双圆盾构隧道在内部爆炸荷载下的响应分析

Response Analysis of Dot Shield Tunnels Under Internal Explosion

以双圆断面为代表的新型断面隧道结构在软土地铁网络建设中逐渐增多,其在内部爆炸荷载下的动力特性尚未有研究.以软土地区双圆盾构隧道结构为对象,采用动力有限元方法分析了其与炸药接触和非接触两种状态下3种当量炸药爆炸后的动力响应,得出各工况下隧道结构的最终应力状态.结果表明,隧道结构与炸药接触时,3种工况下隧道结构都有不同程度的损坏,其破坏程度随炸药当量数增加依次增强;隧道结构与炸药非接触时,10 kg当量炸药爆炸后对隧道结构基本没有影响,而50,100 kg当量炸药爆炸后隧道结构已严重损坏.该结果对软土地铁隧道运营安全管理具有参考价值.

Dot shield tunnels as a new cross-section of tunnels gradually are increasing in soft metro subway networks, but few studies have been made of their dynamic behavior under internal explosion so far. Based on dynamic finite element method, the paper presents an analysis of the dynamic behavior of dot shield tunnels under the condition of contact and non-contact explosive including 3 kinds of explosive charge, stress states of dot shield tunnels under 3 loading conditions are obtained. Analysis results show that different damages of tunnels occur under the condition of contact, and the damage increases with the increasing of the explosive charge,no damage occurs under the condition of non-contact including 10 kg explosive charge, serious damage occurs under the condition of non-contact including 50 kg and 100 kgexplosive charge. The study result provides a reference for safe operation of metro subway.