP

HIC

LO

G

TH

IS B

OR

ING

LO

G IS

NO

T V

ALI

D IF

SE

PA

RA

TE

D F

RO

M O

RIG

INA

L R

EP

OR

T.

G

EO

SM

AR

T L

OG

-NO

WE

LL 9

016

506

8.G

PJ


Page 1 of 1




Notes:


Drill Rig: CME 45C



Driller: Ramco


Exhibit: A-9


PE

RC

EN

T F

INE

S

WA

TE

RC

ON

TE

NT

(%

)

ATTERBERGLIMITS

LL-PL-PI

SA

MP

LE T

YP

E

WA

TE

R L

EV

EL

OB

SE

RV

AT

ION

S

DE

PT

H (

Ft.)

5

10

15

20

FIE

LD T

ES

TR

ES

ULT

S

DEPTH





60

20

5

10

10

12

12

8

7

29-14-15

28-16-12

40-16-24

12-20-15N=35

3-18-34N=52

24-24-24N=48

13-22-47N=69

12-32-50/3"N=82/9"

7-50/3"N=50/3"

50/5"N=Ref/5"

7.0

12.0

20.0

FILL: LEAN CLAY (CH)brown, hard, gravelly





GR

AP

HIC

LO

G

TH

IS B

OR

ING

LO

G IS

NO

T V

ALI

D IF

SE

PA

RA

TE

D F

RO

M O

RIG

INA

L R

EP

OR

T.

G

EO

SM

AR

T L

OG

-NO

WE

LL 9

016

506

8.G

PJ


Page 1 of 1




Notes:


Drill Rig: CME 45C



Driller: Ramco


Exhibit: A-10


PE

RC

EN

T F

INE

S

WA

TE

RC

ON

TE

NT

(%

)

ATTERBERGLIMITS

LL-PL-PI

SA

MP

LE T

YP

E

WA

TE

R L

EV

EL

OB

SE

RV

AT

ION

S

DE

PT

H (

Ft.)

5

10

15

20

FIE

LD T

ES

TR

ES

ULT

S

DEPTH





63

8

10

8

5

7

9

8

25-14-11

18-12-11N=23

5-4-7N=11

6-21-50/5"N=71/11"

38-50/5"N=50/5"

50/2"N=Ref/2"

14-16-22N=38

50/3"N=Ref/3"

6.0

20.0

FILL: SANDY LEAN CLAY (CL)brown, stiff to hard, gravelly




GR

AP

HIC

LO

G

TH

IS B

OR

ING

LO

G IS

NO

T V

ALI

D IF

SE

PA

RA

TE

D F

RO

M O

RIG

INA

L R

EP

OR

T.

G

EO

SM

AR

T L

OG

-NO

WE

LL 9

016

506

8.G

PJ


Page 1 of 1




Notes:


Drill Rig: CME 45C



Driller: Ramco


Exhibit: A-11


PE

RC

EN

T F

INE

S

WA

TE

RC

ON

TE

NT

(%

)

ATTERBERGLIMITS

LL-PL-PI

SA

MP

LE T

YP

E

WA

TE

R L

EV

EL

OB

SE

RV

AT

ION

S

DE

PT

H (

Ft.)

5

10

15

20

FIE

LD T

ES

TR

ES

ULT

S

DEPTH





84

11

10

34

26

27

12

13

25-16-9

61-26-35

38-17-21

4-10-14N=24

16-9-8N=17

3-1-2N=3

7-8-10N=18

HP= 4.5+

HP= 4.5+

50/2"N=Ref/2"

4.0

12.0

20.0

FILL: LEAN CLAY (CH)brown, hard, gravelly

FAT CLAY (CH)dark brown, soft to hard


LEAN CLAY (CL)reddish brown, hard



GR

AP

HIC

LO

G

TH

IS B

OR

ING

LO

G IS

NO

T V

ALI

D IF

SE

PA

RA

TE

D F

RO

M O

RIG

INA

L R

EP

OR

T.

