Analysis of cracking resistance of bituminous mixtures under monotonic and cyclic loads

Abstract

Although cracking resistance is one of the most important properties affecting the durability of asphalt mixtures, this property is often not considered as a requirement in the mixture design stage, and the bitumen content is determined from other properties (voids content, permanent deformation or water sensitivity, among others). The effect of bitumen content on the cracking resistance of an asphalt concrete mixture (type AC) is analysed in this paper by means of different types of tests. Firstly, a cyclic strain sweep test (EBADE test), to obtain the evolution of complex modulus and dissipated energy density with the number of cycles as well as the failure strain; the EBADE test can provided a first approximation to the fatigue law of the mixtures with different binder contents. Secondly, a direct tensile monotonic test (Fénix test) was used to determine strength and fracture energy of the mixture. The results from both tests were consistent between them.