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Continuously Reinforced Concrete Pavement (CRCP) Design and Construction Guide
1.0 PURPOS O! "#$S GU$D
The purpose of this Guide is to provide Caltrans and consultant pavement engineers with a
uniform, streamlined process for designing continuously reinforced concrete pavements onCaltrans-approved projects. The Guide also addresses related topics that the pavement engineer
needs for making effective pavement decisions. As a part of this guide, appropriate figures were
obtained from Concrete einforcing !teel "nstitute #C!"$. eferences used are superscripted in
the document and are listed in !ection %%.
%.0 DSCR$P"$O&
A Continuously einforced Concrete &avement #CC&$ is one type of rigid pavement, also
referred to as &ortland Cement Concrete &avement #&CC&$ with reinforcing steel and no
transverse joints. CC&s are reinforced in the longitudinal direction, and additional steel is also
used in the transverse direction to hold the longitudinal steel in place #see 'igure %$. The
longitudinal bars are lap spliced so that continuity of the steel is maintained, ensuring good
performance of the pavement #see !ection (.).% for this topic$. *ue to the continuous
reinforcement in the longitudinal direction, the pavement develops transverse cracks spaced at
close intervals. These cracks develop due to changes in the concrete volume, restrained by the
longitudinal reinforcement steel, resulting from moisture and temperature variation. Crack width
can affect the rate of corrosion of the reinforcing steel at the crack locations when water or de-
icing salts #if used$ penetrate the cracks. "n a well-designed CC&, the longitudinal steel should
be able to keep the transverse cracks tightly closed and minimi+e water penetration.
'igure % CC& ongitudinal and Transverse einforcements
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The optimum amount of longitudinal reinforcement steel in the standard plans is determined
such that it satisfies all of the following three limiting criteria
Cracks spacing "n order to minimi+e the potential of concrete punch out and spalling, the
spacing between consecutive cracks must be limited between ./ ft. #to limit punch out$ and 0.1
ft. #to limit spalling$
Cracks width "n order to minimi+e spalling, water infiltration and load transfer, the allowable
crack width should not e2ceed 1.1( in.
!teel stress "n order to prevent steel yielding and e2cessive permanent deformation, the tensile
stress in steel is limited to no more than 3/4 of its ultimate tensile strength.
'.0 &!$"S &D PP*$C"$O&S
A number of benefits could be gained from using CC& for the construction of highways. They
include
5ess maintenance re6uired, thus reducing the need for future maintenance closure.
5ower maintenance cost because there are no transverse joints to maintain.
5educed water penetration because there are fewer joints and tighter transverse cracks.
5!moother pavements over time since there are no transverse joints.
5ower long-term life cycle cost despite potential higher initial cost.
5Ability to handle heavier truck loading and volumes. There are situations, however, whereCC& may not be desirable
5'or conventional highways, local roads, and areas where there are utilities underneath the
roadbed. Accessing #digging up$ to maintain these utilities can damage the CC&.
5'or parking areas since CC& is e2pensive to build for lightly trafficked locations The
*epartment7s policy is to use CC& for rigid pavements where it is determined to be cost-
efective. ife cycle cost analysis #CCA$ is the most effective means to help make such
determination. The *epartment7s &avement website at
http88www.dot.ca.gov8h68esc8 Translab89&*8*ivisionof*esign-&avement-&rogram.htm
provides information on performing CCA.
(.1 C9:&9;<;T! 9' CC&
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A typical CC& is constructed of concrete, steel bars, and joints. "n the following, a brief
discussion of each of these components will be presented along with necessary aspects for their
design.
(.% Concrete
Concrete is an artificial stone-like material used for various structural purposes. "t is made by
mi2ing cement, sand, and various aggregates such as pebbles, gravel, and shale, with water and
allowing the mi2ture to harden by hydration. Cement in concrete acts as a primary binder to join
the aggregates into a solid mass. ike =ointed &lain Concrete &avement #=&C&$, CC& is
constructed using &ortland Cement Concrete #&CC$ e2cept that aggregates used must have
coefficient of thermal e2pansion of >.1 2 %1-> 8 ' or less. !ection (1 of the !tandard
!pecification covers general concept in &CC pavement construction,
!ection ?1-% of the !tandard !pecification covers the types, classes, and strength of &CC@ and
!ection ?1-) covers the specified materials necessary to produce the &CC.
.
(.) !teel
CC& contains both longitudinal and transverse steel. *eformed steel bars used are those that
meet the re6uirements set out in
!ection /) einforcement in the !tandard !pecifications. The use of epo2y-coated reinforcing
bar is not necessary for CC& , e2cept in areas where corrosion is known to be a problem #e.g.,
because of the presence of salts or the application of de-icing salts$. "n California, epo2y coating
should be used in high desert and all mountain climate regions #!ee California climate map on
the &avement website at
http88www.dot.ca.gov8h68oppd8pavement8&avementClimateregions%11/1/.pdf $, and when the
project is within half a mile distance from a salt-water body. "n the following, both longitudinal
and transverse steel as well as steel tie bars are discussed.
