roeslerfresno crcp overlay 2 22 2012 -...
TRANSCRIPT
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Unbonded CRCP Overlays
Jeffery Roesler, Ph.D., P.E.Professor
Department of Civil and Environmental EngineeringUniversity of Illinois Urbana-Champaign
FHWA-CRSI Creating Long Life Pavement Solutions -Continuously Reinforced Concrete Pavements Workshop
Fresno, CaliforniaFebruary 22, 2012
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Acknowledgements
• Illinois Department of Transportation– Dave Lippert, Amy Schutzbach, Chuck
Wienrank
• Mike Plei
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CRCP CRACKING PATTERN
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Presentation Overview
• CRCP in heavy traffic areas in Illinois
• CRCP Unbonded Overlay Basics• Review of CRCP Overlay Projects• Key design issues for CRCP overlays• Illinois Experience with Unbonded CRCP• Summary
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Example Urban CRCP
• Illinois experience: – I-90/94 Dan Ryan Expressway – Chicago– Other projects
• I-95 Georgia experience
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Illinois Conditions
• Wet and Freeze-Thaw Climate• Limestone-Dolomite aggregates
– CTE=5.5x10-6/F• Design Flexural strength = 750 psi• Temperature Ranges:
– 0F to 100F• Long. Bars = 26 - #7 @5.5inch• Tranverse bars = #4 bars at 48 inches
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ATLAS CRCP Testing
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Summary of CRCP Section Failure
Section one
Section two
Section three
Section four
Section five
Duration of testing(1)12 months(6/16/02-6/23/03)
11 weeks (6/30/03-9/13/03)
10 weeks (5/26/04-8/4/04)
9 weeks (1/3/04-3/6/04)
2 weeks (4/6/04-4/15/04)
Total load repetitions 246,800 118,600 163,400 64,300 1,800
Total ESALs 911 M 778 M 627 M 764 M 12.5 M
Approx ESALs at first failure 511 M 230 M 548 M >764 M N/A
Maximum load applied 222 kN 222 kN 245 kN 245 kN 156 kN(3)
Pavement temperature range 1-27°C
(2) 24-35°C 18-27°C -4-10°C 4-18°C
Failure description Extended punchoutsExtended punchouts
Extended punchouts
Section did not fail
Response loading only
34k
1i
ii 40
Pn18ESALs
÷
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Bituminous BaseAggregate Working Platform
Extended-Life CRCP DesignIllinois DOT (2005)
4 & 6 in.
40 Year
CRCP
Bituminous BaseAggregate Working Platform
12 to 24 inches
0.8% Steel Epoxy Coated
14 in.
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Dan Ryan Expressway, I-90/94 (2007)
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• Original CRCP design (1961)• 2006-2008 reconstruction for 500 million
ESALs and 40-year life.– Slab thickness = 14-in– Steel content = 0.80%– Steel depth = 4.5-in– Tied JPCP shoulder– 4-in dense graded HMA – Min. 12-in granular subbase– Fine grained subgrade (A-6 soil)
I-90/94 Dan Ryan Expressway Chicago
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CRCP – Dan Ryan Expressway 40 Year
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CRCP – Dan Ryan Expressway
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• 5 mile project (I-80 to Indiana)• CRCP design ESALs= 175 million (40 yrs)
– 12-in CRCP– 0.75% steel– Depth of steel = 3.5-in– Tied JPCP shoulder– 4-in dense HMA base– 12-in granular subbase (PGE)– Fine grained subgrade (A-6 soil)
Illinois State Toll Highway Authority I-294 Chicago (2005)
15
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• 12.5 mile project (I-80 to 95th)• CRCP design ESALs= >60 million (40 yrs)
– 13-in CRCP– 0.75% steel– Depth of steel = 3.5-in– Tied JPCP shoulder– 3-in dense HMA base– 24-in recycled concrete aggregate subbase– Fine grained subgrade (A-6 soil)
Illinois State Toll Highway Authority I-294 (2008-2009)
16
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Other Illinois DOT CRCP Projects“Extended Life”
I-80* Morris2003
14in CRCP6in HMA
12in CRCP
I-70* Marshall2002
12in CRCP5in HMA8in CRCP
I-290 Schaumburg
200314in CRCP
6in HMA
24in Aggregate
I-74 Peoria2006
11.5in CRCP
6in HMA
12in Aggregate
12 14
14
11.5
*overlays
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Continuously Reinforced Pavements• No man-made “joints”• Steel reinforcement bars• Numerous transverse cracks
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Concrete Overlays CategoriesConcrete Overlays
Bonded Concrete Resurfacing of Concrete Pavements
Bonded Concrete Resurfacing of Asphalt Pavements
Bonded Concrete Resurfacing of Composite Pavements
Bonded Resurfacing Group
Unbonded Concrete
