Mechanical response of interlayer structural shear performance of asphalt pavement with functional layer considering interlayer contact state

To explore the mechanical response of asphalt pavement structure with functional layer, and make asphalt pavement have better service performance, a structural combination form of asphalt pavement with functional layers is proposed in this study, and the interlayer structural mechanical response analysis is carried out based on the theory of a multi-layer flexible layered system. The study first suggests a combined method of stress-strain and displacement at each point of the three-dimensional asphalt pavement structure under the combined compressive-shear load. Secondly, the shear strength of asphalt pavement structure with functional layer under the influence of compressive-shear combined loads, different longitudinal slopes, overload loads, and temperature-elastic modulus under different interlayer contact states are analyzed. Finally, the distribution of structural shear strain of asphalt pavement with a functional layer under different conditions is investigated. The results show that in the asphalt pavement structure with a functional layer, the functional layer is the weak layer of the base-surface layer, and the interlayer shear stress will change abruptly under the combined compression-shear load. The maximum shear stress and extreme strain values are mainly concentrated in the upper and middle surface layers, and they show a consistent trend of first increasing and then decreasing with the increase of the pavement depth. The functional layer can be used as a temperature buffer zone so that the asphalt pavement has good contact performance between the surface and base at 76 ℃ and good shear strength. The results of this study provide a theoretical foundation for studying the interlaminar shear resistance of asphalt pavement with functional layers.