基于易损性的RC空间框架填充墙结构连续倒塌能力分析

为研究填充墙对RC空间框架抗竖向连续倒塌能力的影响，对一栋6层双跨RC框架结构采用OpenSees有限元软件进行了建模，利用集中塑性的beamWithHinges单元模拟填充墙的性能。考虑到结构的不确定性，在有限元模型的基础上采用改进的拉丁超立方体抽样法获得了性能不同的100个纯框架结构和100个框架填充墙结构，并采用PDA方法和竖向IDA方法对取得的样本进行了易损性分析和对比。分析结果表明：填充墙提高了框架结构的抗倒塌能力，发生连续倒塌概率相同的情况下，框架填充墙结构的承载能力要比纯框架结构的高10%~20%。此外，两种分析方法对纯框架结构的抗连续倒塌能力分析差别较小，而对于带填充墙的框架结构，PDA方法计算结果则偏于保守。

Fragility-based progressive collapse capacity analysis of RC frame structures with infilling walls

To evaluate the impact of infilling walls on the progressive collapse of the reinforced concrete frames structure, the OpenSees was used to model a two-bay and six-story reinforced concrete frame structure，in which the infill wall was simulated by the beamWithHinges element. Considering the uncertainties of the structure, one hundred RC bare frame samples and one hundred RC frame samples with infill walls were obtained by the improved Latin hypercube sampling (LHS) method on the basis of the finite element model. Static Pushdown analysis (PDA) and vertical incremental dynamic analysis (IDA) methods were performed on the samples to analyze the fragility of the structure. The results show that infill wall improves the collapse resistance of the frame structure. At the same level of progressive collapse probability, the resistance of the frame infilled with walls is 10% to 20% higher than that of the bare frame. In addition, two analysis methods would generate little effect on collapse resistance capacity of bare frame,while compared with IDA method, the PDA method tends to be conservative for the analysis of the frame structure with the infilling walls.