(.).% ongitudinal einforcement
The function of the longitudinal steel is to strengthen the concrete, to control concrete volumetric
changes due to temperature and moisture variations, and to keep transverse cracks tightly closed.
"f the steel is able both to serve its function #i.e., reinforcement$ and to keep cracks fromwidening, the aggregate interlock #i.e., the mechanical locking that forms between the fractured
surfaces of concrete along any transverse crack$ will be preserved and stresses in the concrete
due to traffic loading will be reduced. ongitudinal reinforcement steel used for CC& consists
of Grade >1 ;o. > steel bars, spaced at/./ to ?.1 inches center-to-center. The recommended
position of the longitudinal steel is (.1inches from the surface of the concrete to the top of
reinforcement bars #see !tandard &lan &($ e2cept for thicknesses greater than .?/-foot where
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slightly deeper cover is needed so that the transverse bar is not cut by the joint saw. :aintaining
steel continuity in the longitudinal direction in CC& ensures good performance of the
pavement. The continuity of the steel is achieved by overlapping each steel bar. A staggered
splice pattern as shown in the schematic drawing in 'igure ) is recommended for splicing
longitudinal steel. A minimum lap length of (/ diameters of the smaller bar joined #( Binches
for > longitudinal bar$, and a minimum clear distance between staggers should be the same as
the length re6uired for a lap splice of the largest bar
. e6uirement for reinforcement splicing can be found in !ection /)-%.10 in the !tandard
!pecification
. Additional longitudinal reinforcement is placed at transverse contact #construction$ joint to
ensure sufficient reinforcement at points of discontinuity #see !ection (. on this and other types
of joint used in CC&$.
'ig ) !taggered ap splice
(.).) Transverse !teel
Transverse steel is used across the entire width of CC& lanes primarily to support the
longitudinal reinforcements during construction, and to tighten and reduce the risk of occurring
and opening-up of random longitudinal cracks, thus reducing the potential of punch outs.
ongitudinal cracks occur appro2imately parallel to the centerline of the pavement. Additionally,
transverse steel is used to tie adjacent lanes together across weakened plane joints #see !ection
(. for this type of joint$.Transverse steel is usually Grade >1 ;o. > deformed steel bars spaced
at %).1 to >.1 inches center-to-center depending on the pavement width.
(.). Tie Dars
Tie bars are deformed /1-inch long, epo2y-coated Grade >1 ;o. > steel bars, placed in the same
plane as transverse reinforcement and perpendicular to the longitudinal joint to hold the faces of
abutting concrete in contact, and to help develop interlock along these joints. Tie bars are
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typically used at longitudinal contact joints or between an edge joint and shoulder. The spacing
of the tie bars is the same as that used for the transverse reinforcement bars. The common
method of tie bar placement is with a mechanical splice, as shown in !tandard &lan&(. The
*epartment does not allow the use of bent tie bars even though they could be straightened after
placement of the concrete. This is because bending of tie bars causes them to lose their epo2y
coating and in some cases causes the tie bars to break. "t also causes the concrete to crack
because of its brittleness.
+.' ,oints
=oints are vital to control cracking and hori+ontal movements of the pavement. &lain concrete
pavements without joints would be riddled with cracks within one or two years after placement.
<ven with =&C&s, incorrectly placed or poorly designed joints will result in premature
pavementcracking. CC&s do not contain transverse weakened plane joints like their =&C&
counterparts. Eowever, joints in CC& include transverse contact joints #also known as
construction joints$, longitudinal contact joints, longitudinal weakened plane joints, and terminal joints. The !tandard &lans should be consulted for the proper depth, width, line of the saw cut
and type of seal re6uired to construct these joints. "n the following, the various types of joints
commonly used in CC&s are discussed.
+.'.1 "ransverse Contact ,oints
A contact joint #see 'igure $ is a joint formed when #i$ concrete is placed at different times, or
#ii$ when paving is interrupted at the end of each day7s paving operation, or #iii$ the paving is
interrupted for more than 1 minutes. An additional ()-inch long longitudinal reinforcement is
placed in the transverse contact joint on the same plane and twice the distance as the longitudinalreinforcements
'igure A Transverse Contact =oint 'ormed
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Transverse contact joint should be planned so that they coincide whenever possible with terminal
joints #see !ection (..( for this type of joint$ to eliminate e2tra joints.
