Full-scale Reflective Cracking Test Update

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Full-scale Reflective Cracking Test Update

• Presented to FAA Airport Pavement
• Working Group Meeting
• By Hao Yin, Ph.D., P.E.
• Gemini Technologies, Inc.
• Date April 24, 2012

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Acknowledgement

• SRA
• Chuck Teubert
• Jerry Connelly
• Renaldo Aponte
• Jeff Stein
• Gupta Durgesh
• David Traverzo
• Pochtar Daniel
• Bing Xiao
• Henry Fermin

• FAA
• Dr. Satish Agrawal
• Dr. Gordon Hayhoe
• Donald Babargallo
• Ryan Rutter
• Frank Petch
• Murphy Flynn

• RMD
• Roy McQueen
• Christopher Deker

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Objective
Generate information from full-scale tests
(NAPTF) to assist in the improvement of current
design procedures for AC overlay on rigid airport
pavements.
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Scope
Evaluate the initiation and propagation of
bottom-up reflection cracks due to temperature
effect acting alone (thermally induced fatigue),
assuming intact PCC slabs.
Nunn, M., 1st RILEM 1989
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Key Parameters
1. Pavement Temperature T32oF, DT17oF
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Key Parameters
2. Horizontal Displacement at Joint 15 mils
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Key Parameters
3. Loading Rate ? 4. AC-PCC Interface Bond ?
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Progress Since 2011

• Laboratory tests
• Construction, instrumentation, and data
  collection
• Temperature Effect Simulation System (TESS)
  tune-up and enhancements
• Trial test

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Texas Overlay Tester
Determination of Loading Rate
Temp 32 oF Max Hori Dip 15 mils Loading Rate
0.25, 0.50, 1.0 mil/sec
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Overlay Tester Results
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Interface Bond Experiment
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Bond Strength Test
Temp 32 oF Loading Rate 0.05 mil/sec
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Bond Strength Test
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Bond Strength Test
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Temperature Unit Re-design
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Pavement Construction
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Pavement Construction
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Pavement Construction
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Pavement Construction
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Instrumentation Layout
South
1.5
ASG/CSG
ASG/CSG
L
T
L
L
12.0
Surface SG
T
ASG/CSG
ASG/CSG
L
L
T
L
ASG/CSG
ASG/CSG
T
T
T
T
1.5
North
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Data Collection
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Mishap Before Overlay
North
South
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Mishap After Overlay
E
Force, 92,000 lb
Force -85,000 lb
Ten
Com
N
S
56 mil
-46 mil
W
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Mishap After Overlay
E
Com
N
S
Ten
W
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Mishap After Overlay
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Crack Arrester
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Trial Test

• Feb 27 March 15
• AC/PCC interface temperature 32oF
• Max Hori Dis 0.015 in
• 600 sec per cycle
• 144 cycles per day
• Total of 2641 cycles

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Hydraulic Control
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Hydraulic Control Cont.
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Hori Dis Along Joint
North
South
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Pavement Temperature
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Crack Development36 Cycles
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Crack Development180 Cycles
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Crack initiation
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Dynamic Modulus
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Tensile Strength Field vs. Lab
Tensile Strength Field 200 psi
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Crack Development280 Cycles
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Actuator Force
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Crack Development2641 Cycles
37.5
17
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Surface SG Response
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Surface SG Response
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Surface SG Response
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Embedded SG Response
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Future Activities

• Experiment instrumentation
• Mill existing AC and overlay
• Full-scale test
• Laboratory tests
• Fracture energy of AC
• Creep compliance of AC
• Tensile strength of AC
• Thermal Coefficient of PCC

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Image Recording - North
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Image Recording - South