CFT框架-RC剪力墙结构基于一致倒塌风险的抗震设计研究

Research on uniform collapse risk-based seismic design of CFT frame-RC shear wall structures

我国CFT框架-RC剪力墙结构通常按照双重抗侧力体系进行设计。与一般RC框架相比,在相同竖向承载力条件下的截面尺寸和抗弯刚度较小,按双重抗侧力体系设计将影响结构的经济性能和建筑功能。因此,文章根据我国规范设计了典型的CFT框架-RC剪力墙双重抗侧力体系结构模型,采用一致倒塌风险的抗震设计方法中对单重抗侧力体系设计的要求,设计了相应的CFT框架-RC剪力墙单重抗侧力体系结构模型,并对比分析了单重和双重抗侧力体系在不同水准地震作用下的结构响应和罕遇地震结构倒塌概率和抗地震倒塌安全储备。结果表明,与双重抗侧力体系相比,单重抗侧力体系结构的地震响应和大震倒塌概率相近,均满足“大震不倒”抗震要求,而单重抗侧力体系的结构抗地震倒塌安全储备较大,且用钢量较少。

In general,the CFT frame-RC shear wall structures are designed according to the dual lateral-force resisting system.Compared to general RC frames,the dual lateral resistant design frames with the same vertical loading capacity have smaller sectional dimensions and bending stiffness.The design methodology of the dual lateral-force resisting system may affect the architectural functions and economic benefits.Therefore,the typical CFT frame-RC shear wall structures with the dual lateral-force resisting system are firstly designed by following the design codes of China in this work.Subsequently,the corresponding single lateral-force resisting structures are designed according to the uniform collapse risk-based seismic design methodology.The seismic responses and collapse probabilites of the major earthquakes for the single and dual lateral-force resisting systems are analyzed and compared.The results indicate that the seismic responses and collapse probabilities of the major earthquakes of the single and dual lateral-force resisting systems are similar.However,the single lateral-force resisting system exhibits better collapse resistance,safety performance and economic benefits.