基于IDA方法的RC框架结构倒塌与残余位移分析

发布时间：2018-04-24 12:30

本文选题：IDA方法 + RC框架结构　；参考：《苏州科技大学》2017年硕士论文

【摘要】：发生地震时,若RC框架结构的变形到达倒塌极限时,就会发生倒塌破坏。近年来钢筋混凝土框架结构倒塌失效准则有很多,但在实际应用时如何选择倒塌判定准则没有定论,而且建筑物的倒塌是造成人员伤亡和财产损失的主要原因。因此,对RC框架结构建立一个较为准确的倒塌失效准则就变得尤为重要。基于此,本文引入增量动力分析方法,对钢筋混凝土框架结构在地震作用下的倒塌进行了深入的研究。主要工作及结论如下:(1)对国内外RC框架结构倒塌失效准则进行总结并得出六种倒塌失效准则,分别为基于强度、变形、能量、变形和能量双参数、刚度和IDA方法失效准则。选择其中的基于IDA方法和变形的失效准则进行倒塌对比分析。(2)在进行增量动力分析之前,考虑到所选地震记录反应谱平台段与场地的卓越周期Ts的影响,而根据反应谱的两个频率段选取10条地震波,运用SeismoSingnal地震动分析软件确定Sa(T1,5%),最后运用huntfill不等步调幅原则对其进行调幅。采用SAP2000有限元软件建立一个十层三跨RC框架分析模型并对其中一榀进行一系列弹塑性时程分析,把得到的IM和DM连接成IDA曲线并利用“折半取中”的方法得到倒塌状态点。(3)计算出建筑结构倒塌状态点处对应的调幅系数,对地震记录进行调幅后并再次进行弹塑性时程分析;然后在分析时程中找出层间位移角达到变形限值1/50时及最后时刻出铰图,对梁柱的出铰情况进行分析总结得出:基于变形的倒塌失效准则有低估结构抗倒塌能力的风险并且IDA准则比变形准则较低的评价了结构的损伤。(4)定义了残余层间位移角的概念,并把其作为结构损伤指标运用在IDA分析中。通过与结构损伤指标为层间位移角的IDA倒塌分析进行对比得出:后者对结构抗倒塌性能的评估大于前者,而前者更为敏感。(5)通过运用不同结构损伤指标的IDA方法对结构进行易损性分析并对易损性曲线进行对比中发现DM为残余层间位移角进行IDA分析得到的易损性曲线对地震作用下倒塌风险的评估偏于保守,适合于一些重要性更高的结构。
[Abstract]:When an earthquake occurs, if the deformation of RC frame structure reaches the collapse limit, it will collapse and destroy. In recent years, there are many collapse failure criteria for reinforced concrete frame structures, but how to choose collapse criteria in practical application is not conclusive, and the collapse of buildings is the main cause of casualties and property losses. Therefore, it is very important to establish a more accurate collapse failure criterion for RC frame structure. Based on this, the incremental dynamic analysis method is introduced to study the collapse of reinforced concrete frame structures under earthquake. The main work and conclusions are as follows: (1) the collapse failure criteria of RC frame structures at home and abroad are summarized and six collapse failure criteria are obtained, which are based on strength, deformation, energy, deformation and dual parameters of energy, stiffness and IDA method. A comparative collapse analysis based on IDA method and deformation-based failure criterion is selected. Before the incremental dynamic analysis is carried out, the effects of the selected seismic response spectrum platform segment and the site excellent period ts are taken into account. According to the two frequency bands of the response spectrum, 10 seismic waves are selected, and the SeismoSingnal ground motion analysis software is used to determine the huntfill T1 / 5. Finally, the huntfill principle of unequal step amplitude is used to modulate the amplitude. A 10-story three-span RC frame analysis model was established by using SAP2000 finite element software, and a series of elastic-plastic time-history analysis was carried out on one of them. The obtained IM and DM are connected to the IDA curve and the collapse state point is obtained by the method of "half-fold".) the amplitude modulation coefficient at the collapse state point of the building structure is calculated, and the amplitude modulation of the seismic record is carried out and the elastic-plastic time-history analysis is carried out again. Then, in the analysis process, when the displacement angle between the floors reaches the deformation limit of 1 / 50 and at the last moment, the hinge diagram is found. From the analysis of Liang Zhu's hinge condition, it is concluded that the collapse failure criterion based on deformation has the risk of underestimating the collapse resistance of the structure and that the IDA criterion is lower than the deformation criterion in evaluating the damage of the structure. (4) the concept of the displacement angle between the residual layers is defined. It is used as structural damage index in IDA analysis. By comparing with the IDA collapse analysis with the structural damage index as the interstory displacement angle, it is concluded that the evaluation of the latter for the collapse resistance of the structure is greater than that for the former. The former is more sensitive. 5) by using the IDA method of different structural damage indexes to analyze the vulnerability of structures and compare the vulnerability curves, it is found that DM is the vulnerability curve obtained by IDA analysis of residual interlayer displacement angle. The assessment of the risk of collapse due to earthquake is conservative. Suitable for some of the more important structures.
【学位授予单位】：苏州科技大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TU375.4

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