Development of Full-Scale Reflective Cracking Test at the FAA National Airport Pavement Test Facility

Abstract

Asphalt concrete overlays must be designed and constructed to withstand reflective cracking. However, the current FAA overlay design procedure (Advisory Circular 150/5320-6E) does not address this common form of premature failure. This paper presents a research project that studied one of the accepted causes of reflection cracks: horizontal movements concentrated at joints in the existing portland cement concrete pavement. A prototype, the temperature-effect simulation system, was developed at the FAA National Airport Pavement Test Facility so that joint opening and closing caused by temperature changes could be simulated mechanically. A test pavement representing a typical airport overlay structure was constructed to support full-scale tests. Both theoretical and experimental studies were performed to determine key test parameters, critical pavement temperature, joint opening, loading rate, and the bonding condition at the interface of asphalt concrete and portland cement concrete. Preliminary full-scale tests demonstrated that the simulation system could not only generate forces that create precise and repeatable joint openings but also effectively control the pavement temperature. Instrumentation data revealed that once bottom-up reflection cracks were initiated, crack development could quickly progress. When the crack length reached a certain level, the crack propagation rate slowed considerably. Information and data presented in this paper will be of immediate assistance to general aviation airports that carry small and light aircraft and experience significant temperature variations.

Analysis of Temperature Variation and Thermally-Induced Reflective Cracking Potential in Composite Pavements

“…Details of the pavement structures are presented in Table 1 with the material properties of each layer. The pavement structure mimics the pavement section used for full-scale testing of thermally-induced reflective cracks conducted by the Federal Aviation Administration (FAA) ( 5 ). The pavement layer thickness and material properties are shown in Table 1.…”

“…Horizontal displacement was utilized to simulate thermally-induced joint opening of PCC. However, the developed system only considered the thermal contraction and expansion of PCC, the slab curling effect was not considered in the study ( 5 ). Based on full-scale testing, it was found that the inclusion of one-inch interlayer could extend overlay life by 15%.…”