Study on Multiple Failure Criteria of Asphalt Mixtures in Complex Stress States

Abstract

An asphalt mixture is always in a complex stress state during the service life of pavement. Its resistance can be objectively characterized only by applying the strength theory to establish the failure criterion model in a three-dimensional stress state. Therefore, based on the double confining pressure triaxial test method, the failure characteristic test in complex stress state was carried out on AC-13 and AC-20 asphalt mixtures widely used in asphalt pavement in China. Meanwhile, according to the generalized octahedral theory, the experimental data of the failure characteristic point, and the strength characteristics of the asphalt mixture itself, the applicability of classical failure criteria, including Bresler-Pister, Ottosen, Willam-Warnke, Kotsovos, Podgorski, amended Zhao-Song, and twin-shear failure criteria was analyzed. In the aforementioned failure criteria models, the amended Zhao-Song failure criterion considered the difference in tension and compression of materials, the effect of hydrostatic stress, and the correlation of stress states of strength, which was consistent with the test results. Therefore, this model can be used as the resistance calculation model of asphalt mixtures in a complex stress state.