交叉隧道耦合动荷载动力响应及安全分析

Analysis of Dynamic Response and Security of Crossing Tunnel Based on Coupled Dynamic Load

研究目的:因立体交叉隧道会同时受到来自入射、反射、绕射等多元荷载耦合导致的振动,其所受影响相比一般隧道而言更大。因此,对立体交叉隧道只受高速列车荷载作用及同时受高速列车与地震等多元荷载耦合作用下隧道结构的动力响应规律进行定量分析,并确定多元荷载耦合作用下立体交叉隧道结构安全性,从而找出不同隧道存在形式在多元荷载耦合作用下隧道衬砌结构断面的不同危险部位。研究结论:(1)地震荷载的出现改变了原有荷载的传播模式,且隧道结构断面不同位置受其影响最大不一定在交叉断面;(2)多元荷载中的地震荷载是对立体交叉隧道上跨结构产生不利影响的主要因素;(3)进行立体交叉隧道抗震设计时,应该增加上跨隧道左拱腰和左拱脚以及下跨隧道拱顶和左拱腰等危险部位的配筋率及混凝土的厚度,同时研制抗拉性能更好的轨道板;(4)本研究成果可对立体交叉隧道多元荷载耦合作用下的抗震设计提供指导。

Research purposes： Because the fly - over crossing tunnel will be subjected to the vibration of the multi load coupling at the same time, such as incidence, reflection and diffraction, the influence will be greater than that of the general tunnel. Therefore, the dynamic response laws of the tunnel structure of the fly - over crossing tunnel which is only subjected to the action of the high - speed train, and is also subjected to the multi load coupling of the high - speed train and earthquake are analyzed quantitatively, the structural safety of the fly - over crossing tunnel under the action of multi load coupling is also determined, the different dangerous parts of tunnel lining structure section in different tunnels under the action of multi load coupling are found. Research conclusions ： （ 1 ） The occurrence of seismic load changes the mode of communication of the original load, and also shows that the maximum influence of the different position of the tunnel structure section is uncertain in the cross section. （2） Seismic loads in multiple loads are the main factors that have adverse effects on the upper span structure of the fly - over crossing tunnel. （ 3 ） Attention and improvement should be paid to the aseismic design of the fly - over crossing tunnel, the reinforcement ratio and the thickness of the concrete should be added to the left arch and left arch feet of the upper span tunnel and the vault and left arch of the lower tunnel, developing track plate with better tensile properties at the same time. （4） The research results can provide guidance for the aseismic design of the fly - over crossing tunnel under the action of multi load coupling.