爆炸荷载作用下钢筋混凝土框架结构连续倒塌分析方法比较研究

发布时间：2018-10-26 18:19

【摘要】：由恐怖袭击、意外爆炸等事件引发的结构关键承力构件破坏从而最终导致的结构连续坍塌，，在造成严重人员伤亡的同时，也带来了巨大的经济损失。2001年9月11日，美国纽约世贸中心大楼遭恐怖袭击而发生彻底倒塌，自此建筑结构的连续倒塌现象在世界范围内受到了广泛的关注，国内外学者相继开展了对建筑结构连续倒塌分析的研究。为了将研究的结果通用化，美国国防部于2005年出台了UFC4-023-03《建筑物抗连续倒塌设计规范》，并于2009年对规范进行了改进。规范中采用了替代传力路径法对结构的连续倒塌进行分析。该方法是先移除结构关键受力构件然后对剩余结构进行线性静力分析、非线性静力分析以及非线性动力分析，然而分析过程中并未考虑引起关键构件失效的原因。本文采用数值模拟法研究了由于爆炸荷载作用导致结构关键构件失效而引发的结构连续倒塌的情况，并与规范中的分析方法进行了比较研究。主要研究工作内容如下：（1）运用显式有限元动力分析软件LS-DYNA，建立了一个典型的四层两跨钢筋混凝土框架结构模型，对不同比例距离的爆炸荷载作用导致的仅结构底层中柱或仅结构底层边柱发生初始破坏的情况分别进行了数值模拟。（2）采用美国UFC规范中使用的替代传力路径法对相同的四层钢筋混凝土框架结构进行了线性静力分析和非线性动力分析。（3）将爆炸荷载作用下的数值模拟结果与采用规范中的替代传力路径法分析的结果进行对比，找出了该分析方法存在的不足，并对考虑爆炸荷载作用的结构抗连续倒塌分析设计方法的改进提出了设想。
[Abstract]:The destruction of key structural load-bearing components caused by terrorist attacks, accidental explosions, and so on, resulting in successive structural collapses, not only caused serious casualties, but also brought huge economic losses. On September 11, 2001, Since the complete collapse of the World Trade Center Building in New York, the continuous collapse of the building structure has been paid more and more attention in the world, and scholars at home and abroad have carried out the research on the continuous collapse analysis of the building structure one after another. In order to generalize the results of the study, the Department of Defense published the UFC4-023-03 Code for continuous collapse Design of buildings in 2005 and improved the Code in 2009. In the code, the method of alternative force transfer path is used to analyze the continuous collapse of the structure. In this method, the key structural members are removed first and then the residual structures are analyzed by linear static analysis, nonlinear static analysis and nonlinear dynamic analysis. However, the failure reasons of the key members are not considered in the process of analysis. In this paper, a numerical simulation method is used to study the continuous collapse of structures caused by the failure of key structural members caused by explosive loads, and a comparative study is made with the analytical methods in the code. The main research contents are as follows: (1) A typical four-story two-span reinforced concrete frame structure model is established by using explicit finite element dynamic analysis software LS-DYNA,. Numerical simulation is carried out for the initial failure of the middle column or the edge column of the bottom layer caused by the explosion load of different proportions. (2) the linear static analysis and nonlinear dynamic analysis of the same four-story reinforced concrete frame structure are carried out by using the alternative force transfer path method used in the American UFC Code. (3) the results of numerical simulation under explosive load are compared with those of the method of alternative force transfer in the code, and the shortcomings of the method are found out. The improvement of the design method of continuous collapse analysis considering the effect of explosion load is also put forward.
【学位授予单位】：天津大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TU375.4;TU312.3

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