高速列车振动荷载作用下交叠隧道结构动力响应分析

Analysis of Dynamic Response to Overlap Tunnels under High-speed Train Vibratory Load

采用改进的激振力函数模拟高速列车竖向振动荷载,通过数值模拟计算方法研究了高速列车振动荷载作用交叠隧道的动力响应,分析了列车通行方式、隧道交叠角度以及列车速度对下穿隧道衬砌结构的动力响应变化.分析结果表明:当高速列车振动荷载施加在上跨隧道时,振动荷载对下穿隧道的影响比荷载施加在下穿隧道时,荷载对上跨隧道的影响大;列车通行方式和交叉角度对下穿隧道的动应力影响较大,其中下穿隧道衬砌结构的竖向加速度、位移和速度随着通车方式的改变和列车速度的增加而增大,但是随着交叠角度的增大,衬砌结构的加速度、位移和速度有所减小.因此,在实际工程中尽量增大交叠角度和避免上下同时通车,有利于隧道衬砌结构的稳定,同时达到减振目的.

Based on the numerical simulation of vertical vibrating load induced by high speed train with excita- tion function, dynamic response to overlap tunnel under the vibrating load was analyzed by the numerical simula- tion method. The factors of the dynamic response to undercrossing tunnel structure with train vibration was ana- lyzed, such as train passing method, overlap angle and train speed. The result shows that when the vibration load was applied on the crossing tunnel, the influence of vibration load on undercrossing tunnel was greater than the influence of vibration load on crossing tunnel when the vibrating load was applied on the undercrossing tunnel. Train passing method and overlap angle have greater influence than train speed. Vertical acceleration, vertical displacement and vertical speed of structure increase with the change of passing method of train and the increase of running speed, but decrease with the increase of overlap angle. Therefore, it is beneficial for the tunnel lining structure to increase the overlap angle and avoid opening the traffic up and down at the same time. By these ways the purpose of vibration attenuation has been achieved.