Resurfacing of Concrete Pavements
Unbonded Concrete
Resurfacing of Asphalt Pavements
Unbonded Concrete
Resurfacing of Composite Pavements
Unbonded Resurfacing Group
Thin Thick
Bond is integral to design Old pavement is Support
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Pavement Overlay Comparisons Bonded
Concrete Overlays (BCOs)
Unbonded Concrete Overlays (UBOLs)
HMA Overlay on Intact CRCP
HMA Overlay on Rubblized CRCP
Con
stru
ctab
ility
Vertical Clearance
Not a problem (typically 50 to 100 mm (2-4 inches) thick)
May be a problem (typically 180 to 250 mm (7 to 10 inches) thick)
May or may not be a problem, depends on the overlay thickness
May be a problem, overlay may be relatively thick
Traffic Control May be difficult to construct under traffic
May be difficult to construct under traffic
Not difficult to construct under traffic
Not difficult to construct under traffic but rubblization adds time
Construction Special equipment and experienced operators needed
No special equipment required
No special equipment required
Special equipment required for rubblization
Perf
orm
ance
Existing CRCP Condition
Good condition with no MRD
All conditions (good to bad)
Good condition, may accelerate MRDs
Poor condition
Extent of Repair
Repair all deteriorated joints and cracks
Repair limited to severe damage
Repair all deteriorated joints and cracks
Limited repair required
Future Traffic Any traffic level Any traffic level Any traffic level Any traffic level Historical Reliability
Fair to Poor* Good Good Good to poor, depending on the support
Cos
t E
ffec
tiven
ess
Initial Cost Depends on pre-overlay repair, but usually high
Higher than conventional HMA overlay
Depends on the pre-overlay repairs
Requires a thick HMA overlay
Life Cycle Cost Analysis (LCCA)
Competitive if future life is substantial
Competitive Cost-effective unless the pavement is in poor condition
Competitive if pre-overlay repairs are required
(Smith et al. 2002)
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Unbonded Concrete Overlay
Concrete Overlay hol
Existing Concrete Pavement
heSeparator layer
- Asphalt Concrete Interlayer
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Unbonded CRCP OverlayObjective
• Isolate excessive movement of existing pavement from concrete overlay
• Limit concrete distress reflection into concrete overlay
• Provide uniform & non-erodible support to overlay
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Concrete Overlay Stress Distribution
-100
0
100
200
300
400
500
600
700
800
-60 -50 -40 -30 -20 -10 0 10 20 30 40 50 60
Distance from crack, in
Bot
tom
stre
sses
, psiO
OO
O
Noncrackked underlying slab Cracked underlying slab
Khazanovich et al. 2002
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CRCP Unbonded Overlays General Overview
• Existing pavement condition is fair to poor• Asphalt separator layer or “bond-breaker”
– Friction layer that provides uniformity– Durable, moisture insensitive layer– Allows deflection profiles of two concrete
layers to be independent• Roadway & roadside geometrics
– shoulders, ramps, guardrail modifications
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(Smith et al. 2002)
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Unbonded CRCP Overlays Abridged History
• 600 miles of CRC Overlays (6 to 9-inches) since 1959 (CRSI 1988) – Waco, TX first CRCP overlay (CRSI 1973)– IN, MD, MS, TX, OR, IL, PA, ND, IA, CT
(PCA 1976)• Oregon DOT (e.g., 1970 to 1975)
– 4 projects (29.6 miles)• TxDOT (e.g., 1972- present) > 10 projects• Illinois DOT (1967- present) - 8 projects
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Oregon I-5 CRCP Overlay(1970-1975)
CRSI 1988
7 to 9 inch CRCP over flexible pav’t
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TxDOT Experience• I-35W Johnson County (1965)
– 6-inch CRCP over 9-inch JPCP– ADT=22,000 w/ 14% trucks– 8.78 mile section
• I-45W Galveston area (1972-1976)– 6-inch CRCP over JPCP– ADT=50,000 – 15.5 mile total section (4 projects) CRSI 1988
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Recent TxDOT ProjectsCRCP Overlays
1. IH-30 in Paris District: existing pavement is JPCP2. IH-45 in Dallas District: existing pavement is JPCP.3. IH-35 in Wichita Falls District: existing pavement is CRCP.4. IH-45 in Houston District: existing pavement is JPCP.5. IH-20 in Fort Worth District: existing pavement is CRCP.6. IH-20 in Tyler District:7. IH-20 in Beaumont District: existing pavement is JRCP.8. IH-35W in Fort Worth District: existing pavement is JPCP.