+.'.% *ongitudinal ,oints
ongitudinal joints #see 'igure ($ are necessary to control cracking in the longitudinal directiondue to warping, e2pansion and shrinkage stresses caused by temperature variations when
concrete is placed in great widths. They are constructed at lane lines, typically in multiples of
%)feet. Fhere there are no lanes, longitudinal joints should be spaced %) feet apart, but no more
than %( feet apart. Fhen widened slabs are used, longitudinal joints are omitted at the edge of
traveled way.
'igure ( ongitudinal Contact =oint at ane ine
(..).% Contact =oints
=oints between separately placed adjoining lanes are longitudinal contact joints. Tie bars #see
!ection (.).$ are used to tie the adjoining concrete placement together.
(..).) Feakened &lane =oints
A longitudinal weakened plane #contraction$ joint is formed by saw-cutting concrete to a depth
specified in the specification at lane lines or other locations specified on the plans. Feakened
plane joints are held together by transverse steel reinforcement.
(.. Terminal =oints
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A terminal joint is used in CC& to transition to another pavement type of differing design, or to
a bridge structure, or to limit hori+ontal movement. Their function is primarily to #i$ isolate
adjacent pavement types or structures, and #ii$ anchor the CC& so that e2cessive hori+ontal
movement does not occur that would otherwise damage the CC& and the adjacent pavement or
structure. Terminal joints are provided and located at the beginning and end sections of CC&
used to accommodate longitudinal movement due to shrinkage or swelling caused by thermal
variations so as to protect the abutting ends of CC& and other pavements. Table % lists the types
of terminal joints and where they can be used. The various types of these joints are discussed
briefly in the following sections.
Table %. Fide 'lange Deam Terminal =oint (
Terminal =oint Types =oint Type Fhere to se it
Fide 'lange Deam Terminal =oint se at all bridge approaches, transition
between CC& other rigid pavements, and
fle2ible pavements at grade of (4 or greater.
Can use for any transition.
Terminal and =oint-Type A se for any locations where CC& abuts to
e2isting fle2ible pavement.
Terminal =oint-Type D se for any locations where CC&
construction is terminated at a planned
location.
Terminal =oint-Type C se for any locations where CC& abuts to
new or temporary fle2ible pavement.
(...% Fide 'lange Deam Terminal =oint
The wide flange beam terminal joint #see 'igure /$ has been a standard practice used by many
highway agencies to accommodate pavement end movements. The si+e of the wide flange beam
is dependent on pavement thickness and truck traffic volume. Fithin the limits of wide flange
pavement terminal installation, the subgrade should be prepared and compacted as specified in
the special provisions in the same manner as the rest of the roadbed before additional layers of
subbase and base are put on top of the subgrade
Fhere e2pansive soil is encountered, !ection>%(.( of the Caltrans E*: should be consulted in
order to address this type of soil.
The wide flange beam is set partially into %1-foot long and %)-inch minimum thick sleeper slab,
which provides support for the CC& and concrete pavement abutting at each end. "n order to
achieve long-term performance without significant repair, the design of the wide flange beam
should consider #i$ allowable end movements of pavement, #ii$ load transfer across the joint, #iii$
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the durability of the wide flange beam to resist corrosion effects, #iv$ fatigue loading under heavy
truck traffic, and #v$ rigid connection to bridge side pavement . These design considerations are
e2plained below. !ince wide flange beam accommodates end movement, an e2pansion joint is
usually needed #i$ at the bridge approach slab, or #ii$ between the wide flange beam and
pavement end transition. Fide flange beam is susceptible to corrosion if placed in an
environment near salt-water body or where there is an e2tensive use of de-icing salts. The use of
galvani+ed beam is necessary to protect the beam from corrosion. As an alternative to galvani+ed
beam, either epo2y coating or a wider or thicker flange beam may be considered. The use of
thicker or wider flange can provide for improved resistance to fatigue-related failures under
heavy truck traffic loading. The wide flange beam can fail when the top flange separates from the
beam web. !o that rigid connection can be maintained and premature failure prevented, studs
1.3/-inch in diameter and 0inches long are welded to the flange bottom and the web spaced
alternately at ? inches and anchored to the concrete pavement end on the bridge side of the joint.
This rigid connection can help maintain profile and cross slope at the joints over the service life.
'igure / Fide 'lange Deam Terminal =oint
=oint !tandard &lans &)A and &)D contain the following information for wide flange beams
5ocation of the wide flange terminal joint at bridge approaches and at transition pavements
#rigid or fle2ible$
5Table of beam si+es with respect to pavement thicknesses.
5*owel bar at e2pansion joint.
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• !tud connection to wide flange beam.
5Dar si+es used in tying support slab to CC& at e2pansion joint.
The following information for wide flange terminal joints should be shown in the plans
5 The location of the wide flange terminal joint by station.
5 &avement width, thickness, and crown cross-slope on typical sections.