G

EO

SM

AR

T L

OG

-NO

WE

LL 9

016

506

8.G

PJ


Page 1 of 1




Notes:


Drill Rig: CME 45C



Driller: Ramco


Exhibit: A-12


PE

RC

EN

T F

INE

S

WA

TE

RC

ON

TE

NT

(%

)

ATTERBERGLIMITS

LL-PL-PI

SA

MP

LE T

YP

E

WA

TE

R L

EV

EL

OB

SE

RV

AT

ION

S

DE

PT

H (

Ft.)

5

10

15

20

FIE

LD T

ES

TR

ES

ULT

S

DEPTH





85

16

20

25

35

36

26

8

9

48-19-29

86-27-59

3-8-7N=15

5-7-12N=19

5-7-8N=15

6-8-15N=23

5-12-15N=27

13-23-16N=39

50/5"N=Ref/5"

4.0

9.0

17.0

20.0

FILL: FAT CLAY (CH)brown, very stiff, gravelly

FAT CLAY (CH)dark brown, very stiff

LEAN CLAY (CL)brown to reddish brown, very stiff to hard

- gravelly below 13 feet

WEATHERED LIMESTONEtan, hard, marly



GR

AP

HIC

LO

G

TH

IS B

OR

ING

LO

G IS

NO

T V

ALI

D IF

SE

PA

RA

TE

D F

RO

M O

RIG

INA

L R

EP

OR

T.

G

EO

SM

AR

T L

OG

-NO

WE

LL 9

016

506

8.G

PJ


Page 1 of 1




Notes:


Drill Rig: CME 45C



Driller: Ramco


Exhibit: A-13


PE

RC

EN

T F

INE

S

WA

TE

RC

ON

TE

NT

(%

)

ATTERBERGLIMITS

LL-PL-PI

SA

MP

LE T

YP

E

WA

TE

R L

EV

EL

OB

SE

RV

AT

ION

S

DE

PT

H (

Ft.)

5

10

15

20

FIE

LD T

ES

TR

ES

ULT

S

DEPTH





34

11

12

33

12

12

4

4

23-15-8

47-19-28

3-10-8N=18

3-4-1N=5

4-7-13N=20

9-15-15N=30

12-50/2"N=50/2"

50/1"N=Ref/1"

50/1"N=Ref/1"

4.0

6.0

12.0

20.0

FILL: LEAN CLAY (CH)brown, medium stiff to very stiff

- clayey gravel between 2 to 4 feet


LEAN CLAY (CL)reddish brown, hard with gravel




GR

AP

HIC

LO

G

TH

IS B

OR

ING

LO

G IS

NO

T V

ALI

D IF

SE

PA

RA

TE

D F

RO

M O

RIG

INA

L R

EP

OR

T.

G

EO

SM

AR

T L

OG

-NO

WE

LL 9

016

506

8.G

PJ


Page 1 of 1




Notes:


Drill Rig: CME 45C



Driller: Ramco


Exhibit: A-14


PE

RC

EN

T F

INE

S

WA

TE

RC

ON

TE

NT

(%

)

ATTERBERGLIMITS

LL-PL-PI

SA

MP

LE T

YP

E

WA

TE

R L

EV

EL

OB

SE

RV

AT

ION

S

DE

PT

H (

Ft.)

5

10

15

20

FIE

LD T

ES

TR

ES

ULT

S

DEPTH




29

13

11

12

28

18

7

9

21-17-4

51-22-29

4-7-14N=21

18-15-19N=34

8-9-5N=14

8-14-13N=27

6-13-16N=29

17-20-30N=50

22-37-40N=77

6.0

12.0

20.0

FILL: LEAN CLAY (CH)brown, stiff to hard, gravelly






GR

AP

HIC

LO

G

TH

IS B

OR

ING

LO

G IS

NO

T V

ALI

D IF

SE

PA

RA

TE

D F

RO

M O

RIG

INA

L R

EP

OR

T.

