基于耐震时程法的锈蚀RC框架结构抗地震倒塌能力评估  

Seismic collapse capacity assessment of corroded RC frames using the endurance time method

作　　者：何子涵 代旷宇 吕大刚[1] 于晓辉 HE Zihan;DAI Kuangyu;LV Dagang;YU Xiaohui(School of Civil Engineering,Harbin Institute of Technology,Harbin 150090,China;School of Water Conservancy and Civil Engineering,Zhengzhou University,Zhengzhou 450001,China;College of Civil Engineering and Architecture,Guilin University of Technology,Guilin 541004,China)

机构地区：[1]哈尔滨工业大学土木工程学院,黑龙江哈尔滨150090 [2]郑州大学水利与土木工程学院,河南郑州450001 [3]桂林理工大学土木与建筑工程学院,广西桂林541004

出　　处：《地震工程与工程振动》2022年第6期129-135,共7页Earthquake Engineering and Engineering Dynamics

基　　金：国家自然科学基金项目(52078176,51778198,51678209)。

摘　　要：钢筋锈蚀会造成钢筋混凝土结构的抗震性能下降,使得结构在地震作用下更易发生倒塌。因此,有必要针对锈蚀钢筋混凝土结构开展抗地震倒塌能力评估。目前,增量动力分析(incremental dynamic analysis,简称IDA)方法被广泛用于结构的抗倒塌能力评估中。然而,IDA方法计算耗时多,计算效率较差。针对这一问题,文中采用耐震时程方法对锈蚀钢筋混凝土结构进行抗地震倒塌能力评估。以一栋按我国规范设计的钢筋混凝土框架作为研究对象,考虑未锈蚀,10%锈蚀率和20%锈蚀率3种工况的影响。分别采用耐震时程法和IDA方法得到了未锈蚀,10%锈蚀率和20%锈蚀率下钢筋混凝土框架结构的倒塌易损性曲线,并计算获得了结构的倒塌裕度比。研究结果表明:随着锈蚀率的提高,钢筋混凝土框架结构的倒塌裕度比会随之减小。将耐震时程法和IDA方法的分析结果进行对比,2种方法获得的结构倒塌易损性曲线和倒塌裕度比结果均吻合良好,说明耐震时程法可作为IDA方法的一种有效替代方法用于结构的抗倒塌能力分析。Reinforcement corrosion would degrade the seismic performance of reinforced concrete(RC)structures,leading more vulnerability of structures to collapse under earthquakes. Therefore,it is necessary to evaluate the seismic collapse capacity for the RC structures with corroded reinforcement. Currently,the incremental dynamic analysis(IDA)approach is widely used for the assessment of seismic collapse capacity of structures. However,it often costs numerous time and has low computational efficiency. To solve this problem,this study adopts the endurance time method to evaluate the seismic collapse capacity for corroded RC frames. For illustration,a typical RC frame is designed according to Chinese code as the study case. The corroded rates of zero,10% and 20% are considered.The endurance time method and IDA method are both used to calculate the seismic collapse fragility curves and collapse margin ratios for the corroded RC frames. The results show that collapse margin ratio decreases with the increase of corrosion rate. Make a comparison of the results by the endurance time method and IDA method. It is found that they yield similar resutes of the collapse fragility curves and collapse margin ratios. This reveals that the endurance time method could be an efficient replacement of IDA method for seismic collapse capacity assessment of structures.

关 键 词：地震抗倒塌能力 钢筋锈蚀 钢筋混凝土结构 耐震时程法 倒塌裕度比 

分 类 号：TU311[建筑科学—结构工程]