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

Acknowledgement FAA Dr. Satish Agrawal Dr. Gordon Hayhoe Donald Babargallo Ryan Rutter Frank Petch Murphy Flynn SRA Chuck Teubert Jerry Connelly Renaldo Aponte Jeff Stein Gupta Durgesh David Traverzo Pochtar Daniel Bing Xiao Henry Fermin RMD Roy McQueen Christopher Deker

Generate information from full-scale tests (NAPTF) to assist in the improvement of current design procedures for AC overlay on rigid airport pavements. Objective

Evaluate the initiation and propagation of bottom-up reflection cracks due to temperature effect acting alone (thermally induced fatigue), assuming intact PCC slabs. Scope Nunn, M., 1 st RILEM 1989

1. Pavement Temperature: T=32 o F,  T=17 o F Key Parameters

2. Horizontal Displacement at Joint: 15 mils Key Parameters

3. Loading Rate ? 4. AC-PCC Interface Bond ? Key Parameters

Progress Since 2011 Laboratory tests Construction, instrumentation, and data collection Temperature Effect Simulation System (TESS) tune-up and enhancements Trial test

Texas Overlay Tester Temp: 32 o F Max Hori Dip: 15 mils Loading Rate: 0.25, 0.50, 1.0 mil/sec Determination of Loading Rate

Overlay Tester Results 0.05

Interface Bond Experiment steel rakeheavy broom Straight Asphalt Emulsion

Bond Strength Test Temp: 32 o F Loading Rate: 0.05 mil/sec

Bond Strength Test

PG Straight Asphalt and Heavy Broom Bond Strength Test

Temperature Unit Re-design

P-401 (PG 64-22) Subgrade P-209 (Dense Graded Aggregate) P-501 5” 12” P-501 8” 6” Pavement Construction

Instrumentation Layout ASG/CSG T 1.5’ TTT T T T 12.0’ L L L L L L North South Surface SG

Data Collection

Mishap Before Overlay South North

N S E W Force, 92,000 lb Force -85,000 lb Mishap After Overlay -46 mil 56 mil Ten Com

N S E W Ten Com Mishap After Overlay

Crack Arrester

Trial Test Feb 27 – March 15 AC/PCC interface temperature: 32 o F Max Hori Dis: in 600 sec per cycle 144 cycles per day Total of 2641 cycles

Hydraulic Control

Hydraulic Control – Cont.

Hori Dis Along Joint NorthSouth

Pavement Temperature

Crack Development 36 Cycles

Crack Development 180 Cycles

Crack initiation

Dynamic Modulus 430,000

Temperature: 14 o F Loading Rate: 8 mil/sec (0.5 in/min) Tensile Strength Lab = 500 psi Buttlar et al Tensile Strength Field = 200 psi Tensile Strength: Field vs. Lab

Crack Development 280 Cycles

Actuator Force

Crack Development 2641 Cycles 17” 37.5”

Surface SG Response

Embedded SG Response

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

Image Recording - North

Image Recording - South