Investigation of texture effects at interlayer bonding behavior between asphalt concrete (AC) overlay on Portland cement concrete (PCC)

Abstract

Slippage cracking in asphalt overlays occurs because of bonding failure between the asphalt concrete and Portland cement concrete layers. A direct shear test was adopted to simulate common and critical bonding failures. The effects of temperature and tack coat have already been studied by previous researchers; however, the effects of texture have not been sufficiently considered. In this study, clamping shear strength was used to characterize the pure shear strength of the pavement. It is defined as the difference between the total shear strength and plane shear strength. The results indicated that the interlayer behaved in an elastic manner at lower temperatures, generating brittle failures with cracking, whereas viscoelastic behavior dominated at higher temperatures, producing ductile failure that led to slippage at the interface layer. The surface texture effects can be quantitatively characterized using the clamping shear strength. In addition, the clamping shear strength can be used to optimize the asphalt mixture to enhance the bonding performance.