!tandard &lans &)A and &)D - HContinuously einforced Concrete &avement B Fide 'lange
&avement TerminalI show a wide flange terminal system to accommodate the movement at the
joint between the abutting end of a CC& on one side and end of the bridge, approach slab or
another rigid pavement on the other side. 'igure > shows a schematic drawing of wide flange
beam terminal.
;otes aJ %/ feet minimum at bridge. bJ )1 feet at concrete pavement end transition. cJ)1 feet.
!igure - /ide !lange eam "erminal Details
"n conjunction with wide flange beam terminal joint, the e2pansion joint is provided to
accommodate large e2pansion of pavement e2ceeding 1./1 inch. Fhere e2pansion joint is to
documents. At pavement transition, the e2pansion joint is not used where fle2ible pavement
abuts to CC& or other rigid pavement#see !tandard &lan &1$.
+.'.'.% "ye "ye "ye C "erminal ,oints
Fhere CC& begins or terminates at e2isting fle2ible pavement, Type A terminal joint is used be used, a sleeper slab beneath the joint is constructed to provide a large bearing area and to
serve as a support for the free edges of the abutting concrete pavements. 9ne inch of e2panded
polystyrene is placed over the slab support prior to placing the concrete to prevent bonding and
to allow the pavement to move easily when it contracts and e2pands. The e2pansion joint width
formed between the CC& and a bridge, approach slab, or any other rigid pavement re6uires the
Type D seal #% K :ovement ating$ as shown in !tandard &lan D>-)%. The Type D !eal is
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specified and paid for as a separate item of work in contract. The longitudinal reinforcement is
terminated ) inches from the construction joint where abutting pavements occur. Two transverse
contractions joints are formed by saw cuts made at %1 feet and )/ feet from the construction
joint. Fhere CC& is terminated without adjoining pavement, Type D joint is used. At the
terminal section of CC& a )3-foot long by %1-foot thick slab is provided for end support of the
CC&. The support slab is tied to CC& with Grade >1, ;o. / reinforcement so that good support
is also provided for the future pavement. The end of CC& is backfilled with soil and graded to
%.Fhere CC& terminates at new or temporary fle2ible pavement, terminal Type C joint is
used. At the terminal section of CC& a )3-foot long by %1-foot thick slab is provided for end
support of the CC& and new or temporary fle2ible pavements. The support slab is tied to CC&
with Grade >1, ;o. / reinforcement.
+.+ Pavement nd "ransition
&avement end transitions are made up of different pavement materials constructed within the
same lane. The pavement transitions can be concrete pavement abutting to approach slab or concrete pavement abutting to fle2ible layer pavement. The use of dowel-jointed pavement at
pavement transition eliminates the use of pressure relief or e2pansion joint. Fhen the pavement
transition changes from fle2ible pavement to concrete pavement, the *epartment recommends
are inforced concrete wedge panel at the transition to reduce the damaging effect of impact
loading at the transition #see the evised !tandard &lans !& &1 for different types of pavement
transition$.
2.0 DS$G& O! CRCP
This section provides all information necessary for the pavement engineer to design a CC&.
2.1 Design *ife
Topic >%) of the Caltrans Eighway *esign :anual #E*:$ discusses pavement design life. The
E*: and this Guide recommend that CC& be designed for a design life of (1 years. This life
represents the optimum number of years that a CC& should be e2pected to perform
satisfactorily before reaching its terminal serviceability or reaching a condition that re6uires
major rehabilitation.
2.% Performance !actors
&erformance factors for CC& can be found in Topic >)) of E*:. The performance factors for
a CC& are different from those used with =&C&. Fhereas =&C& performance is primarily based
on cracking and joint faulting, CC& performance is judged by punch outs #see 'igure ($. &er
E*: Topic >)),
CC& is designed to have no more than %1 punch outs per mile at the end of its pavement design
life.
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2.' Design "3ic4nesses
To design a CC&, Topic >) of E*: contains information on the thickness of concrete surface
layer, and the thickness and type of the base and subbase layers. These thicknesses can be used
for new construction, reconstruction, widening, and lane replacement.
2.+ Ot3er Design Considerations
2.+.1 Detailing
A CC& should be accurately detailed on the project typical sections, layouts, and construction
details. The pavement on the project plans and details should be defined as CC& with the limits
shown on the project layouts.
2.+.% S3oulders
Two types of shoulders can be used with CC& tied rigid shoulder or widened traffic lane #see
E*: "nde2 >)/.($.
