为了研究框架结构在地下室内部爆炸时的连续倒塌特性,运用有限元显式动力分析软件LSDYNA建立了一个含有1层地下室、4层地上结构的钢筋混凝土框架结构分离式模型;考虑钢筋和混凝土共节点的连接方式,采用三阶段模拟法将不同炸药作用位置时结构的连续倒塌模式进行对比,分析梁、板、柱等主要受力构件的具体破坏方式;阐释结构在地下室内部爆炸后的不同倒塌破坏模式。结果表明:地下室内部爆炸发生后地上一层破坏严重,在地下结构柱附近爆炸使得结构节点处破坏严重,从而导致结构的连续倒塌。
In order to study progressive collapse characteristics of frame structure in the basement under internal explosion,a finite element explicit dynamic analysis software LS-DYNA was used to build a four-story frame structure separate model with a single basement.With considering common node connections of reinforcement and concrete,three-stage simulation method was used to analyze and compare progressive collapse modes in different blast load positions.The concrete failure modes of main components,such as beam,slab,column,etc.were analyzed,and the different collapse mechanisms of basement structure under blast load were presented.The results show that serious damage occurs in the first floor after the explosion in the internal of basement,and the explosion of underground structure near the column causes the structural nodes seriously damage and collapses finally.