from Moon Won
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Arkansas DOT Experience• I-40/55 West Memphis (1972)
– 6-inch CRCP over 9-inch JPCP– ADT=27,000 w/ 25% trucks (1986)– 1.7 mile section
• I-55 West Memphis (1980)– 6-inch CRCP over 9-inch JPCP– ADT=26,600 w/ 28% trucks (1986)– 2.2 mile section
CRSI 1988
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Unbonded CRCP Overlays Issues
1. Assessing existing pavement conditions2. Interlayer type and thickness3. Overlay structural design4. Pre-overlay repairs (?)5. Construction specifications and details
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Condition Survey Information• Failures / mile• Materials-related distress (freeze-thaw,
ASR, etc.)• Deflection or PSIt• Drainage condition
– Interlayer or subbase erosion
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CRCP Structural Evaluation Current Distress
Level Inadequate Marginal Adequate
Punchouts (M,H), # / lane km (#/ lane mi)
Interstate freeway > 6 (10) 3-6 (5-10) < 3 (5) Primary > 9 (15) 5-9 (8-15) < 5 (8) Secondary > 12 (20) 6-12 (10-20) < 6 (10)
Patch deterioration (M,H), % surface area
Interstate freeway > 5 2-5 < 2 Primary > 10 5-10 < 5 Secondary > 15 8-15 < 8
Longitudinal joint spalling (M,H), % length
Interstate freeway > 50 20-50 < 20 Primary > 60 25-60 < 25 Secondary > 75 30-75 < 30
Materials related distresses: D-cracking and ASR
All M to H severity with significant spalling & jt. disintegration
L to M severity with spalling & jt disintegration
None to L severity
Deterioration of past maintenance activities (patches and other repairs), % surface area
Interstate/Freeway > 8 3-8 12 5-12 15 10-15
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Resurfacing Threshold Values TxDOT
• < 1.2 failures/km/yr (2 failures/mi/yr) allowed for thin HMA overlay used
• 1.2-1.9 failures/km/yr (2-3 failures/mi/yr) allowed for BCOs
• > 1.9 failures/km/yr (3 failures/mi/yr) allowed for UBCOLs
Failu
res /
km
Time
Thin HMA Overlay
UBOL
BCO
1.2 F/km/yr
1.9 F/km/yr
Failu
res /
km
Time
Thin HMA Overlay
UBOL
BCO
1.2 F/km/yr
1.9 F/km/yr
•CTR 920-F
CTR 1990
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CRCP Pre-overlay repairs
Distress Types Repair Methods Wide transverse cracks with significant differential deflection
FDR
Punchouts FDR Unstable slabs with large deflections FDR
Slab stabilization Retrofit edge drains
Severely spalled joints or cracks FDR HMA filling
Pumping / Faulting (> 6 mm (0.25 in)) Retrofit edge drains Slab stabilization
Settlement Level-up with HMA Poor joint / crack load transfer Repair not necessary, but a thicker separation
layer should be considered Materials related durability problems: D-cracking or reactive aggregate
UBOLs can be constructed
after Smith et al. 2002, AASHTO 1993, ACPA 1990
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Interlayer or Separation Layer Properties
• Dense-graded HMA– Provide interface friction for crack development– >1-inch thickness to level up– Greater distress requires > interlayer thickness
• Interlayers with past performance issues– PE sheeting, chip seals, slurry seal, or curing
compound, open-graded AC– Erodible/stripping, not resistant to reflective
cracks, insufficient friction
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Separation Layer, con’t• Geotextile layer
– Nonwoven used for JPCP unbonded overlays
• Germany & Missouri
– Not used for CRCP, yet– If distress is high then GT
probably is not useful to stop low shear reflective crack
– Doesn’t level up surface– Durability?