G

EO

SM

AR

T L

OG

-NO

WE

LL 9

016

506

8.G

PJ


Page 1 of 1




Notes:


Drill Rig: CME 45C



Driller: Ramco


Exhibit: A-15


PE

RC

EN

T F

INE

S

WA

TE

RC

ON

TE

NT

(%

)

ATTERBERGLIMITS

LL-PL-PI

SA

MP

LE T

YP

E

WA

TE

R L

EV

EL

OB

SE

RV

AT

ION

S

DE

PT

H (

Ft.)

5

10

15

20

FIE

LD T

ES

TR

ES

ULT

S

DEPTH





23

43

4

10

16

15

12

4

6

19-15-4

13-35-13N=48

13-21-26N=47

8-6-8N=14

6-8-11N=19

50/3"N=Ref/3"

50/3"N=Ref/3"

50/1"N=Ref/1"

6.0

13.0

20.0

FILL: LEAN CLAY (CH)brown to light brown, hard, gravelly

CLAYEY GRAVEL (GC)brown to reddish brown, medium dense to very dense




GR

AP

HIC

LO

G

TH

IS B

OR

ING

LO

G IS

NO

T V

ALI

D IF

SE

PA

RA

TE

D F

RO

M O

RIG

INA

L R

EP

OR

T.

G

EO

SM

AR

T L

OG

-NO

WE

LL 9

016

506

8.G

PJ


Page 1 of 1




Notes:


Drill Rig: CME 45C



Driller: Ramco


Exhibit: A-16


PE

RC

EN

T F

INE

S

WA

TE

RC

ON

TE

NT

(%

)

ATTERBERGLIMITS

LL-PL-PI

SA

MP

LE T

YP

E

WA

TE

R L

EV

EL

OB

SE

RV

AT

ION

S

DE

PT

H (

Ft.)

5

10

15

20

FIE

LD T

ES

TR

ES

ULT

S

DEPTH





49

42

9

13

12

14

12

4

9

28-19-9

23-15-8

15-16-18N=34

20-16-16N=32

19-10-8N=18

9-14-20N=34

21-9-11N=20

50/3"N=Ref/3"

50/3"N=Ref/3"

6.0

12.0

20.0

FILL: LEAN CLAY (CL)dark brown, medium stiff to very stiff, sandy with gravel


- layer of lean clay between 8 and 11 feet




GR

AP

HIC

LO

G

TH

IS B

OR

ING

LO

G IS

NO

T V

ALI

D IF

SE

PA

RA

TE

D F

RO

M O

RIG

INA

L R

EP

OR

T.

G

EO

SM

AR

T L

OG

-NO

WE

LL 9

016

506

8.G

PJ


Page 1 of 1




Notes:


Drill Rig: CME 45C



Driller: Ramco


Exhibit: A-17


PE

RC

EN

T F

INE

S

WA

TE

RC

ON

TE

NT

(%

)

ATTERBERGLIMITS

LL-PL-PI

SA

MP

LE T

YP

E

WA

TE

R L

EV

EL

OB

SE

RV

AT

ION

S

DE

PT

H (

Ft.)

5

10

15

20

FIE

LD T

ES

TR

ES

ULT

S

DEPTH





22

16

11

11

4

4

4

6

11

65-23-42

7-5-9N=14

20-26-16N=42

18-50/6"N=50/6"

50/5"N=Ref/5"

50/6"N=Ref/6"

50/3"N=Ref/3"

50/2"N=Ref/2"

50/0"N=Ref/0"

4.0

7.0

25.0

FILL: FAT CLAY (CH)dark brown, medium stiff to hard with rock





GR

AP

HIC

LO

G

TH

IS B

OR

ING

LO

G IS

NO

T V

ALI

D IF

SE

PA

RA

TE

D F

RO

M O

RIG

INA

L R

EP

OR

T.

