The Phase One I - 710 Freeway Rehabilitation Project: I nitial Design to Perf ormance Af ter Six Years of Traf f ic Meeting with AAPA Study Tour Group UCPRC, CA 8/ 10/ 2010 Richmond Field Station, UC Berkeley
I - 710 Project - Partnered Ef f ort (most recent participants) • Caltrans § T. Bressette, W. Farnbach, C. Suszko • I ndustry § J. St. Martin, • University of Calif ornia PRC § C. Monismith
I - 710 Project - Partnered Ef f ort (some earlier participants) • Caltrans § K. Herritt, R. Doty, J. Dobrowolski, S. Shatnawi • I ndustry § L. Nawrocki, J. Copley, R. Smith, D. Chapman • University § J. Harvey, F. Long
Presentation • Mix designs • Structural section designs § f ull- depth AC § overlay on cracked and seated PCC • Aspects of construction • Some lessons learned • Phase I I structures
I-710 March 2003
Rehabilitation of I nterstate - 710 • Full- Depth Asphalt Concrete § replacement under overpasses • Overlay of PCC (cracked- seated)
Design & Analysis Trial cross section Conditioning (Aging & Water) Trial mix design Perf ormance Tests Analysis Perf ormance Prediction Unacceptable Acceptable Final mix design & structural section
Long- Lif e Asphalt Pavement • QC/ QA specif ications • Polymer modif ied binders • I mproved aggregate requirements • Modif ied mix design method
Trial Mix Design • San Gabriel aggregate • Binders § Conventional: AR- 8000 § Polymer modif ied: PBA- 6a* • Hveem Stabilometer- to establish range of binder contents
Trial Mix Design • Range of binder contents § 4. 2 - 5. 7% (by wt of aggregate) • Conventional dense- graded mix, Caltrans specs. • All crushed materials
Final Mix Design - Rutting I nput N supply N demand Perf ormance test Traf f ic ≥ No N supply = M x N demand Yes
Shear Test
N demand - (PBA- 6A) • Design ESALs - f irst f ive years § 30 x 10 6 ESALs • N demand = 660, 000 M x Design ESALs x TCF x SF § M = 5 § TCF = 0. 116 § SF = 0. 04
Design Binder Content 10,000,000 Temperature = 50 C PBA 6A AR 8000 1,000,000 N @ γ p = 5 % 660,000 repetitions 146,000 repetitions 100,000 10,000 1,000 3 3.5 4 4.5 5 5.5 6 Asphalt content (percent by weight of aggregate)
HVS Rutting Study
Rutting Study Layout 25 m section 33 tonnes AC 4 m 150 mm 3 m K- barrier on Placed on jointed PCC one side of section
Mix Perf ormance Evaluation 30 38-mm ARHM-GG 25 62-mm ARHM-GG 75-mm DGAC AR-4000 76-mm PBA-6A 20 Rut Depth, mm 15 ½ inch rut depth 10 5 0 - 50,000 100,000 150,000 200,000 < 20,000 reps ~ 170,000 reps HVS Load Applications
Thickness Design - Fatigue Analysis I nput N supply N demand Perf ormance test Traf f ic No ≥ N supply M x N demand Yes
Design Considerations • Fatigue in asphalt concrete • Def ormation in unbound layers • Subsequently, design checked by CalME
Design Considerations Asphalt Concrete ε t ε v Base Subgrade
I nput • Structural section (f ull- depth) • Traf f ic (200 million ESALs) • Environment (T = 20° C) • Trial mixes & pavement section
I nput • Reliability (M=5) • f (traf f ic estimate & testing variability) • Perf ormance criterion § wheel path cracking ≤ 10%
Trial Pavement Sections PBA- 6A* AR- 8000 AR- 8000 (rich bottom) subgrade
Fatigue
Fatigue Test Results 1.E+08 1.E+07 1.E+06 Nf 1.E+05 AR-8000, 4.7% AC, 6% AV AR-8000, 5.2% AC, 3% AV 1.E+04 PBA-6A, 4.7% AC, 6% AV PBA-6A, 5.2% AC, 3% AV 1.E+03 1.00E-04 1.00E-03 Mean Strain
Fatigue N supply ≥ M × N demand ? Che heck vert i t ical subgrade st ra rain ! ! ! ! ! ! (co cont r t rolle lled t o t ot a t al l t hi t hick ckness)
Final Design AR-OGFC 25 mm 6% air voids PBA-6A (4.7%) 75 6% AR-8000 (4.7%) 150 3% AR-8000 (5.2%) 75 (rich bottom) subgrade
Overlays Asphalt Concrete 150 – 250 mm Fabric 30 mm Leveling Course 200 mm Jointed PCC Cement treated Base 150 mm Subgrade
Calculated Conf iguration Traf f ic loads applied statically symmetrical boundaries 250 mm p =725 kPa AC Cracks @ 1 m
Finite Element Mesh ~ 12,000 elements, NIKE2D
Bending Strains in Mix just above Fabric 160 5"@900, 4"@150 ksi 120 3"@900, 5"@150 ksi BENDING STRAIN (us) 3"@900, 3"@150 ksi 80 40 0 -40 -80 -120 -4 -2 0 2 4 6 DISTANCE FROM CENTER (ft)
Composite Overlay Final overlay thickness 25 mm OGFC 75 mm PBA-6A 225 mm 125 mm AR-8000 Broken and seated PCC Fabric
Full- Depth AC Comparisons • The Asphalt I nstitute • United Kingdom • Australia • Asphalt Pavement Alliance- U. S.