2.+.%.1 "ied Rigid S3oulder
A rigid shoulder that is tied to the adjacent traffic lane with tie bars provides lateral support to
that lane. "n order to obtain the ma2imum benefit, the rigid shoulder should be built
monolithically with the adjacent lane #i.e., no contact joints$. 'or this reason, the shoulder cross
slope should match the lane cross slope which may re6uire a design e2ception. The structural
section for the tied rigid shoulder should match the structural section of the adjacent traffic lane.
Tied rigid shoulders are the most adaptable and preferred type of shoulders when future
widening is planned within the design life of the pavement, or when the shoulder is to be usedtemporarily as a bus or truck lane. Fhen it is e2pected to be converted into a traffic lane in the
future, tied rigid shoulders should be built to the same geometrics and pavement standards as the
traffic lane.
2.+.%.% /idened *anes
Fidened lanes are concrete panels that are %(-foot wide in place of the prescribed lane width
constructed for the traffic lane adjacent to the rigid or fle2ible shoulder
Dy striping the lane at%) feet, the additional width becomes part of the shoulder width, which
will keep the truck wheel path away from the longitudinal joint. "n addition, it provides lateral
support to fle2ible or rigid shoulder by means of reducing the stresses that can lead to spalling
along the longitudinal joint.
-.0 CO&S"RUC"$O& O! CRCP
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This section provides an overview of the basic steps involved in CC& construction@ namely
base, subbase and subgrade preparation, reinforcing bars placement, concrete placement,
concrete consolidation, finishing, curing and jointing. These basic elements are common to both
fi2ed form and slip form paving.
-.1 Su5grade Su55ase and ase Prearation
&avements constructed without ade6uate subgrade, subbase and base preparation may fail
prematurely because of inade6uate support. Also, pavements constructed without ade6uate base
and subbase preparation may not meet smoothness specifications and long-term pavement
performance.
-.1.1 Su5grade Prearation
The overall strength and performance of a pavement is dependent on many factors including the
load-bearing capacity of the subgrade. Anything that can be done to increase the load-bearing
capacity or structural support of the subgrade soil will most likely improve the overall strength
And performance of the pavement. Generally, greater subgrade structural capacity can result in
more economical pavement structures. "n order to provide ma2imum structural support, the
subgrade soil must be compacted to a density of no less than ?/4 as specified in !ection %?-
/.1of the !tandard !pecifications.
"f it is not, the subgrade will continue to compress, deform or erode after construction, causing
undesirable pavement cracks and deformation. "n order to achieve these densities the subgrade
must be at or near its optimum moisture content #the moisture content at which ma2imum dry
density can be achieved$. sually, compaction of insitu or fill subgrade will result in ade6uatestructural support. !ubgrade soil can vary widely over a short distance. &oor subgrade can be
described as e2pansive #plasticity inde2 greater than %) and -value of less than %1$. ;ecessary
tests such as sieve analysis, plasticity inde2, and -value should be performed. The engineer
should determine the 6uality of the subgrade if it is structurally ade6uate. "f the structural support
offered by the in situ compacted subgrade is estimated to be inade6uate, there are options that
can be used. 9rganic and peat soils are compressible and should be removed and replaced with a
better soil prior to placing the pavement structure. 'or e2ample, lime may be used with
e2pansive soils@ cement with less plastic soils #plasticity inde2 less than %1$ and emulsified
asphalt can be used with sandy soils. The binding characteristics of these materials generally
increase the subgrade load bearing capacity. Compaction of not less than ?/4 must be obtained
for a minimum depth of )./ feet below finished grade for the width of the traveled way and
au2iliary lanes including .1 feet on both sides as re6uired in the !tandard !pecifications. The
minimum depth of )./ feet can be waived in the following situations a portion of a local road is
being replaced with stronger pavement structure, partial depth reconstruction, presence of,
intersections, or frontage roads. ocation where the )./1 feet compaction depth is e2isting
utilities are to be moved and interim widening project is re6uired on low volume roads any
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imported borrow to replace soft or unsuitable material or use of subgrade enhancement fabric in
construction should be identified and shown. There is no minimum California -value re6uired
by the !tandard !pecification for imported borrows@ therefore a minimum must be specified by
!pecial &rovision to cover the material placed within ( feet of the finished grade waived must be
shown on the typical cross sections of the project plans
.
.-.1.% Su55ase *ayer Prearation
The subbase layer is a planned thickness of specified material between a base and the subgrade
or basement material. nbound aggregate or granular material primary purpose is for structural
support, and other uses include #i$ improve drainage, #ii$ minimi+e frost action damage #iii$
minimi+e intrusion of fines from the subgrade into the pavement structure. The *epartment uses
Class ) Aggregate !ubbase, as shown in
Table >).%D to Table >).%:in the Caltrans E*:, for use in CC& to provide a foundation or
working platform for the base when placed on the subgrade. Aggregate may include any of the
processed materials from reclaimed asphalt concrete #AC$ lean concrete base #CD$, cement
treated base #CTD$, &ortland cement concrete #&CC$, or it consists of any combination of these
materials, but there claimed material amount should be less than /14 of the total volume of the
aggregate used. Aggregate subbases are delivered as uniform mi2es and deposited to the roadbed
in layers or windrows, free from pockets of coarse or fine material and segregation should be
avoided.
