轴对称爆炸载荷作用下深埋圆形隧洞的准饱和土动力响应  

Dynamical response of nearly saturated soil with deeply buried circular tunnel under axisymmetrical blasting load

作　　者：吴传侠[1] 张敏[1] 杨骁[1] 

机构地区：[1]上海大学土木工程系,上海200072

出　　处：《上海大学学报（自然科学版）》2015年第5期617-630,共14页Journal of Shanghai University:Natural Science Edition

基　　金：国家自然科学基金资助项目(10872124)

摘　　要：考虑准饱和土与隧洞弹性衬砌的非完整连接,基于Biot模型和弹性理论,研究了深埋圆形隧洞的准饱和弹性土在轴对称爆炸载荷作用下的动力响应.通过引入势函数和Laplace变换,得到准饱和弹性土-弹性衬砌耦合系统在Laplace变换空间中动力响应的解析解;借助Laplace逆变换的数值Crump法,得到了耦合系统的时程响应;分析了不同隧洞模型下准饱和土的动力响应.结果表明:准饱和土-壳体衬砌系统模型的土体响应最小,而无隧洞衬砌准饱和土模型的土体响应最大;饱和度对土体位移和应力影响较小,但对孔隙水压力有较为显著的影响;且随着接触面刚度的增大,准饱和土体的径向位移和环向应力幅值均增大.Considering the non-complete connection between nearly saturated soil and elastic lining of a tunnel, the dynamical responses of nearly saturated elastic soil with a deeply buried circle tunnel subject to an axisymmetrical blasting load are investigated based on the Biot model and elasticity. Analytical solutions of dynamical responses of nearly saturated soil and elastic lining coupled system in the Laplace transform space are derived with the potential function and Laplace transform. The time-history responses of the coupled system are obtained with a numerical Crump method of the inverse Laplace transform. The dynamical responses of nearly saturated soil with different tunnel lining models are analyzed. It is shown that the soil responses of nearly saturated soil and a shell lining system are minimal, while the soil responses of nearly saturated soil without lining are maximal. Influence of the degree of saturation on displacement and stress of the soil is weak, but has evident influence on pore water pressure. Furthermore, the magnitudes of radial displacement and circumferential stress increase as stiffness of the interface increases.

关 键 词：准饱和土 隧洞衬砌 爆炸载荷 动力响应 LAPLACE变换 

分 类 号：O327[理学—一般力学与力学基础] TU435[理学—力学]