内爆炸下肋环型球面钢网壳的泄爆阈值研究

Study on the Explosion Venting Threshold of Ribbed-type Spherical Steel Reticulated Shell under Internal Explosions

利用有限元软件LS-DYNA建立包含TNT炸药、网壳杆件、梁、柱、地面、围护结构（墙面和屋面）以及连接构件在内的单层肋环型球壳在内部中心爆炸下的数值模型。基于该模型,计算分析TNT炸药量和连接构件抗拉刚度的变化对墙面和屋面破坏模式的影响。将墙面和屋面的破坏模式进行归纳分类,通过提取围护结构表面有限测点的冲击波压力,得到不同破坏模式下结构的极限冲击波超压值ΔPlimf（泄爆阈值）。研究结果表明：连接构件抗拉刚度和TNT炸药量对墙面和屋面的破坏有较大影响,TNT炸药量一定时,连接构件抗拉刚度越大,围护结构破坏程度越低;基于墙面和屋面的破坏模式所建立的泄爆阈值与连接构件抗拉刚度的变化范围可为工程泄爆设计提供有效参考。

A numerical model for ribbed-type spherical steel reticulated shell under internal center explosion which contained TNT,reticulated shell member,girder,column,ground,building envelope（wall and roof）and connection member was established by using the finite element software LS-DYNA.Based on this model,the influences of TNT equivalence and tensile stiffness of connection member on the failure mode of wall and roof were calculated and analyzed.The failure modes of wall and roof were classified and the limit overpressureΔPflim（explosion venting threshold）for various failure modes was obtained by extracting the shock wave pressure data of finite points on building envelope surface.The numerical results show that：（1）tensile stiffness of connection member and TNT equivalence of dynamite have a significant impact on the failure of wall and roof,when the TNT equivalence of dynamite is constant,the greater the tensile stiffness of the connection member is,the lower the destruction degree of the envelope,（2）the variation range of explosion venting threshold and tensile stiffness of connection member which was established by failure modes of wall and roof can provide effective reference for explosion venting design.