爆炸荷载作用下钢框架结构连续倒塌分析  

Numerical analysis on damage and collapse process of steel frame structures under blast loads

作　　者：丁阳[1] 汪明[2] 李忠献[1] 

机构地区：[1]天津大学滨海土木工程结构与安全教育部重点实验室,天津300072 [2]天津大学建筑工程学院,天津300072

出　　处：《建筑结构学报》2012年第2期78-84,共7页Journal of Building Structures

基　　金：国家自然科学基金重点项目(50638030);国家自然科学基金面上项目(51178036);国家科技支撑计划重点项目(2006BAJ13B02);天津市应用基础和前沿技术研究计划重点项目(08JCZDJC19500);天津市科技支撑计划项目(06QTPTSF05600)

摘　　要：传统数值方法模拟建筑结构在爆炸荷载作用下的结构响应和连续倒塌时,具有计算模型复杂、计算量大的特点,实际应用价值不大。基于将爆炸荷载作用下结构响应分析分两步进行的数值模拟方法,利用非线性显式动力分析软件AUTODYN的Remap技术模拟爆炸波在空气中的传播过程,利用压强测点记录结构构件表面的爆炸压强时程曲线;建立结构精细化有限元模型,并将上一步记录的爆炸压强时程曲线施加于结构构件,利用LS-DYNA显式求解器分析结构在爆炸荷载作用下的动态响应和倒塌过程。将该方法应用于某钢框架结构在爆炸荷载作用下的动态响应和连续倒塌分析。结果表明:钢框架结构具有较好的抗爆性能,在发生1 000 kg TNT当量及以下规模的室外爆炸时,主体结构能够保证安全;在发生1 500 kg TNT当量及以上大规模爆炸时,发生次梁塌落等局部破坏,亦可能发生结构连续倒塌。The traditional numerical methods for simulating the dynamic response and progressive collapse of entire structures require complicated modeling work and extremely time-consuming calculation, resulting in their rare application. In this paper, a new method for the numerical analysis of entire structural model is proposed, which is directly employed to analyze the dynamic response and damage patterns of steel frame structures subjected to blast loads. According to the new method, the simulation process is divided into two steps. Firstly, the propagation of blast wave in air is simulated by the Remap tool of AUTODYN. The numerical gauges are used to record the pressure time history on the surfaces of structural members, e.g. columns and beams. Secondly, a refined finite element model of steel frame structure is created, and the blast load is applied on the surfaces of members according to the measured data in the first step for further analysis of structural response and damage procedure using the explicit solver of LS- DYNA. The whole simulation of structural response of a typical steel frame structure caused by blast load is carried out. The numerical results show that the steel frame structure is capable of resisting blast load, which is adequate to survive a medium-scaled （ up to 1 000 kg equivalent of TNT charge） out-door explosion. Severe progressive collapse or local damage as downfall of secondary beam is likely to be induced by a huge-scaled blast load case （more than 1 500 kg equivalent of TNT charge）.

关 键 词：钢框架结构 爆炸荷载 连续倒塌 数值分析 精细化模型 抗爆性能 

分 类 号：TU391[建筑科学—结构工程] TU312.1