爆炸作用下钢框架梁柱节点模型简化方法研究

陆晓彤 宋振森 吴媛媛

摘要 爆炸荷载作用下，梁柱节点的力学性能对整体结构的抗爆性能有直接影响，为研究梁柱节点性能，必须合理选取爆炸荷载作用下的简化分析模型。采用显式有限元软件模拟爆炸作用下钢框架结构的动力响应并提取了梁柱节点简化模型。首先用ALE流固耦合方法模拟爆炸作用，得到结构迎爆面上的冲击荷载分布和发展规律;建立钢框架结构空间模型，研究其在爆炸作用下的整体动力响应，结果表明爆炸荷载作用在框架结构中具有弱传递性和局部性;提出钢框架梁柱节点简化抗爆分析模型。针对简化模型建立有限元模型，分析其在爆炸作用下的动力响应，结果显示简化模型在关键点的位移、速度和加速度等指标与整体模型的响应吻合，证明梁柱节点简化模型用于防爆分析的是合理可靠的。

关 键 词 爆炸荷载;流固耦合;简化模型;钢梁柱节点;LS-DYNA

中图分类号 TU391     文献标志码 A

文章编号：1007-2373（2021）06-0091-06

Abstract The response of frame structure subjected to explosion load is effected by the behavior of beam-to-column joints. In order to study the performance of beam-to-column joints， a reasonable simplified analysis model subjected to explosion load is necessary. The dynamic response of steel frame structure under explosion is simulated by an explicit finite element software and the simplified model of beam-to-column joints is proposed. Firstly， the explosion action is simulated by ALE fluid-solid coupling method， and the impact load distribution and history on the surface of whole structure are obtained; Then， steel frame model is established， and study on dynamic response under explosion load is conducted. The result shows that the explosion load has weak transitivity and locality in frame. Finally， a simplified model of steel beam-to-column joints is proposed. The dynamic response of simplified model under explosion load is carried out. The result shows that the displacement， velocity and acceleration of the simplified model in the key points are in agreement with the overall model. It is reasonable and reliable to study the performance of the beam-to-column joints under blast load with simplified model.

Key words blast loading; fluid-solid coupling; simplified model; steel joint; LS-DYNA

近年来恐怖袭击时有发生，导致房屋倒塌，造成大量的人員伤亡与财产损失。针对建筑的恐怖袭击中，汽车炸弹是最常用的手段。

爆炸导致的结构倒塌破坏分析主要采用试验研究、理论分析方法和有限元模拟分析方法。由于爆炸危险性较高，相关试验研究较少，而理论研究难以全面再现复杂的爆炸行为，有限元模拟成为主要的研究手段。高超等[1]采用缩尺模型试验与数值模拟对比的方法进行了钢筋混凝土框……