G

EO

SM

AR

T L

OG

-NO

WE

LL 9

016

506

8.G

PJ


Page 1 of 1




Notes:


Drill Rig: CME 45C



Driller: Ramco


Exhibit: A-18


PE

RC

EN

T F

INE

S

WA

TE

RC

ON

TE

NT

(%

)

ATTERBERGLIMITS

LL-PL-PI

SA

MP

LE T

YP

E

WA

TE

R L

EV

EL

OB

SE

RV

AT

ION

S

DE

PT

H (

Ft.)

5

10

15

20

25

FIE

LD T

ES

TR

ES

ULT

S

DEPTH




N=Ref/2" sampler could only be driven 2 inch of the 6 inchseating penetration before the 50 blow limit was reached

57

19

16

16

8

7

3

4

7

8

8

43-21-22

33-19-14

11-7-4N=11

25-50/5"N=50/5"

50/2"N=Ref/2"

30-37-39N=76

31-50/5"N=50/5"

50/0"N=Ref/0"

50/0"N=Ref/0"

50/0"N=Ref/0"

2.0

11.0

25.0

FILL: LEAN CLAY (CL)dark brown, stiff, sandy with gravel



- turns to gray below 18 feet



GR

AP

HIC

LO

G

TH

IS B

OR

ING

LO

G IS

NO

T V

ALI

D IF

SE

PA

RA

TE

D F

RO

M O

RIG

INA

L R

EP

OR

T.

G

EO

SM

AR

T L

OG

-NO

WE

LL 9

016

506

8.G

PJ


Page 1 of 1




Notes:


Drill Rig: CME 45C



Driller: Ramco


Exhibit: A-19


PE

RC

EN

T F

INE

S

WA

TE

RC

ON

TE

NT

(%

)

ATTERBERGLIMITS

LL-PL-PI

SA

MP

LE T

YP

E

WA

TE

R L

EV

EL

OB

SE

RV

AT

ION

S

DE

PT

H (

Ft.)

5

10

15

20

25

FIE

LD T

ES

TR

ES

ULT

S

DEPTH




N=Ref/3" sampler could only be driven 3 inch of the 6 inchseating penetration before the 50 blow limit was reached

88

20

9

33

18

7

8

8

8

6

82-35-47

NP

8-7-10N=17

6-6-5N=11

6-11-15N=26

26-19-25N=44

21-15-9N=24

50/2"N=Ref/2"

19-50/2"N=50/2"

50/3"N=Ref/3"

6.0

12.0

25.0

FILL: FAT CLAY (CH)dark brown, stiff to very stiff, gravelly at the surface





GR

AP

HIC

LO

G

TH

IS B

OR

ING

LO

G IS

NO

T V

ALI

D IF

SE

PA

RA

TE

D F

RO

M O

RIG

INA

L R

EP

OR

T.

G

EO

SM

AR

T L

OG

-NO

WE

LL 9

016

506

8.G

PJ


Page 1 of 1




Notes:


Drill Rig: CME 45C



Driller: Ramco


Exhibit: A-20


PE

RC

EN

T F

INE

S

WA

TE

RC

ON

TE

NT

(%

)

ATTERBERGLIMITS

LL-PL-PI

SA

MP

LE T

YP

E

WA

TE

R L

EV

EL

OB

SE

RV

AT

ION

S

DE

PT

H (

Ft.)

5

10

15

20

25

FIE

LD T

ES

TR

ES

ULT

S

DEPTH





53

31

13

16

13

17

8

8

8

33-21-12

53-25-28

4-3-4N=7

8-12-10N=22

4-3-3N=6

8-12-12N=24

47-50/1"N=50/1"

50/2"N=Ref/2"

50/2"N=Ref/2"

50/0"N=Ref/0"

6.0

8.0

13.0

25.0

FILL: LEAN CLAY (CL)dark brown, medium stiff to very stiff, gravelly

FAT CLAY (CH)brown, very stiff





GR

AP

HIC

LO

G

TH

IS B

OR

ING

LO

G IS

NO

T V

ALI

D IF

SE

PA

RA

TE

D F

RO

M O

RIG

INA

L R

EP

OR

T.

