隧洞压力引起的非均匀初始应力场对饱和土的纵向动力响应的影响研究

Influence of inhomogeneous initial stress field caused by borehole pressure on longitudinal impedance of saturated soil

基于增量弹性动力理论研究了初始隧洞压力引起的非均匀应力场对初始均匀且各向同性饱和土体的纵向动力响应问题。研究了土体在初始应力场作用下的非均匀性,在平面应变的假定条件下建立了饱和土体的纵向动力方程并得到纵向振动的解析解答。最后分析了初始隧洞压力引起的初始应力场对土体纵向阻抗的影响,并与现有的解答进行对比。

Based on the theory of incremental elastic dynamics,longitudinal dynamic response of initially homogeneous isotropic saturated soil under influence of borehole pressure was investigated theoretically.Firstly,the radial inhomogeneity of soil medium was deduced.Then,the longitudinal dynamic governing equation of saturated soil body was deduced based on the plane strain assumption.Its analytical solution to soil’s longitudinal vibration was gained.Finally, the influence of inhomogeneous initial stress field caused by borehole pressure on the longitudinal impedance of soil was analyzed.The obtained solution was compared with the existed one.