高速铁路隧道列车振动响应影响因素分析

Analysis of influence factors on dynamic response of high-speed railway tunnel under vibration load

运用有限差分法,建立了隧道-围岩相互作用的动力计算模型,分析围岩条件、列车运行速度、隧道底部结构设计参数以及基底状况对列车振动荷载作用下隧道结构动力响应的影响。结果表明:隧道衬砌结构动力响应随着围岩级别的提高、行车速度的增加和基底软弱层厚度的增加而增大,随着仰拱厚度、填充层厚度和仰拱矢跨比的减小而增大。隧道底部结构厚度和仰拱矢跨比的增大,能起到一定的减振作用,结构受力状态有所改善,但从控制变形角度考虑,依靠增加底部结构厚度来减小变形量,效果非常有限。

The dynamic calculation model about interaction between tunnel structure and surrounding rock was built by finite difference method.The influence of some factors on the dynamic response of tunnel structure with train vibration was analyzed,such as surrounding rock conditions,train velocity,the design parameters of tunnel base structure,the situation of foundation base and so on.The results show that the structure dynamic responses increase with the improvement of the level of surrounding rock;the increase of train velocity and thickness of weak layer;the decrease of thickness of invert arch,filling layer,and rise-span ratio of invert arch.The increase of thickness of base structure and rise-span ratio of invert arch can reduce vibration and improve the stress state,but the effect is very limited on reducing the deformation of the tunnel structure.