A comparative analysis of the fracture and fatigue properties of asphalt concrete and sulphlex

Abstract

A new approach to the characterization of pavement mixtures' toughness based on the J integral concept was developed. The fracture mechanics approach was used to compare fatigue and fracture characteristics of new plasticized sulfur binders with asphalt concrete. Crack growth rates were correlated with the J*-parameter which is an energy line integral. Crack growth rate tests were conducted on the TTI overlay tester. Fatigue characteristics were determined by laboratory experiments on the conventional beam fatigue tests. The variation of fatigue and crack resistance characteristics with temperature, rest time, type of material, displacement magnitude, displacement rate and thickness was examined. The results of the experimental analysis supported the notion of geometry independence of this approach. The results showed that crack growth rate correlated with the J* integral, while other parameters (K) failed to adequately characterize crack growth rate. A new concept for the prediction of crack resistance life based on material toughness as characterized by the J* and the critical energy release rate (J*(,IC)) was outlined.A procedure for estimating a shift factor between laboratory and field results that consider the effects of both strain and crack recovery was developed.