!preading and compaction in one layer may be accomplished when the re6uired thickness is1./1-
foot or less. Fhere the re6uired thickness is more than 1./1-foot, spreading and compaction are
in ) or more layers of appro2imately e6ual thickness. The ma2imum compacted thickness of any
one layer does not e2ceed 1./1 foot. Compaction of aggregate subbase is specified in !ection )/-
%.1/, HCompactionI of the !tandard !pecification
-.1.' ase *ayer Prearation
The base layer is immediately placed beneath the surface course. "t provides for additional load
distribution and contributes to drainage #if permeable base is used$ and frost resistance. The
*epartment uses Eot :i2 Asphalt #E:A$ #Type A$ to provide a construction platform
underneath the CC&. E:A #Type A$ provides a smooth base layer, and a good bond breaker layer. E:A #Type A$ provides fle2ibility to e2pand and contract with temperature fluctuations.
E:A #Type A$ base layer consists of a combination of mineral aggregates and asphalt materials
mi2ed mechanically in a plant. "t consists of one or more layers placed on a prepared subbase
inconformity with the alignment and grades shown on the project plans. "t is placed at a
temperature of not less than %1 L' and only when the subbase surface is dry and in satisfactory
condition. Fhen re6uired, a prime coat of li6uid asphalt can be applied to the area of the
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subgrade or the subbase to receive the E:A base. Tack coat #paint binder$ shall be applied
between lifts of E:A base. All loose material must be completely removed from the primed
subgrade before placing E:A base.
!ection ?->-!preading and Compacting
!tates that all breakdown compaction must be completed before the temperature of the E:A
mi2ture falls below )11 L'. E:A #Type A$ base is spread and compacted in a number of lifts.
ayer shall be placed over a layer, which e2ceeds1.)1-foot in compacted thickness. The
compacted thicknesses are 1.)1-foot minimum and 1.(1-foot ma2imum. "n order to provide
ma2imum structural support, the completed deep lift of asphalt base course shall have an average
density of at least ?0 percent of the laboratory density, based on the =ob-:i2 'ormula for the
asphalt mi2ture when tested in accordance with California Test 1( and A!T:* %%00,
California Test 10, or California Test 3/
-.% Reinforcing Steel Placement
&roper placement of reinforcing steel is crucial to performance of CC&. CC& failures are
usually associated with insufficient reinforcement bar lap splice, unconsolidated concrete around
the steel, improper positioning of the steel in the slab and e2treme hot weather during
construction. einforcing steel for CC& has been placed by two general methods manual
method or mechanical method. Eowever, a number of states have found longitudinal steel
placement not precisely spaced and deviations of M inches in the vertical plane when
mechanical placement using tube feeders was employed to position the steel
The *epartment currently does not allow the mechanical method. Therefore, reinforcing steel
shall be placed manually #see 'igure 3$ before the concrete is placed. The advantage of the
manual placement method is that it allows for easy checking of bar placement, height and lap
splice length. Eowever, the manual method is slower and more labor intensive than the
mechanical method.
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!igure 6. 7anual Placement of Reinforcing Steel
!ince the transverse steel is placed (.1 to (.3/ inch below the surface in the finished slab, small
;o. ( metal chairs #welded to the transverse bars$ or HplasticI chairs #tied to the transverse bars$
must be used to support the top longitudinal reinforcing steel in order to achieve this elevation
before concrete is placed. The metal chairs are positioned with its wide base perpendicular to the
transverse bar@ either type of chair is placed on the E:A base without fastener as illustrated in'igure 0. The chairs must be strong enough to hold the reinforcing steel in place during concrete
placement, consolidation, and finishing
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!igure 8. Plastic C3air (*eft) and Steel C3air (Rig3t).
typical placement process involves #i$ placing the transverse bars on chairs, #ii$ arranging the
longitudinal bars on top, and then #iii$ tying the longitudinal bars to the transverse bars.
Typically, longitudinal reinforcements are tied or clipped to the transverse bars every % to feet.
'igure % shows reinforcing bars in their final position just before concrete placement.
-.' Concrete Placement
The placement of concrete in CC& can be done using any e6uipment or procedure used to
place concrete for =&C&s e2cept that because reinforcing steel must be placed prior to placing the
concrete, concrete delivery trucks are not allowed to end-dump in front of the paving machine.
