基于地震损失风险钢筋混凝土框架结构弯矩增大系数评估  

EVALUATION OF MOMENT MAGNIFYING COEFFICIENTS OF RC STRUCTURES BASED ON THE SEISMIC RISK ASSESSMENT METHOD

作　　者：王树和 张举兵 

机构地区：[1]北京科技大学土木与资源工程学院,北京100083

出　　处：《工程力学》2018年第3期132-140,共9页Engineering Mechanics

摘　　要：损失是表征结构性能的综合指标。为了从损失风险的角度评估现行抗震规范钢筋混凝土框架弯矩增大系数的取值,基于地震风险评估框架FEMA P-58,给出了基于结构整体易损性分析的地震损失计算方法。设计了4个弯矩增大系数分别为1.1、1.3、1.5、1.7的钢筋混凝土框架结构,采用增量动力时程分析方法,得出了结构的易损性曲线和易损性矩阵,按照地震烈度概率模型,给出了所在场地各种烈度地震发生的概率,计算了每个结构在50年和1年内的经济损失和人员伤亡损失。结果表明,地震损失风险随强柱弱梁系数增大而减小,50年总经济损失比介于0.08~0.12,人员损伤率介于4.85×10-4~1.12×10-3。按照目前规范取值设计的结构地震损失风险处于可接受范围内。Loss 1s a comprehensive index ot structural selsImc perlormance. In orcter to evaluate me rauonallty of moment magnifying coefficients of concrete frame structures in the current national seismic code, a method of seismic loss calculation was proposed. The method was based on structural fragility analysis and the loss calculation frame FEMA P-58, and was from the viewpoint of seismic loss risk. Four reinforced concrete frame structures with moment magnifying coefficients of 1.1, 1.3, 1.5, 1.7 were designed. The fragility curves and fragility matrixes were obtained by using the incremental dynamic analysis. According to the seismic intensity probability model, the probability distribution of various seismic intensity of the site was given. The 50-year and annual monetary and human losses of every structure were calculated. The results indicate that the seismic loss risk will decrease with the increase in moment magnifying coefficient. The 50-year total monetary loss ratio ranges between 0.08 and 0.12. The human loss ratio ranges between 4.85×10^-4 and 1.12×10^-3. The seismic loss risk is acceptable if the structure is designed to the current national design code.

关 键 词：混凝土框架 弯矩增大系数 地震风险 损失 易损性曲线 

分 类 号：TU375.4[建筑科学—结构工程]