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Structural Design MethodsCRCP Overlays
• Darwin M-E (MEPDG)– Results in better thickness values
• IDOT– Modified-AASHTO JRCP/CRCP Method– Subtract 1-inch for overlay
• TxDOT– Traditionally, AASHTO 1993 for thickness design
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5 Million ESAL’sSoil CBR or “k”
Soil CBR = 3.0
“k” = 100
100 ft Jointed = 10in.
CRCP = 8in.
CRCP 80% of Jointed
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Typical Illinois DOT (2007)New CRCP Thickness Design
Thickness ESAL, Millions
8 in. 5
10 in. 20
12 in. 100
14 in. (max) 300+
•CRCP overlay design minus 1-inch
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Construction Issues• Pre-overlay repairs
– Punchouts!– High severity spalling– Subgrade/Drainage problems
• Concrete Material Selection• Steel Content
– Minimum 0.60%• Interlayer provides friction
– Erodibility test of interlayer • Hamburg Test (after Zollinger et al.)
– Whitewash surface or debond base layer (?)
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IDOT CRCP Unbonded OverlaysHistory
• Constructed Unbonded overlays since 1967• I-55 and I-70 (3 sections) – 1967,1970, 1974
– Unbonded CRCP overlay of JRCP• I-74 Knox County - 1995• I-88 Whiteside Country – 2000-01• I-70 Clark County – 2002• I-57/I-64 Mt. Vernon – 2011-12
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I-70 CRCP Overlay Sections• CRCP Overlay (1967) – MP 31-35
– 8,7, and 6-inch CRC w/ 0.6, 0.7, & 1.0% steel• 6-inch HMA interlayer• 10-inch JRCP
– ADT = 14,000 w/ 34% trucks• 17 million (1986)
– CRS = 5.7 (1986) & R.I. = 86• 7.3% patching for 6-inch CRCP & 0% for 8-inch
– Overlaid in 1989
– Minimum req’d = 7 inches Lippert & DuBose 1988
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I-55 CRCP Overlay Sections
• 8-inch CRCP Overlay (1970)– Springfield, IL (MP 89-92)– 9-inch JRCP– Steel content= 0.6%– 4 inch HMA interlayer + 8 inch HMA overlay– ADT = 24,600 w/ 15% trucks– CRS=6.5 & R.I. = 85 (1986)– Crack Spacing = 2.9 ft (1986)– Percent patching= 0.1% (1986)– Total ESALs=9.2x106
Lippert & DuBose 1988
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I-55 CRCP Overlay Sectionscon’t
• 9-inch CRCP Overlay (1974)– Springfield, IL (MP 105-108)– 10-inch JRCP– Steel content= 0.6%– 4 inch HMA interlayer– ADT = 17,000 w/ 22% trucks– CRS = 7.2 & R.I. = 97 (1986)– Crack Spacing = 3.2 ft– Percent patching= 0% (1986)– Total ESALs=9.1x106
Lippert & DuBose 1988
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I-74 Knox County (1995)Existing
• MP 54-62 Westbound only– East of Galesburg
• Existing pavement cross-section (1969)– 3 to 4.5 inches HMA overlay– 7-inch CRCP– 4-inch HMA base
• Severe D-cracking and punchouts– Transverse and longitudinal cracks in HMA overlay– Full-depth concrete patches
McNeal 1996; Heckel 2001
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I-74 Knox County (1995)• 9-inch CRCP overlay w/ tied PCC shoulders
