Three-Dimensional Failure Criterion of Asphalt Mixtures in Asphalt Pavement

Abstract

Material resistance and performance are determined by the failure criterion for an asphalt mixture, affecting the scientific design of pavement. Conventional tensile, compression, bending, and split tests for asphalt mixture cannot fully reflect the complex stress and strain state of the pavement structure. In this paper, double confining pressure triaxial tests were performed on asphalt mixtures to generate three-dimensional complex stress states. In octahedral stress space, a failure criterion was established featuring the tensile and compressive meridians as well as the failure envelope curve. According to the generalized Hooke’s law (GHL), a transformed three-dimensional strain failure criterion model (FCM) was established and its accuracy was validated by the axial strain. The correlation function between stress and strain FCMs was proposed. According to the elastic layered system theory and the principle that the load response is less than the structural resistance, a three-dimensional load check was performed on a typical asphalt pavement structure. The results show that top-down cracks tend to appear in the inner edge of the load at the top of the upper surface layer. This research provides theoretical support for the study of the characteristics of asphalt mixture strength and pavement design under complex stress conditions.