RC框架结构基于构件损伤的抗震性能评估研究

张耀庭+杜晓菊+杨力

摘 要：首先根据钢筋混凝土柱的拟静力试验结果，探讨王东升的修正Park-Ang模型的适用性；然后基于构件层次的结构损伤指标为地震需求参数，对钢筋混凝土框架结构进行了基于IDA的易损性分析，并结合基于最大层间位移角的分析结果，探讨了结构基于损伤的抗震性能评估方法的可行性.结果表明：王东升提出的修正Park-Ang模型考虑了加载路径的影响，能较准确地反映首次超越破坏后累积损伤的发展过程，且总体上判别试件损伤状态的准确性相对较高；基于损伤的IDA能较好地反映整体结构及局部的损伤发展过程、结构的失效破坏机制，能准确地判别结构的薄弱环节，但结构损伤指标会产生超出1.0的情况，不能很好地体现损伤指标原始定义的基本含义；相较结构基于最大层间位移角的抗震性能评估结果，基于结构损伤的抗震性能评估方法综合考虑了结构的响应与自身的能力，更全面地评估了结构的性能水准，能预测结构在不同地震强度下各性能状态的失效概率.

关键词：钢筋混凝土框架；修正Park-Ang损伤模型；增量动力分析；易损性分析；柱拟静力试验

中图分类号：TU375 文献标识码：A

文章编号：1674-2974（2016）05-0009-13

Abstract：This paper study discussed the applicability of Park-Ang model modified by Wang based on the pseudo-static test results of reinforced concrete columns. The structural damage index based on the component level was selected， and both the incremental dynamic analysis and fragility analysis of the reinforced concrete frame were conducted. Additionally， the prediction by the modified method to evaluate the seismic performance in terms of the damage index of the RC frame was compared with the maximum inter-story drift ratio of the fragility analysis result. The analysis results show that the modified Park-Ang model that considers the loading path effect predicts well the cumulative damage process after the first damage， which discriminates the specimen damage status accurately， the damage development process， and the overall and local failure mechanism. Further， the weak links can be accurately distinguished. However， the damage index higher than 1.0 may be caused by using these methods， which cannot accurately reflect the basic meaning of the original definition. Compared with the maximum inter-story drift ratio， the seismic performance evaluation method using the damage index considers the structural response and properties. The modified method can be used to evaluate the structural performance more comprehensively and predict the failure probability of the structures under different earthquake loads.

Key words：reinforced concrete frame； fixed Park-Ang damage model； incremental dynamic analysis； fragility analysis； pseudo-static test of columns

随着基于性能的抗震设计理论与损伤模型研究的发展，通过损伤模型来量化结构性能指标，实现基于损伤的抗震性能评估方法将成为必然.目前，基于钢筋混凝土结构在地震作用下的两种破坏模式，国内外学者采用不同的响应参数建立了各种各样的损伤模型，包括基于变形、退化、能量、低周疲劳及其组合形式的损伤模型，但没有一个统一、普遍适用的损伤模型.其中，基于变形与能量的Park-Ang损伤模型在地震工程领域中得到较多的应用和研究，根据该模型的缺陷与不足，Kunnath[[1]、Kumar[[2]、Chai[[3]、欧进萍[[4]、牛荻涛[[5]和吕大刚[[6]等学者从不同角度对其进行了修正和改进.本文首先根据钢筋混凝土柱的拟静力试验结果，探讨王东升的修正Park-Ang模型[[7]的适用性.然后，以结构损伤指标为地震需求参数，对钢筋混凝土框架结构进行了基于IDA方法的易损性分析，并结合基于最大层间位移角的分析结果，探讨了结构基于损伤的抗震性能评估方法的可行性.