关键词: 道路工程, 沥青路面, 半刚性基层, 反射裂缝, 断裂力学, 应力强度因子

Abstract: Aiming at the cracking of semi-rigid base of asphalt pavement and the gradual reflection of cracks, the mechanical response research on the cracked pavement was carried out on the basis of analytical method. Firstly, based on the theory of fracture mechanics, a theoretical analysis model of the cracked asphalt pavement was established. Then, the system of partial differential equations was solved by Fourier integral transform, and dislocation density function was introduced to characterize fracture mechanics. The residue theorem was used to calculate complex integrals and singular integral equations were obtained. Lobatto- Chebyshev quadrature formula was applied to solve singular integral equations. Finally, the analytical expressions and numerical solutions of displacement, stress and stress intensity factors at any point of the road were obtained. Based on the engineering example, the main factors affecting the crack reflection of the base course were analyzed. The calculation results show that: under the action of vehicle load, shear failure is the main form of crack propagation, and the elasticity of semi-rigid base is the main factor affecting crack reflection. The research results can provide theoretical reference for the design and construction of semi- rigid base asphalt pavement.

Key words: highway engineering, asphalt pavement, semi-rigid base, reflection crack, fracture mechanics, stress intensity factor