G

EO

SM

AR

T L

OG

-NO

WE

LL 9

016

506

8.G

PJ


Page 1 of 1




Notes:


Drill Rig: CME 45C



Driller: Ramco


Exhibit: A-21


PE

RC

EN

T F

INE

S

WA

TE

RC

ON

TE

NT

(%

)

ATTERBERGLIMITS

LL-PL-PI

SA

MP

LE T

YP

E

WA

TE

R L

EV

EL

OB

SE

RV

AT

ION

S

DE

PT

H (

Ft.)

5

10

15

20

25

FIE

LD T

ES

TR

ES

ULT

S

DEPTH





34

24

20

10

11

7

4

11

59-26-33

28-16-12

28-14-14

4-5-4N=9

6-22-26N=48

8-12-25N=37

30-50/5"N=50/5"

31-29-38N=67

50/4"N=Ref/4"

3.0

12.0

15.0

FILL: CLAYEY GRAVEL (GC)dark brown, loose

CLAYEY GRAVEL (GC)reddish brown, dense to very dense




GR

AP

HIC

LO

G

TH

IS B

OR

ING

LO

G IS

NO

T V

ALI

D IF

SE

PA

RA

TE

D F

RO

M O

RIG

INA

L R

EP

OR

T.

G

EO

SM

AR

T L

OG

-NO

WE

LL 9

016

506

8.G

PJ


Page 1 of 1




Notes:


Drill Rig: CME 45C



Driller: Ramco


Exhibit: A-22


PE

RC

EN

T F

INE

S

WA

TE

RC

ON

TE

NT

(%

)

ATTERBERGLIMITS

LL-PL-PI

SA

MP

LE T

YP

E

WA

TE

R L

EV

EL

OB

SE

RV

AT

ION

S

DE

PT

H (

Ft.)

5

10

15

FIE

LD T

ES

TR

ES

ULT

S

DEPTH





42

20

10

8

21

9

7

8

9

30-15-15

23-16-7

8-17-15N=32

8-8-8N=16

11-20-9N=29

16-21-32N=53

35-39-27N=66

9-50/2"N=50/2"

50/4"N=Ref/4"

4.0

16.0

20.0

FILL: LEAN CLAY (CL)dark brown, very stiff to hard, gravelly

CLAYEY GRAVEL (GC)brown, medium dense to very dense




GR

AP

HIC

LO

G

TH

IS B

OR

ING

LO

G IS

NO

T V

ALI

D IF

SE

PA

RA

TE

D F

RO

M O

RIG

INA

L R

EP

OR

T.

G

EO

SM

AR

T L

OG

-NO

WE

LL 9

016

506

8.G

PJ


Page 1 of 1




Notes:


Drill Rig: CME 45C



Driller: Ramco


Exhibit: A-23


PE

RC

EN

T F

INE

S

WA

TE

RC

ON

TE

NT

(%

)

ATTERBERGLIMITS

LL-PL-PI

SA

MP

LE T

YP

E

WA

TE

R L

EV

EL

OB

SE

RV

AT

ION

S

DE

PT

H (

Ft.)

5

10

15

20

FIE

LD T

ES

TR

ES

ULT

S

DEPTH




4.0

5.0

6.0

FILL - CLAYEY GRAVEL WITH SAND (GC)light brown and brown, with boulders

FILL - FAT CLAY (CH)dark brown, with gravel

CLAYEY GRAVEL WITH SAND (GC)reddish brown

Test Pit Terminated at 6 Feet

Stratification lines are approximate. In-situ, the transition may be gradual.

GR

AP

HIC

LO

G

TH

IS B

OR

ING

LO

G IS

NO

T V

ALI

D IF

SE

PA

RA

TE

D F

RO

M O

RIG

INA

L R

EP

OR

T.

