突加集中荷载作用下饱和土-深埋圆形隧道衬砌系统的非轴对称动力响应  

Non-axisymmetrical dynamic response of saturated soil and lining system with deeply embedded circular tunnel under step concentrated load

作　　者：陆剑骏 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）》2016年第5期665-679,共15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：考虑饱和土与深埋圆形衬砌的相互作用,研究了突加集中荷载作用下饱和土-衬砌系统的非轴对称动力响应.基于Biot理论和弹性理论,采用Laplace变换和Fourier级数,考虑衬砌边界条件以及衬砌与饱和土交界面处的连续性条件,在Laplace变换域内求得突加集中荷载作用下饱和土-弹性衬砌耦合系统的位移、应力和孔隙水压力等的解析表达式.利用Laplace逆变换Crump数值反演方法得到饱和土-衬砌系统动力响应的数值解,并分析了土体和衬砌系统的力学、几何等参数对系统动力响应的影响.结果表明:5倍隧道衬砌半径以外处土体的动力响应远小于隧道附近土体的动力响应;衬砌刚度和厚度对土体位移和应力影响显著,但对孔隙水压力影响较小;孔隙水的可压缩性对土体位移的幅值影响不大,但对应力幅值的影响较为显著.Considering the interaction between soil and lining in a deeply embedded circular tunnel, the non-axisymmetrical dynamic response of a saturated soil-lining coupled system under step concentrated load was investigated. Based on the Biot＇s theory and elasticity, using the Laplace transform and Fourier series, analytical expressions of displacements, stresses and pore water pressure of the saturated soil-lining system subject to step concentrated load were obtained in the Laplace transform domain under the boundary conditions of the lining and the continuity conditions on the interface between the saturated soil and lining. Numerical solutions of the dynamic responses of the saturated soil and lining system were obtained with a Crump method of the inverse Laplace transform. The influences of mechanical and geometric parameters of the soil and lining on the dynamic response of the system were analyzed. It was shown that dynamic response of the soil in a distance from the tunnel center more than 5 times of the radius was much less than that of the soil in the vicinity of tunnel. Influences of stiffness and thickness on displacements and stresses of the soil were significant, while the influences on pore water pressure were trivial. Furthermore, compressibility of pore water had stronger influence on the amplitude of the stress than that of the displacement of the soil.

关 键 词：饱和土 弹性衬砌 集中荷载 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]