Study on influencing factors and distribution probability of asphalt mixtures’ rutting samples physical indices

Abstract

Rutting deformation is one of the most prominent diseases in asphalt pavement’s early damage. In this study, the main influencing factors, mechanism, and distribution law of the principal physical indices of AC-13 asphalt mixture rutting specimens were analyzed based upon the rutting test and statistical principles. Firstly, the main influencing factors, mechanism, and changes law of AC-13 asphalt mixture rutting specimens’ main physical indices were analyzed, based upon a large number rutting test results. Secondly, it analyzes the optimum fitting distribution of the main indices based upon statistical principles. The results showed that, as the asphalt content increased, the mixture rutting samples’ ρf and VMA indices increased firstly and then decreased, VV increased and VFA changed in the converse direction. There was a good linear correlation between the indices Sa and Vbe and asphalt content, in which the indices showed an opposite change trend. The content of coarse aggregate increased by 5.5% in the asphalt mixture, the rutting samples’ ρf increased by 2.03%, and the indices VV, VMA, VFA, Sa, and Vbe decreased by 35.23, 9.1, 8.86, 35.79, and 7.60% on average, respectively. The Marshall testing specimens’ ρf, VV, and VMA were similar to those that were wheel rolled 18 times, and VFA was similar when rolled 12 times. As the number of times the mixtures were rolled increased by 6, the asphalt mixtures’ ρf, VFA, and Vbe increased by 2.05, 8.47, and 1.44%, while the indices VV, VMA, and Sa decreased by 29.49, 8.81, and 11.55%, respectively. The optimal distribution fitting function of the asphalt mixtures’ ρf, VFA, and Sa was the Weibull distribution, that of the Vbe indices was the Normal distribution, that of the VMA in asphalt mixtures was the Lognormal distribution, and that of VV was the Gamma distribution, which can provide a reference for the design and construction of highways’ pavement in this areas.