Perpetual Pavement Design Concepts 1.5 - 3” SMA, OGFC or Superpave } 4” Zone to Of High High Modulus 6” Compression Rut Resistant Material 4.5 - 6” Flexible Fatigue Resistant Max Tensile Strain Material 3 - 4” Pavem ent Foundation
Construction Specif ications • Perf ormance requirements based on shear and f atigue testing • More stringent compaction requirements • Tack coat between layers § Asphalt cement (AR- 4000)
Construction • Six stages • Stages 1 and 2 preliminary to rehab. of traf f icked sections • Stages 3- 6 - rehab. of traf f icked sections in 8 - 55 hr. weekend closures (vs. 10 originally planned) • Use of CA4PRS (construction management program)
Construction • Stages 3 - 6 § Traf f ic closure § Crack, seat, and overlay (CSOL) § Full depth AC construction (FDAC) § Traf f ic opening
Contractor Staging Plan N N N N N N st st nd nd rd and 4 rd and 4 th th ) ) Stage 3A (1 Stage 3A (1 ) ) Stage 4A (2 Stage 4A (2 ) ) Stage 4B and 4C (3 Stage 4B and 4C (3 FDAC: 406m FDAC: 406m FDAC: 840m FDAC: 840m FDAC: 362m FDAC: 362m CSOL: 480m CSOL: 480m CSOL: 1,035m CSOL: 1,035m CSOL: 1,259m CSOL: 1,259m th th Stage 6A (8 Stage 6A (8 th th ) ) Stage 5C (7 Stage 5C (7 ) ) Stage 5A and 5B (5 Stage 5A and 5B (5 th and 6 th and 6 th th ) ) FDAC: 342m FDAC: 342m FDAC: 321m FDAC: 321m FDAC: 840m FDAC: 840m CSOL: 760m CSOL: 760m CSOL: 959m CSOL: 959m CSOL: 1,160m CSOL: 1,160m Crack, Seat, and Overlay (CSOL) = 2.8 centerline Crack, Seat, and Overlay (CSOL) = 2.8 centerline - - km km Full Full - - Depth AC Replacement (FDAC) = 1.6 centerline Depth AC Replacement (FDAC) = 1.6 centerline - - km km
Placement of Leveling Course
I nst allat ion of Pavement Fabric
Placement of PBA- 6A* Mix
Digout and Placement of Aggregate Base – Working Platf orm
Rich Bottom Layer Construction
Monday, March 3 0 , 2 0 0 3 0 5 :0 0 am
Some Lessons Learned • Pre- bid conf erence mandatory f or all potential bidders • For projects of this importance a “partnering” meeting at the outset is mandatory § Partnering on the technical aspects extremely important!
Some Lessons Learned (cont. ) • For new test procedures included in Special Provisions insure that all involved groups perf orm tests and analyze resulting data the same way: § equipment calibration essential § preliminary testing of comparable specimens
Some Lessons Learned (cont. ) • I mproved specif ication requirements based on statistical considerations desirable • For QC/ QA activities adequate staf f ing imperative (large quantities of materials, up to 15, 000 tonnes per weekend)
Some Lessons Learned (cont. ) • Timely QA results required • Human resources – 3 to 5 weekend closures in a row maximum; if more required, allow 1 to 2 weekend interval
Some Lessons Learned (cont. ) • I n digout areas (FDAC) : § Exploratory testing imperative § Exact location of underground utilities
Some Lessons Learned (cont. ) • Contingency plan important § Digout areas - working platf orm; materials easily accessible § Standby HMA plant(s) • Meteorologist f or contractor (construction in digout areas)
Perf ormance Evaluation • FWD Def lection testing (2003 through 2008) • Back calculation of layer moduli and strains in HMA layers using MLEA • Condition surveys • Longitudinal and transverse prof ile measurements • Noise measurements • Laboratory testing of cores (RSST- CH) and slabs (Fatigue)
Perf ormance Evaluation • Non- destructive HWD tests § 11/ 03, NB and SB § 9/ 04, NB; 2/ 5, SB § 12/ 05, NB; 2/ 06, SB
Deflections – SB Lane 3 CENTER DEFLECTIONS LANE 3 I-710 SOUTHBOUND (ADJUSTED TO 19C) 800 PCH 405 Section 1(FD) Section 2(CSOL) Section 3(FD) Section 4(CSOL) Section 5(FD) 700 600 03 2003 DEFLECTION (MICRONS) 500 03 2004 05 2005 400 X 08 2008 300 200 100 0 0 50 100 150 200 250 300 350 LOCATION
CENTER DEFLECTIONS LANE 3 I-710 NORTHBOUND Deflections – NB Lane 3 (ADJUSTED TO 19C) 1000 PCH 405 900 Section 1(FD) Section 2(CSOL) Section 3(FD) Section 4(CSOL) Section 5(FD) 800 2003 03 700 DEFLECTION (MICRONS) 2004 03 600 2006 05 500 X 08 2008 400 300 200 100 0 0 50 100 150 200 250 LOCATION
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