基于增量理论的震损结构抗震性能评估方法

为了准确评估地震受损结构的抗震性能,基于模态弹塑性理论,提出了一种考虑结构动力特性的增量静力弹塑性分析方法(IDPA)。该方法结合动力时程分析方法和静力弹塑性分析方法的优点,对传统Pushover分析方法中结构在地震作用下的顶点目标位移确定方法进行了改进,同时考虑高阶振型影响,改进了传统方法中侧向力的加载模式;确定了建立地震受损构件抗震性能分析模型的方法,给出了IDPA方法针对地震受损结构抗震性能评估的实施步骤。将改进方法应用于某10层受损钢筋混凝土框架结构的抗震性能评估中,对比分析了传统方法和IDPA方法计算结果与时程分析计算结果的差异。计算结果表明,IDPA方法能够有效模拟损伤结构在地震作用下的真实反应,也能体现损伤结构再次遭遇地震作用时的非线性行为,特别是对于高阶振型影响明显的结构,IDPA方法能够获得较理想的评估结果。

Seismic performance evaluation method of earthquake damaged structures based on incremental theory

To better assess the seismic performance of damaged structures, a new incremental dynamic pushover analysis (IDPA) method with dynamic characteristics of structures was presented based on the theory of modal elastic-plasticity. This method combined the advantages of dynamic time history analysis and push-over analysis. In the IDPA method,the top target displacement under the earthquake action was improved,and the lateral load pattern was also improved by considering the influence of high modes. Then,the principle of seismic analysis model of earthquake damaged structures was established, and implementation steps of IDPA method for seismic performance evaluation of earthquake damaged structures were given. The improved method was applied to the seismic performance evaluation of a ten story reinforced concrete frame structure, and then the differences between the result traditional method and the IDPA method and the result of time history analysis calculation were compared and analyzed. IDPA method can effectively simulate the real response of the damaged structures under earthquake. The results show that the IDPA method can efficiently simulate the seismic response of the structure under earthquakes and can also embody the nonlinear behavior of the damaged structure during the subsequent earthquakes.