爆炸荷载下地铁隧道损伤规律研究

地铁在运营中存在诸多风险，特别是外爆炸带来的危害尤为突出。为避免由此产生的风险，需对地铁隧道在外部侧爆炸瞬时强荷载作用下隧道衬砌结构损伤效应进行研究，进而对隧道衬砌结构的损伤程度作出判断。以西安地铁6号线工程为依托，利用ANSYS/LS-DYNA软件建立有限元模型，分析外爆炸荷载作用下应力波的传播规律；选取地面侧爆角度和隧道埋置深度2个因素建立分析工况，研究了外爆炸荷载下隧道衬砌结构的受力状态规律，隧道埋深15，18 m相较埋深12 m衰减了20，125个微应变；同时直观地对隧道衬砌结构的损伤程度进行分析。开展该项研究为地铁隧道结构抗爆防护设计提供了理论依据，具有较高的技术、经济和社会效率。

Study on damage laws of subway tunnel under explosive load

There are many risks in the operation of subway,especially the harm caused by the external explosion.In order to avoid the resulting risk,it is necessary to study the damage effect of the tunnel lining structure under the instantaneous strong load of explosion on the external side of subway tunnel,thus to judge the damage degree of the tunnel lining structure.Based on the project of Xi’an Metro Line 6,the finite element model was established by using ANSYS/LS-DYNA software to analyze the propagation laws of stress wave under the action of external explosion load.The analysis conditions were established by choosing two factors:the angle of side explosion on the ground and the buried depth of tunnel.The stress state laws of tunnel lining structure under external explosion load were studied.The microstrain attenuated by 10 and 125 for the buried depth of tunnel as 15 m and 18 m respectively compared with that for the buried depth of tunnel as 12 m.At the same time,the damage degree of tunnel lining structure was analyzed intuitively.The research provides the theoretical basis for the explosion proof design of subway tunnel structure,and has high technical,economic and social efficiency.