列车撞击作用下盾构隧道管片接头错动和张开分析

建立盾构隧道三维数值模型,在管片内侧施加特定速度和角度的列车脱轨撞击荷载,获取与被撞击块相连6颗螺栓所在位置的接头错动及张开量时程曲线。通过对比分析在撞击过程中不同位置接头的错动和张开量变化趋势以及出现的最大张开、错动量,揭示在列车小角度撞击作用下盾构隧道管片接头张开和错动特性。结果表明:在速度200 km/h列车斜向12.5°撞击作用下,各螺栓位置的管片接头均出现不同程度的张开和错动,在撞击过程中各位置接头出现的最大错动量均远远超过实际工程中的限值;相对于管片接头的错动,撞击作用所造成的各位置接头平均张开量相对较小,某些位置接头在整个撞击过程中始终未发生张开。研究所得结论对盾构隧道的结构防撞和防水设计具有一定的参考价值。

Analysis of Dislocation and Opening of Shield Tunnel Segmental Joints Subject to the Impact of train

A three-dimensional numerical model of shield tunnel is established with ABAQUS software,and specific velocity and angle of impact load of train derailment is applied in the medial segment to obtain the time history curves of dislocation and opening of the joints where the 6 bolts are connected to the segment impacted. In order to reveal the characteristics of the opening and dislocation of shield tunnel segmental joints subject to small angle impact of train,a comparative analysis of the trend of dislocation and opening and the maximum opening and dislocation of joints during the process of impaction at various locations are conducted. The results show that different degrees of opening and dislocation of segment joint bolts occur when a train hits the segment at the speed of 200 km/m and in 12. 5° angle; the maximum dislocation of joints is far over the limit value in practical engineering; compared with the segment joint dislocation,the average opening of the segment joint bolts under the impact is relatively small,and some joints even remain without opening. The conclusion of the study may provide a certain reference for the design of shield tunnel structure in anti-collision and waterproof.