动力作用下盾构隧道接头破坏行为研究

为揭示盾构隧道接头在高速列车动力撞击下的破坏行为,通过建立盾构隧道三维数值模型,对螺栓开裂与否两种工况下的管片接头破坏情况进行分析对比,同时捕捉管片接头与螺栓的动态开裂过程。研究结论:是否引入螺栓开裂对于管片纵向接头的开裂情况有较大影响,引入螺栓开裂后管片纵向接头部位不会出现完全破坏的单元,但其裂缝张开度总体上反而有所增大。撞击荷载下,管片纵向接头率先出现开裂的部位均为弯螺栓处,且环向弯螺栓呈环状断裂破坏,纵向直螺栓纵向剥离破坏。

Study on Destruction Behavior of Shield Tunnel Joint under Dynamic Loads

In order to reveal the destruction behavior of shield tunnel joint under high speed train dynamic impact,a three-dimensional numerical model of shield tunnel is established to compare the destruction status of segment joints under two different operating conditions with or without bolts cracking,and the propagation process of the cracking of segment joints and joint bolts is followed. The results show that the cracking of joint bolts has great influence on the cracking of segment longitudinal joints,the completely destroyed elements won't appear in the crack in segment longitudinal joints if joint bolts crack,but its opening will become greater. The place where the crack first appears on the segment longitudinal joints is always located at the bending bolt,and the circular bending bolt always tends to suffer circular fracture failure,and the longitudinal straight bolt often encounters longitudinal stripping failure.