【作者】 蔡袁强； 陈成振； 孙宏磊；

【Author】 CAI Yuan-qiang,CHEN Cheng-zhen,SUN Hong-lei (MOE Key Laboratory of Soft Soils and Geoenvironmental Engineering,Hangzhou 310058 )

【机构】 浙江大学软弱土与环境土工教育部重点实验室；

【摘要】 采用解析方法研究了爆炸荷载作用下饱和土中带衬砌隧洞的动力响应问题。模型假定圆形隧道中心处发生爆炸,采用Biot波动方程模拟饱和土体,衬砌运动方程基于Flügge壳体理论,通过引入两个势函数,在Laplace变换域中推导了爆炸荷载作用下圆形隧道位移和应力响应的表达式。利用Laplace数值逆变换得到爆炸荷载作用下衬砌与土体的时域计算结果,给出了不同土体渗透性参数b~*时饱和土中位移、应力的时程曲线,并于单相介质进行了对比,然后讨论了衬砌相对厚度对饱和土中响应的影响。数值结果表明,爆炸荷载作用下,b~*越大,位移和应力幅值振荡越显著,饱和土中应力和位移响应幅值小于单相介质;位移和应力的响应幅值随着衬砌相对厚度h~*的增加而减小,h~*越大,响应衰减越快。更多还原

【Abstract】 Using an analytical method,the dynamic response of a circular tunnel in the saturated soil is investigated.Assuming that the blast occurs in the center of the tunnel,a model is established.Biot’s theory is used to describe saturated soil.The motions of the liner are considered specially based on Fl(u|¨)gge theory.By introducing two potential functions,the analytical solutions of displacement and hoop stress induced by the blast loads are derived in Laplace transforms domain.Numerical results are obtained by inversion of Laplace transforms presented.The curves of displacement and hoop stress with time for different b~* on the interface between the liner and soil are presented.The influences of the relative thickness of liner are emphatically analyzed in saturated soil.It is shown that the amplitude of displacement and hoop stress increases with increasing the parameter b*.The amplitude of displacement and stress in saturated soil is smaller than that in elastic medium. That the attenuation of the responses becomes more apparent as the relative thickness of liner increase.更多还原