半无限土体圆形隧道结构中地震波的传播

基于弹性波的散射理论，研究了半无限土体内圆形隧道中土体对SH波的多重散射和动应力集中，采用波函数展开法和镜像法，将待解问题归结为一组无穷代数方程组的求解，得到了问题的解析解.作为算例，给出了衬砌附近动应力集中因子的数值解，分析了围岩的剪切模量、入射波波数、半无限土体边界到衬砌的距离等参数对动应力集中因子的影响.数值计算分析表明:围岩的剪切模量、入射波波数等是影响动应力集中因子的重要因素.本文的研究方法和数值结果有望为衬砌的地震评价提供理论依据.

Seismic Wave Propagation Around Circular Tunnel Structure in Semi infinite Soil Body

Based on the scattering theory of elastic waves， the scattering of SH wave and the dynamic stress concentration around circular tunnel with lining were investigated by employing the wave function expansion and mirror methods. The analytical solution of the problem， which was taken as a group of unlimited algebraic equations， was derived， and the numerical solution of the dynamic stress concentration factor around the lining was given. The effects of the shear elasticity of the surrounding rock and the lining， together with the wave number on the dynamic stress concentration factors were analyzed. It is shown that the shear elasticity of the surrounding rock and the wave number are factors that influence dynamic stress concentration， which may provide important theoretical basis for the earthquake evaluation of lining.