车辆荷载作用下超大断面双层隧道衬砌结构动力响应分析

Dynamic Response Analysis of Lining Structure of Double-layer Tunnel with Super Large Cross Section under Vehicle Load

针对大断面双层隧道结构力学复杂的特点,为了掌握其在运营期车辆荷载作用下的响应规律,对建立的三维隧道模型进行研究。对不同时刻的位移云图、位移进程曲线、加速度时程曲线进行分析,分析结果表明:在车辆荷载作用下,位移变化由大到小依次为车道、衬砌、围岩;位移响应在达到峰值后开始衰减直到荷载作用周期结束,并产生位移残余;加速度响应随着隧道轴线方向距离的增加而不断衰减,仅在出口段有所增加。通过车载作用下超大断面双层隧道的模拟,研究其衬砌结构的动力响应规律,可为运营期衬砌结构健康监控提供参考。

In view of complex mechanical characteristics ofdouble-layer tunnel structure with large crosssection,in order to master its response law under vehicle load during the period of operation,the established three-dimensional tunnel model is studied.The displacement nephogram,displacement process curve and acceleration time history curve at different times are analyzed.The analysis results show that:the displacement changes from large to small are respectively lane,lining and surrounding rock under vehicle load;the displacement response begins to decay after reaching the peak value until the end of the load action cycle,and produces displacement residual;the acceleration response decreases continuously with the increase of the distance in the direction of the tunnel axis,and only increases in the exit section.The dynamic response law of its lining structure is studied through the simulation of double-layer tunnel with super large crosssection under vehicle load,which can provide reference for the health monitoring of lining structure during the period of operation.