ABSTRACT
ABSTRACT: This study evaluates cracking in asphalt concrete. Semi-circular notched asphalt concrete specimens are fractured in the laboratory using a strain-based load in three point bending. Crack opening displacement (COD) data is captured in real-time along the length of the crack using linear variable displacement transducers (LVDTs). Several parameters derived from the laboratory data are used to characterize the mix cracking in terms of resistance to crack initiation and crack propagation in dry and wet conditioned samples. These parameters are the crack initiation load, the ultimate load, the slope of the crack propagation curve, and crack velocity. The effects of mix type, air voids, and moisture conditioning on these parameters are evaluated. It is shown that wet samples can carry a higher ultimate load than the dry samples. Wet samples tend to show higher load decrease (higher slope) during crack propagation than the dry samples. Mix type and void ratio have very little effect on the crack velocity, although wet samples have slower cracks than dry samples.
