高耸钢筋混凝土烟囱结构地震易损性分析  

Seismic fragility analysis for high-rise reinforced concrete chimney

作　　者：周长东[1] 曾绪朗 赵锋[2] 周浩[2] 

机构地区：[1]北京交通大学土木建筑工程学院,北京100044 [2]中冶建筑研究总院有限公司,北京100088

出　　处：《地震工程与工程振动》2016年第2期173-181,共9页Earthquake Engineering and Engineering Dynamics

基　　金：国家自然科学基金面上项目(51478033;51178029)~~

摘　　要：为了分析高耸钢筋混凝土烟囱结构的抗震性能,本文选取240 m高的钢筋混凝土烟囱作为研究对象;采用Open Sees程序,基于分布塑性的纤维梁柱单元,建立了相应结构的非线性有限元三维分析模型。为充分考虑地震动的不确定性,根据谱相容性原则,选择21条真实的地震动记录,进行增量动力分析。分别以截面曲率延性系数和地面加速度峰值作为结构地震需求参数和地震动强度参数,结合非线性增量动力分析所获得的结构地震响应,基于对数正态分布假设,通过回归分析建立了结构的概率地震需求模型。以钢筋和混凝土的材料应变水平为基础,通过95个截面的分析结果定义了4个损伤状态限值;最终形成了钢筋混凝土烟囱结构的地震易损性曲线,对烟囱结构的易损性能进行了评估和分析。分析结果表明:该烟囱结构在多遇地震、基本地震及罕遇地震下发生轻微损伤的概率分别为0、20%和75%,而发生中等损伤、严重损伤及完全损伤的概率基本为0。本文对于地震易损性的研究结果,可为钢筋混凝土烟囱结构的抗震设计、地震风险评估及灾后加固提供理论依据。To analyze the seismic behavior of high-rise RC chimney,this paper selected one 240 high RC chimney as the research object. On the basis of distributed plastic fiber beam-column element,a detailed three-dimensional structural nonlinear analytical model is developed using the finite element software Open Sees. In order to consider the uncertainties in ground-motion realizations,according to the principle of spectral compatibility,21 natural ground motion records are selected as the basis of incremental dynamic analysis. The peak ground acceleration and curvature ductility ratio have been selected as the intensity measure and structural seismic demand parameters,respectively. Based on lognormal assumptions,nonlinear incremental dynamic analysis is then performed for the case study RC chimney and statistically analyzed to build the probabilistic model of the seismic demand. According to concrete and longitudinal reinforcement strain levels,four damage limit states,named as the light,moderate,extensive and complete damage,were defined in terms of the analysis results of 95 sections. Then the fragility curves are developed for the RC chimney at various damage states and its vulnerability assessment and analysis are conducted. The study indicates that for frequent earthquake,basic earthquake and rare earthquake,the probabilities of exceeding the light damage state are around 0%,20% and 75%,respectively; while the probabilities ofexceedance corresponding to moderate,extensive and complete damage states are approximately zero. The results of the fragility analysis developed in this paper for the RC chimney would be helpful for seismic design,seismic risk assessment and seismic retrofit of RC chimney structures.

关 键 词：高耸结构 钢筋混凝土烟囱 地震易损性 增量动力分析 抗震性能 

分 类 号：TU279.742[建筑科学—建筑设计及理论] P315.91[天文地球—地震学]