Determination of Interfacial Bond Behavior of Composite Concrete-Asphalt Pavement Systems

摘要

Described herein is a study of the interfacial debonding behavior between concrete and asphalt pavement material as found in whitetopping pavement applications. The study includes the interfacial failure resulting from both static and dynamic loading. Studies under static conditions used interfacial fracture mechanics techniques to investigate and characterize the behavior of pre-existing cracks along the asphalt-concrete interface. Experimental laboratory testing was done on uniaxially loaded rectangular block samples using asphalt material from two different age groups. It was found that the fracture toughness and interface strength increased with aging. Experiments were conducted with interfaces both normal and inclined to the loading direction, thereby allowing variation in the shear loading component. Results indicated that as shear loading component increased, the interface strength also increased. Finite element analysis was also used to explore the stresses in the laboratory block sample geometry. Finite element results of the stress distribution near the interfacial crack compared reasonably well with predictions from an idealized analytical solution. A special lap-joint specimen geometry was developed to determine the dynamic interfacial shear strength of bonded specimens using a Split Hopkinson Pressure Bar (SHPB) loading apparatus. Because of the small sample size, no pre-existing interface crack was used in this testing. Lap-joint samples were tested under both static and dynamic loading. Results indicated that at high loading rates the shear strength of the bonded lap joint was found to be about four times its static value.