– Design ESALs = 24 million– Crack spacing = 3.1 ft (1997); 2.3 ft (2001)
• 2009 AADT = 14,800 (SU = 550, MU = 3300) – Annual ESALs = 1.070x106
• Condition Rating Survey (CRS) value– 8.3 out of 9.0 (2001)– 8.2 out of 9.0 (2009)
• IRI – 70 (2001); 69 (2009)• Transverse crack LTE = 92% (2001)
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I-88 Whiteside County (2000-01)
• IL 78 to west of Rock Falls
• Existing 8-inch CRCP (1975)– Crushed river gravel– blowups and D-cracking problems– HMA overlays in 1988, 1991– Recurring blowups and D-cracking
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I-88 Whiteside County (2000-01)
• 9.25-in CRCP unbonded overlay– 1-inch leveling binder placed on top of the
existing 3.25-inch HMA overlay
• 2010 CRS = 8.0 out of 9.0• IRI (in/mi) = 52 EB, 57 WB• 2009 AADT = 8800 (SU = 300, MU = 2300)
– Annual ESALs = 0.741x106
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I-70 Clark County (2002)General Project Information
• Originally constructed in 1969• 8-inch CRCP on 4-inch HMA base• Subsequent bituminous overlays totaling 7-
3/4 inches• Traffic (2-way)
– Current ADT of 24,000 with 42% trucks• Location = IL 1 to Indiana Line
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Proposed Pavement Cross Section
4” Asphalt Base
8” CRCPBITUMINOUS
SHOULDER
BITUMINOUS OVERLAYBITUMINOUS OVERLAY
MILL OR OVERLAY TO GRADE LINE
12” UNBONDED
CRCP OVERLAY
12” PCC
SHOULDERS12” PCC
SHOULD.
12 ft. 6 ft.24 ft.
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IDOT CRCP Design (I-70)• Pavement design = Chapter 54 of BDE manual
– 30-year design traffic of 116x106 ESAL’s (rigid)– New design = 13-inch slab thickness
• Thickness credit of 1-inch given in areas of unbonded overlay (NCHRP/Corps of Engrs.)– 12-inch design thickness w/ 0.80% steel (#7 bars)– Nominal 5-inches of HMA interlayer– 25 bars at 6-1/4 in. centers-longitudinally– #4 bars at 2-ft. intervals-transversely
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I-70 CRCP Overlay Warranty
• 5-year duration• Warranty bond required• Warrants materials and workmanship• 95% of pavements expected to not need
warranty work• Evaluated in 0.10-mile sections• Distress parameters defined in SHRP’s
“Distress ID Manual for LTPP” P-338
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Warranted CRCP Distresses• Transverse and longitudinal cracking
(moderate and high severity)• IRI limited to 150 in./mi.• Spalling of longitudinal joints• Scaling• Patch deterioration• Punchouts• Corrective actions defined for each distress
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I-70 Clark County (2002)Performance
• 12-inch CRCP overlay w/ HMA interlayer• 5 yr. warranty contract
– two dozen “punchouts” in 9 miles of pavement– problem (?) = 12-ft. full-depth PCC shoulders tied with
#8 bars had punchouts located at jointed shoulder.