Therefore, drive over unloader and a belt placer machine which runs parallel and in front of the
paver may be needed in paving. These are the same devices used when placing e2isting =&C&
where it is not possible to end-dump in front of the paving machine #such as widenings where
access to end-dump is limited or dowel bar baskets are used.$The concrete truck comes behindthe paver, drives on to the drive over unloader and dumps the concrete. The conveyor belt that is
connected to the drive over unloader then places the concrete in front of the paver for forming.
se of these machines re6uire a minimum %0 ft. wide alongside and right of the area to be paved
for the drive over unloader use and for the haul truck to get in and out easily of the drive over
unloader. Decause of its si+e, the belt placer machine and drive over unloader are hard to moved
or stored easily. Consolidation, finishing, curing, and jointing processes follow concrete
placement, and they are briefly described below
5 Consolidation is the process that compacts fresh concrete to mold it within and around the
forms and steel reinforcements and to remove voids. The consolidation re6uirement can be foundin !tandard !pecification (1-%.13A B !tationary !ide 'orm Construction
5 'inishing involves any e6uipment or procedures used to impart the specified surface
characteristics. The preliminary and final finishing re6uirements can be found in !tandard
!pecification (1-%.1? and (1.%%1.
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9 Curing is the moisture and temperature in the concrete as it sets and hardens such that the
desired properties can develop. The curing re6uirement can be found in !tandard !pecification
?1-3.1).
5 !awing joints involves all sawing operations conducted on the pavement to create weakened
plane joints, and longitudinal and transverse contact #construction$ joints to insert appropriate joint seals. Eowever, CC& uses longitudinal reinforcing steel in order to limit the number of
weakened plane #a.k.a. contraction$ joints. !awed joints should be cleaned as specified. Timing is
a key factor in sawing weakened plane joints and should be done as soon as the concrete is
capable of supporting the weight of the saw. efer to Caltrans !pecification (1-%.10D #%$ B
H!awing :ethodI
6.0 S"&DRD P*&S
Table ) lists Caltrans standard plans for use with CC&, and can be found at the Caltrans internet
website at http88www.dot.ca.gov8h68esc8oe8projectplans8ET:81>plansdisclaim!.htm.Contact the *ivision of *esign, 9ffice of &avement *esign, for more detailed information about
these plans.
"* % *ist of Related Standard Plans Plan S3eet &um5er Standard Plan "itle
Descrition
&( Continuously einforced
Concrete
&avement se for new construction, reconstruction,
widening, and lane replacement.
&? Continuously einforced
Concrete &avement
B !lab eplacement
'or CC&, it is used for all locations needing slab
replacement. &lan shows where necessary saw cutting
will be needed.&%1 Concrete &avement B
*owel Dar *etails
se for all locations needing end panel pavement
transition.
& %0 Concrete &avement B ane
!chematics and "solation
=oint *etail
!hows all general cases where isolation joints are to be
located. se on all new construction widening and
lane replacement.
&)1 Concrete &avement-=oint
*etails
se for all locations needing saw cutting. 'or CC&, it
is used for longitudinal joint and construction joint
where saw cutting will be needed.
&% Continuously einforcedConcrete &avement-
Terminal =oint *etails
!hows all general cases where terminal joints are to belocated. This plan is used on new construction of
future pavement, at e2isting asphalt concrete #AC$
pavement, and for new AC and temporary pavement.
&1 Concrete &avement-<nd
&anel &avement
Transitions !hows cases where end panel pavement
transitions are to be located. This plan is used where
concrete paving lane abuts to e2isting8new approach or
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sleeper slab or asphalt concrete pavement at transverse
joint.
&)A
and
&)D
Continuously einforced
Concrete &avement-Fide
'lange Terminals
se for new construction of Fide 'lange Deam
Terminal between the end of CC& and the ends of
bridge, approach slab or other pavement types. se
with !tandard &lan D>-)%.
&( Continuously einforced
Concrete &avement-ane
*rop &aving *etails
se for new construction, reconstruction, widening,
and lane replacements at lane drops for CC&.
&/ Concrete &avement-amp
Gore Area &aving *etails
se for new construction, reconstruction, widening of
e2it and entrance ramp gore areas ne2t to CC&.
&(/ Concrete &avement B
*rainage "nlet *etail ;o. %
se for all drainage inlet locations needing isolation
joints around concrete apron. Fhen use in CC&,
transverse reinforcements are terminated ) inches
from all edges of longitudinal isolation joint.
&(> Concrete &avement B
*rainage "nlet *etail ;o. )
se for all drainage inlet locations needing isolation
joints around concrete apron. Fhen use in CC&,
transverse reinforcements are terminated ) inches
from all edges of longitudinal isolation joint.
D >-)% =oint !eals :a2 movement
rating J )
se of construction of wide 'lange Deam Terminal
with e2pansion joints re6uiring Type D =oint !eal.# :r
J % K$ se with !tandard &lan & )A and & ) D.
