【作者】 侯耿峰；

【导师】 熊进刚；

【作者基本信息】 南昌大学 ， 结构工程， 2010， 硕士

【摘要】 目前,结构的连续倒塌已成为严重威胁公共安全的重要问题,由于恐怖袭击、火灾、飓风、施工缺陷、人为错误、煤气爆炸等原因所导致的连续倒塌事故越来越多。1968年英国Ronan Point公寓倒塌事件发生以后,国外许多工程师和学者在该领域开展了研究,提出了相应的抗连续倒塌设计的方法和规范,例如拉结设计和备用荷载路径分析等方法。而我国在这方面的研究比较欠缺,现行规范还未涉及,还有大量的工作需要开展。结构的延性是防止建筑连续倒塌的重要因素,对该方面的研究具有重要意义。本文介绍了国内外连续倒塌的研究现状,对国外前沿成果进行了描述,并对国外抗连续倒塌相关规范做了总结。按照我国钢筋混凝土设计规范中的材料应力应变关系以及相关假定,推导了梁截面屈服曲率、极限曲率和塑性铰转角的计算公式。采用通用有限元程序ANSYS线性静力分析和非线性静力分析,对实验室一空间框架模拟底层中柱失效的连续倒塌试验进行了计算分析,分析结果基本吻合,验证了软件分析的正确性,同时讨论了连续性倒塌在ANSYS实现过程中所存在的问题。接着按照美国GSA中的有关规定,对8层的非抗震设计的原型框架进行抗连续倒塌性能评估,考虑长边中柱、短边中柱、角柱和内柱失效四种工况。针对抗连续倒塌需要,讨论了梁截面塑性铰转动能力要求,提出了非抗震设计框架的延性要求及相应措施。最后,对本文研究工作所得到的结论进行总结并对今后工作做了展望。更多还原

【Abstract】 Currently, the progressive collapse of the structures has become a serious threat to public safety. There are more and more structure progressive collapse caused by unexpected incidents as terrorist attack, fire, hurricane, constructional deficiency, human error and gas explosion. Since the partial collapse of the Ronan Point apartment building in 1968, engineers and reaserchers begin to pay more attention to the prevention of progressive collapse.Many design codes and methods for preventing progressive collapse have been developed, including the Tie Force and Alternate Load Path methods. However, researches on progressive collapse in our country are still insufficient. Until now, the codes criteria about the resistance of progressive collapse had not been provided. It is important to study the ductility of structures, for it is a major facor for preventing the progressive collapse.In this paper we reviewed the state of progressive collapse prevention home and abroad, and summaried the relevant design specifications for structure progressive collapse resistance. Based on the stress-strain relationship of steel and concrete and basic assumptions in designing code for concrete structures in our country, calculation formula of section yield curvature, section ultimate curvature and plastic rotation are deduced. The software ANSYS is used to analyze a RC model frame structure in a progressive collapse experiment.The analysis includes linear static procedure and nonlinear static procedure.The results prove the effectiveness of the programme. Some questions about ANSYS simulation are discussed. Then a performance evaluation of structure processive collapse resistance, based on the design procedure prescribed in GSA, is applied to an eight-story typical frame of none sesmic design. The frame is designed according to the current China desigining codes. Four different cases are considerd. In each cases, one column in particular location is removed These columns are the middle column of the long side of the building, the middle column of the short side of the building, the corner column and the internal column repectively.Addtionally, the requirement for plastic rotational capability to resist progressive collapse is analyzed. Strategies and measures to ensure a ductile structure of none sesmic design are proposed. Finally, the conclusions of this paper are summarized and the prospect of further studies is discussed.更多还原