GE

O S

MA

RT

LO

G-N

O W

ELL

901

552

70.G

PJ

Talavera Ridge & Old Camp Bullis Road San Antonio, TexasSITE:

Page 1 of 1

Advancement Method:

Abandonment Method:Backfilled with on-site soil

6911 Blanco RoadSan Antonio, Texas

Notes:


Excavator: backhoe

Test Pit Started: 12/9/2016

TEST PIT LOG NO. TP-1Oden Hughes Multifamily Development &CLIENT:Construction

Operator:

Test Pit Completed: 12/9/2016

Exhibit: A-24

Austin, Texas

PROJECT: Amara Apartments

PE

RC

EN

T F

INE

S

WA

TE

RC

ON

TE

NT

(%

)

ATTERBERGLIMITS

LL-PL-PI

SA

MP

LE T

YP

E

WA

TE

R L

EV

EL

OB

SE

RV

AT

ION

S

DE

PT

H (

Ft.)

5

FIE

LD T

ES

TR

ES

ULT

S

DEPTH



WATER LEVEL OBSERVATIONS

5.0

6.0

FILL -FAT CLAY (CH)dark brown brown and brown, with cobbles, boulders, wood, and metal debris




GR

AP

HIC

LO

G

TH

IS B

OR

ING

LO

G IS

NO

T V

ALI

D IF

SE

PA

RA

TE

D F

RO

M O

RIG

INA

L R

EP

OR

T.

GE

O S

MA

RT

LO

G-N

O W

ELL

901

552

70.G

PJ


Page 1 of 1

Advancement Method:



Notes:


Excavator: backhoe



Operator:


Exhibit: A-25

Austin, Texas


PE

RC

EN

T F

INE

S

WA

TE

RC

ON

TE

NT

(%

)

ATTERBERGLIMITS

LL-PL-PI

SA

MP

LE T

YP

E

WA

TE

R L

EV

EL

OB

SE

RV

AT

ION

S

DE

PT

H (

Ft.)

5

FIE

LD T

ES

TR

ES

ULT

S

DEPTH




6.0

7.0

FILL - CLAYEY GRAVEL WITH SAND (GC)light brown, with boulders




GR

AP

HIC

LO

G

TH

IS B

OR

ING

LO

G IS

NO

T V

ALI

D IF

SE

PA

RA

TE

D F

RO

M O

RIG

INA

L R

EP

OR

T.

GE

O S

MA

RT

LO

G-N

O W

ELL

901

552

70.G

PJ


Page 1 of 1

Advancement Method:



Notes:


Excavator: backhoe



Operator:


Exhibit: A-26

Austin, Texas


PE

RC

EN

T F

INE

S

WA

TE

RC

ON

TE

NT

(%

)

ATTERBERGLIMITS

LL-PL-PI

SA

MP

LE T

YP

E

WA

TE

R L

EV

EL

OB

SE

RV

AT

ION

S

DE

PT

H (

Ft.)

5

FIE

LD T

ES

TR

ES

ULT

S

DEPTH




APPENDIX B




Reliable ■ Resourceful ■ Responsive Exhibit B-1

Laboratory Testing

Samples retrieved during the field exploration were taken to the laboratory for further observation

by the project geotechnical engineer and were classified in accordance with the Unified Soil

Classification System (USCS) described in this Appendix. At that time, the field descriptions were

confirmed or modified as necessary and an applicable laboratory testing program was formulated

to determine engineering properties of the subsurface materials.

Laboratory tests were conducted on selected soil samples and the test results are presented in

this appendix. The laboratory test results were used for the geotechnical engineering analyses,

and the development of foundation and earthwork recommendations. Laboratory tests were

performed in general accordance with the applicable ASTM, local or other accepted standards.

Selected soil samples obtained from the site were tested for the following engineering properties:

Moisture Content

Atterberg Limits

Percent Passing the No. 200 Sieve

Sample Disposal

All samples were returned to our laboratory. The samples not tested in the laboratory will be

stored for a period of 30 days subsequent to submittal of this report and will be discarded after

this period, unless other arrangements are made prior to the disposal period.

