Experimental and Numerical Analysis of Crack Initiation and Growth in Thin Film of Bitumen

ABSTRACT In order to estimate the influence of bitumen on the resistance to cracking and fatigue behaviour of bituminous mixes, a specific test has been developed to estimate fracture properties. A thin film of binder between two steel protuberances, simulating the pseudo contact of two aggregates, is subjected to successive tension loads with a constant strain rate during the test. Formation and evolution of the crack size during the test was investigated using numerical methods. This paper deals with the combination of the experimental evolution of the sample stiffness and modelling of the considered test by finite element method. The modelling method, described here, integrates both viscoelasticity with Prony series and the sample geometry. A quantitative method using stress intensity factor and displacement intensity factor is also presented to study the effect of strain rate on propagation of crack.