双层柱面网壳结构在地下隧道内爆炸冲击下的动力响应分析

摘要

The dynamic response of a cylindrical reticulated shell structure under the impact of the blast waves generated by an in-tunnel explosion is investigated numerically. A three-dimension coupling model consisting of the underground tunnel > soil and a cylindrical reticulated shell structure is established with the ABAQUS software considering the material nonlinearity of the soil,concrete and steel. The accuracy and validity of the coupling model set up with the ABAQUS software is verified by an example. Three groups of cases, including the one-way and two-way tunnel layouts, the change of a distance between the cylindrical reticulated shell structure and the explosion-tunnel, and the change of the explosive position along the longitudinal axis of the tunnel, are analyzed systematically. The results show that setting another tunnel between the shell structure and the explosion-tunnel has an obstructive effect on the propagation of blast waves in soil, which can markedly reduce the peak response of nodes and member bars in the structure; increasing the clear distance between the shell structure and the explosion-tunnel can decrease the structural response effectively; changing the explosive position along the longitudinal axis of the tunnel will bring a remarkable influence on the distribution of internal forces of the cylindrical reticulated shell structure.%对双层柱面网壳结构在地下隧道内爆炸冲击作用下的动力响应进行了研究.借助ABAQUS有限元软件建立了考虑地基土、混凝土、钢材等材料非线性的隧道-土-网壳结构耦合体系的三维数值模型,并通过算例验证了所建体系模型的正确性和有效性.分别对单、双线隧道布局、网壳与爆炸隧道间距离的变化、爆炸点在隧道内沿其纵轴线移动等三组工况进行了系统研究.结果表明:网壳与爆炸隧道间增设的平行隧道会对爆炸波在土中的传播起到明显的阻挡作用,降低了网壳节点和杆件响应的峰值；增大网壳与爆炸隧道间的距离,可有效减小网壳的动力响应；爆炸点在隧道内沿轴线移动会对网壳结构的内力分布产生明显的影响.