APPENDIX C

PLASTICITY DESCRIPTION

Term

< 1515 - 29> 30

Descriptive Term(s)of other constituents

Water InitiallyEncountered

Water Level After aSpecified Period of Time

Major Componentof Sample

Percent ofDry Weight

(More than 50% retained on No. 200 sieve.)Density determined by Standard Penetration Resistance

Includes gravels, sands and silts.

Hard

Unconfined CompressiveStrength, Qu, tsf

Very Loose 0 - 3 0 - 6 Very Soft less than 0.25

7 - 18 Soft 0.25 to 0.50

10 - 29 19 - 58 0.50 to 1.00

59 - 98 Stiff 1.00 to 2.00

> 99 2.00 to 4.00

LOCATION AND ELEVATION NOTES

SA

MP

LIN

G

FIE

LD

TE

ST

S

(HP)

(T)

(b/f)

(PID)

(OVA)

DESCRIPTION OF SYMBOLS AND ABBREVIATIONS

Descriptive Term(Density)

Non-plasticLowMediumHigh

BouldersCobblesGravelSandSilt or Clay

10 - 18

> 50 15 - 30 19 - 42

> 30 > 42

_

Hand Penetrometer

Torvane

Standard PenetrationTest (blows per foot)

Photo-Ionization Detector

Organic Vapor Analyzer

Water levels indicated on the soil boringlogs are the levels measured in theborehole at the times indicated.Groundwater level variations will occurover time. In low permeability soils,accurate determination of groundwaterlevels is not possible with short termwater level observations.

CONSISTENCY OF FINE-GRAINED SOILS

(50% or more passing the No. 200 sieve.)Consistency determined by laboratory shear strength testing, field

visual-manual procedures or standard penetration resistance

DESCRIPTIVE SOIL CLASSIFICATION

Unless otherwise noted, Latitude and Longitude are approximately determined using a hand-held GPS device. The accuracyof such devices is variable. Surface elevation data annotated with +/- indicates that no actual topographical survey wasconducted to confirm the surface elevation. Instead, the surface elevation was approximately determined from topographicmaps of the area.

Soil classification is based on the Unified Soil Classification System. Coarse Grained Soils have more than 50% of their dryweight retained on a #200 sieve; their principal descriptors are: boulders, cobbles, gravel or sand. Fine Grained Soils haveless than 50% of their dry weight retained on a #200 sieve; they are principally described as clays if they are plastic, andsilts if they are slightly plastic or non-plastic. Major constituents may be added as modifiers and minor constituents may beadded according to the relative proportions based on grain size. In addition to gradation, coarse-grained soils are definedon the basis of their in-place relative density and fine-grained soils on the basis of their consistency.

Plasticity Index

01 - 1011 - 30

> 30

RELATIVE PROPORTIONS OF FINES

Descriptive Term(s)of other constituents

Percent ofDry Weight

< 55 - 12> 12

TraceWithModifier

Water Level Aftera Specified Period of Time

GRAIN SIZE TERMINOLOGYRELATIVE PROPORTIONS OF SAND AND GRAVEL

TraceWithModifier

Standard Penetration orN-Value

Blows/Ft.

Descriptive Term(Consistency)

Loose

Very Stiff

Standard Penetration orN-Value

Blows/Ft.

Ring SamplerBlows/Ft.

Ring SamplerBlows/Ft.

