钢框架-混凝土核心筒结构框架地震设计剪力标准值研究

Study on Seismic Design Shear Force for Frame of Steel Frame-concrete Core Wall Structures

为研究双重体系钢框架-混凝土核心筒结构的框架设计地震剪力标准值,对20个钢框架-混凝土核心筒结构模型进行了静力弹塑性分析。从承载力、结构失效模式和框架破损程度三个方面评价20个计算模型的抗震能力。根据推覆分析结果,提出了如下设计建议:8度抗震设防时钢框架-混凝土核心筒结构的刚度特征值λ大于0.65,各层框架的设计地震剪力标准值不小于本层总剪力的18%和不小于框架-核心筒结构计算得到的地震剪力的1.2倍(加强层和顶层的剪力可不小于框架-核心筒结构计算得到的地震剪力),框架角柱轴压比不大于0.5。算例表明,符合建议的钢框架-混凝土核心筒结构,在地震作用时不会出现不合理的破坏形态。

To study seismic design shear force for steel frame of steel frame-reinforced concrete core wall structures, static elasto-plastic analysis （pushover analysis） of 20 structural models was conducted, The earthquake resistant capacity of the 20 structure models is evaluated by three aspects, i.e. , load-carrying capacity, structural failure mode and seismic damage index under structural failure state. It is recommended that for steel frame-reinforced concrete core wall structures the structural stiffness characteristic value should be larger than 0.65, the standard value of seismic design shear force of the steel frame should not be less than 18 % of the total storey shear and should not be less than 1.2 times of the frame shear obtained by analysis of steel frame-RC core wall structure （for the strengthen storey and the top storey, should not be less than the frame shear obtained by analysis of steel frame-RC core wall structure）, the axial force ratio of comer steel columns should not be larger than 0.5. It is demonstrated by a calculation example that under earthquake excitations un-excepted failure mode would not occur for steel frame-RC core wall structures which satisfy the above requfrements.