内爆炸作用下地铁车站结构的动力响应与破坏分析

地铁车站环境封闭,一旦其内部发生意外或恐怖爆炸事件,结构会在爆炸波的冲击作用下产生强烈的动力响应和局部破坏.采用数值方法对地铁车站在背包炸弹等中小型爆炸装置产生的内部爆炸作用下的结构动态响应进行了分析,得到了梁、板、柱等主要受力构件的位移和应变等动力响应,同时分析了炸药量、构件配筋率以及土-结构相互作用等因素对结构主要受力构件响应的影响.研究表明:在内部爆炸作用下,地铁车站的站台板是结构中破坏最为严重的构件,临近柱和中板会产生开裂等轻微破坏;结构的动力响应随炸药量的增大而增大,随构件配筋率的增大而减小;土-结构相互作用对于距离爆源最近的梁、板、柱构件响应影响较小.

Dynamic Response and Damage Analysis of a Subway Station Structure due to Internal Explosion

Strong dynamic responses and local damages might occur in the subway station structure once an accidental or a terrorist explosion happens internally due to its enclosed environment.The responses of a subway station structure to internal explosions from typical small explosive devices,such as suitcase bombs,were simulated.The dynamic displacement and strain of typical columns,beams and floors were derived for estimating the safety of the structure.Parametric studies were also carried out to investigate the influences of TNT equivalent charge weight,reinforcement ratio of concrete members and soil-structure dynamic interaction on the dynamic responses of the structural members.The results showed that the platform floor was the most seriously damaged member under the internal explosion,while minor damage such as small cracks might occur in the members near the explosion.Dynamic responses of the structure would get stronger with the increase of the TNT equivalent charge weight,and weaker with the increase of reinforcement ratio.The soil-structure dynamic interaction need not be considered since it had little effect on the dy-namic response of the members near the explosion.