Medium Dense

Dense

Very Dense

0 - 1 < 3

4 - 9 2 - 4 3 - 4

Medium-Stiff

8 - 15

Exhibit C-1

5 - 9

30 - 50

WA

TE

R L

EV

EL

Auger

Shelby Tube

Ring Sampler

Grab Sample

Split Spoon

Macro Core

Rock Core

No Recovery

RELATIVE DENSITY OF COARSE-GRAINED SOILS

Particle Size

Over 12 in. (300 mm)12 in. to 3 in. (300mm to 75mm)3 in. to #4 sieve (75mm to 4.75 mm)#4 to #200 sieve (4.75mm to 0.075mmPassing #200 sieve (0.075mm)

ST

RE

NG

TH

TE

RM

S

> 4.00

4 - 8

GENERAL NOTES

Exhibit C-2

UNIFIED SOIL CLASSIFICATION SYSTEM

Criteria for Assigning Group Symbols and Group Names Using Laboratory Tests A

Soil Classification

Group

Symbol Group Name

B

Coarse Grained Soils:

More than 50% retained

on No. 200 sieve

Gravels:

More than 50% of

coarse fraction retained

on No. 4 sieve

Clean Gravels:

Less than 5% fines C

Cu 4 and 1 Cc 3 E

GW Well-graded gravel F

Cu 4 and/or 1 Cc 3 E

GP Poorly graded gravel F

Gravels with Fines:

More than 12% fines C

Fines classify as ML or MH GM Silty gravel F,G,H

Fines classify as CL or CH GC Clayey gravel F,G,H

Sands:

50% or more of coarse

fraction passes No. 4

sieve

Clean Sands:

Less than 5% fines D

Cu 6 and 1 Cc 3 E

SW Well-graded sand I

Cu 6 and/or 1 Cc 3 E

SP Poorly graded sand I

Sands with Fines:

More than 12% fines D

Fines classify as ML or MH SM Silty sand G,H,I

Fines classify as CL or CH SC Clayey sand G,H,I

Fine-Grained Soils:

50% or more passes the

No. 200 sieve

Silts and Clays:

Liquid limit less than 50

Inorganic: PI 7 and plots on or above “A” line

J CL Lean clay

K,L,M

PI 4 or plots below “A” line J ML Silt

K,L,M

Organic: Liquid limit - oven dried

0.75 OL Organic clay

K,L,M,N

Liquid limit - not dried Organic silt K,L,M,O

Silts and Clays:

Liquid limit 50 or more

Inorganic: PI plots on or above “A” line CH Fat clay

K,L,M

PI plots below “A” line MH Elastic Silt K,L,M

Organic: Liquid limit - oven dried

0.75 OH Organic clay

K,L,M,P

Liquid limit - not dried Organic silt K,L,M,Q

Highly organic soils: Primarily organic matter, dark in color, and organic odor PT Peat

A Based on the material passing the 3-inch (75-mm) sieve

B If field sample contained cobbles or boulders, or both, add “with cobbles

or boulders, or both” to group name. C

Gravels with 5 to 12% fines require dual symbols: GW-GM well-graded

gravel with silt, GW-GC well-graded gravel with clay, GP-GM poorly

graded gravel with silt, GP-GC poorly graded gravel with clay. D

Sands with 5 to 12% fines require dual symbols: SW-SM well-graded

sand with silt, SW-SC well-graded sand with clay, SP-SM poorly graded

sand with silt, SP-SC poorly graded sand with clay

E Cu = D60/D10 Cc =

6010

2

30

DxD

)(D

F If soil contains 15% sand, add “with sand” to group name.

G If fines classify as CL-ML, use dual symbol GC-GM, or SC-SM.

H If fines are organic, add “with organic fines” to group name.

I If soil contains 15% gravel, add “with gravel” to group name.

J If Atterberg limits plot in shaded area, soil is a CL-ML, silty clay.

K If soil contains 15 to 29% plus No. 200, add “with sand” or “with gravel,”

whichever is predominant. L

If soil contains 30% plus No. 200 predominantly sand, add “sandy” to

group name. M

If soil contains 30% plus No. 200, predominantly gravel, add

“gravelly” to group name. N

PI 4 and plots on or above “A” line. O

PI 4 or plots below “A” line. P

PI plots on or above “A” line. Q

PI plots below “A” line.

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