• Overall performance very good– CRS = 8.1 (2010)
• IRI = 65 (EB); 69 (WB)• 2010 AADT = 20,500 (SU = 650, MU = 8000)
– annual ESALs = 2.55x106
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I-70 CRCP Overlay
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Example: Early-Age Punchout
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I-57/I-64 Alternatives (2010)
• HMA overlay of existing CRCP– Rubblization with HMA– JPCP and CRCP options
• MEPDG & IDOT designs• Milling options vs. rubblization• Interlayer type• Thickness options
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Poor Section I-57/I-64 NB
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Good Section I-57 NB
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MEPDG CRCP OverlayInputs
• 20-year design life– Mattoon-Charleston, IL Climate
• ESALs – 80x106
• A-7-6 soil type– k=200 psi/in
• Tied concrete shoulder– 40 to 80% LTE
• CRCP Steel properties – 3.5 inch depth, #6, 0.7%
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MEPDG CRCP DesignResults
• New CRCP = 11 inches– HMA base unbonded = 4inches
• Unbonded CRCP = 9 inches– AC base interlayer = 2 inches– CRCP (existing) = 8 inches
• Unbonded CRCP = 10.5 inches– HMA interlayer = 1 to 2 inches– CRCP (rubblized) = 8 inches
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I-57 / I-64 Mt. Vernon (2011)• Mill existing HMA overlay• Rubblize existing 8-inch CRCP• Place 3-inch HMA interlayer• 10.5-in. CRCP overlay w/ 0.7% steel
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National Performance
(Smith et al. 2002)15 sections in GA, IL, ND, WI, AR, MD, PA
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Performance Recommendations
• Concrete Overlay > 7 inches– Consistent with IDOT policy
• HMA Interlayer > 1-inch– Dense-graded
(Smith et al. 2002)
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LTPP Database
• 4 unbonded CRCP sections
• Georgia– 20-yr– HMA Interlayer = 0.75 inch– CRCP overlay 8.25-inch– Existing section 8-inch
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CRCP Overlay of JPCP in UK
• Refurbish 6.2km section of M25 London Orbital Motorway during 2000/2001
• Strengthened using hybrid solution of 200mm CRCPoverlay for most heavily loaded traffic lanes 1-2, with AC overlays for lane 3 & shoulder
• Existing 3-lane dual carriageway of un-reinforced concrete slabs with contraction joints at 5m centres– Road opened to traffic in 1979– 10mm AC OL in 1990– Large amount of pavement faulting due to underlying clay– AADT currently exceeds 120,000 vehicles approximately
15% classified as Heavy Goods Vehicles (HGV’s)
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M25 London Orbital Motorway, UK
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CRCP Unbonded Overlay Summary
• CRCP unbonded overlays– 7 to 12 inches– Steel content = 0.6 to 0.8%– #5 to #7 bars– design ESALs from 5 to 100x106 ESALs
• HMA interlayer– Dense-graded asphalt mixtures– >1-inch
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Current I-39 Section Issue• Existing CRCP (~10in) and JPCP (11,14 in)
with materials-related distress (?)• Constructed 1989
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Concrete Material Distress
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CRCP Polished Section
Lankard 2012
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Bibliography• Rasmussen, R., Rogers, R., Ferragut, T. (2009), Continuously Reinforced
Concrete Pavements Design and Construction Guidelines, FHWA-CRSI.• Harrington, D. et al. (2008), Guide to Concrete Overlays Sustainable Solutions for
Resurfacing and Rehabilitating Existing Pavements, National Concrete Pavement Technology Center, Iowa State University, Ames, IA.
• Smith, K.D., H. Yu, D. Peshkin, (2002), Portland Cement Concrete Overlays: State of the Technology Synthesis, Federal Highway Administration, Washington, DC.
• Lippert, D., DuBose, J. (1988), Performance Evaluation of Concrete Overlays, Physical Research Report No. 101, Bureau of Materials and Physical Research, Illinois Department of Transportation.
• McNeal, A. (1996), Planning , Design and Construction of an UnbondedConcrete Overlay, Physical Research Report No. 122, Bureau of Materials and Physical Research, Illinois Department of Transportation.
• Heckel, L.B. (2002), Performance of Unbonded Concrete Overlay on I-74, Physical Research Report No. 140, Bureau of Materials and Physical Research, Illinois Department of Transportation.
• Gagnon, J.S., Zollinger, D.G., and Tayabji, S.D. (1998), Performance of Continuously Reinforced Concrete Pavements: Volume V: Maintenance and Repair of CRC Pavements, FHWA-RD-98-101
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Bibliography, con’t
• CRSI (1988), Performance of CRC Overlays: A Study of Continuously Reinforced Concrete Resurfacing Projects in Four States, 26 pp.
• CRSI (1973), Design and Construction of Continuously Reinforced Concrete Overlays, 17 pp.
• PCA (1976), Continuously Reinforced Concrete Overlay: 1975 Condition Survey, 26 pp.