8.0 S"&DRD SPC$* PRO:$S$O&S (SSPs)
Table lists some pavement CC& related !tandard !pecial &rovisions that may be used by the
pavement engineer on CC& projects. The *ivision of *esign pavement website at
http88www.dot.ca.gov8h68oppd8pavement8ssps.htmmaterials is also a good source of
information for CC& design.
"* '. CRCP Related Standard Secial Provisions
SSP ; SSP "itle Comments
(1-CC& Continuously einforced Concrete &avement !pecial &rovision for use in
the construction of all CC&
projects.
(1-)11, olled- !houlder umble !trips#&ortland Cement
Concrete "n "ndentations$
se when rumble strips are to
be constructed in new &CC
pavement. "f stage
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construction prohibits forming
the rumble strips in the new
concrete pavement because of
stage construction patterns,
use !!& (1-)%1.
(1-)11 !eal <2isting Concrete &avement =oint se for projects where new
joint seals are to be
constructed in e2isting
concrete pavement. "nclude
!tandard &lan &)1.
(1-)%1 eplace =oint !eal #<2isting Concrete &avement$ se for projects where
e2isting pavement joint seals
in concrete pavement are to be
removed and replaced. "nclude
!tandard &lan &)1.
<.0 COS" S"$7"$O&
The Table ( below shows appro2imate volume of concrete and steel reinforcement weight per
lane-mile of CC&. Decause there is no historical cost data available for CC&, the following
e6uation has been developed for estimating the cost per cubic yard of CC& #N8CO$.
nit cost of CC& J 1.?1PQunit cost of =&C& #N8CO$R S QFeight of steel reinforcement #lb8CO$ P
N1.>/8lbR
"* +
This e6uation is based on a cost estimating
procedure similar to that used for =&C&s e2cept
that there are no transverse joints or dowel bars.
There is an added cost for the reinforcing steel.
The cost of wide flange pavement terminalmeasured transversely in linear foot should be
estimated separately. "t is estimated that the
average cost in installing wide flange terminal
joint is N3/1 per linear foot 6uoted from Te2as *9T statewide average price dated August )11>
and adjusted for California prices. The payment will be full compensation for all steel beams,
stiffener plates, end plates, drilled holes, welding, cutting, styrofoam, joint filler, concrete,
"3ic4ness of
Pavement
/eig3t of Steel
Reinforcement er lane=
mile
ft l5s > cy
1.01 %/,>>>
1.0/ %/,(/%
1.?1 %/,(/%
1.?/ %/,(/%%.11 %/,%)1
%.1/ %/,(0(
%.%1 %/,)0
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reinforcement, bond breaker, and for all material, labor, e6uipment, tools, and incidentals
necessary to complete the work. ean concrete base, hot mi2ed asphalt, aggregate subbase, and
other base materials are paid for separately. Terminal joints Type A, D and C must also be
included in total cost when included in the project plans. These three types of joints are measured
and paid for in cubic yard of concrete. The estimated average cost of each terminal joint Type A,
D or C is ) to )./ times the cost per cubic yard of concrete of CC&. The payment will be full
compensation for all welding, cutting, styrofoam, joint filler, concrete, reinforcement, and for all
material, labor, e6uipment, tools, and incidentals necessary to complete the work.
10.0 7SUR7&" &D P?7&"
The 6uantity of CC& is measured and paid for by the cubic yard of concrete including
furnishing and placing the longitudinal reinforcements, transverse steel and tie bars. The volume
of concrete is calculated based on the width, thickness and length shown on the project plans.
Terminal joints are paid for separately.
11.0 R!R&CS C$"D
This Guide was developed with the help from the information provided in the following
documents
%$ HCC-Eighway &ave, *esign of Continuously einforced Concrete &avement for EighwaysI,
D. 'rank :cCullough, =une %??, a publication of C!".
)$ HTechnical Advisory, on HContinuously einforced Concrete &avementsI, =une /, %??1 of the
'ederal Eighway Administration.
$ H!tandard &lans of the Te2as *epartment of Transportation, a publication of Te2as
*epartment of Transportation
($ H&avement *esign Guide of the Te2as *epartment of Transportation.
/$ H!tandard !pecifications, :ay )11>I, a publication of California *epartment of
Transportation.
>$ HTerminal Treatment for Continuously einforced Concrete &avement, August )11I, a report
prepared by Construction aboratories, "nc
3$ HEighway *esign :anualI of the California *epartment of Transportation.
0$ HConstruction of Continuously einforced Concrete &avement, %??I, a publication of
C!"?$ H'igures used in this guideI, courtesy of Concrete einforcing !teel "nstitute #C!"$.
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