直接基于位移的橡胶支座隔震结构性能设计方法

将隔震结构简化为等效单自由度系统(ESDOF),隔震层采用铅芯橡胶支座,应用直接基于位移的性能设计方法(DDBD)分析隔震结构。重点讨论多自由度隔震结构(MDOF)向单自由度等效体系的转化方法,分析体系等效阻尼比、目标位移与等效质量。根据《建筑抗震设计规范》建立了位移反应谱,改进基于位移的性能设计方法的流程。设计高烈度区某隔震工程,假定各楼层的目标位移与体系等效阻尼比,通过性能设计流程最终得出各楼层的剪力分布;对设计的结构进行了时程分析校核,表明方法不但简单有效而且满足工程设计精度要求,可用于隔震结构的初步设计。

Direct displacement-based design method for seismic isolation structures with rubber bearings

The seismic isolation structure was converted into an equivalent single degree of freedom(ESDOF) system.Lead rubber bearings were used in the isolation layer.The direct displacement-based design(DDBD) method was introduced to design seismic isolation structures.Focused on the transformation process of the multi-degree of freedom model(MDOF) to ESDOF of the base isolated structure,compositions of equivalent damping ratio,target displacement and equivalent mass of the system were analyzed.Based on the revision of slope adjustment factor and damping adjustment factor for the response spectrum in Code for Seismic Design of Buildings,the displacement response spectrum was established and the design procedure of the DDBD method was improved.The method was used to design a seismic isolation structure in high intensity zone by assuming the target displacement of each floor and the damping ratio of the system,the distribution of storey shear was finally obtained through the design procedure.The designed structure was checked by time history analysis.The results showed that the method was simple and effective,and had certain accuracy.It was suitable for the preliminary design of the seismic isolation structure.