某超限高层结构抗震分析与设计

Seismic analysis and design of a transfinite high-rise structure

某LOFT公寓高层建筑结构采用部分框支剪力墙结构体系,结构存在扭转不规则、局部楼板不连续和竖向构件不连续等不规则项,按《高层建筑混凝土结构技术规程》(JGJ3-2010)规定定性为超限高层结构。本文根据多项结构不规则情况,按《广东省高层建筑混凝土结构技术规程》确定相应抗震性能目标,对结构分别在小震、中震、大震作用下进行各项性能指标分析;针对LOFT公寓的建筑特点,对结构分别选择分层结构建模和降梁式结构建模两种方法进行对比分析;鉴于结构局部楼板不连续,对各层楼板的应力状态进行详细的有限元分析;因结构存在大量转换体系、竖向构件不连续,为验证转换梁能否满足正常使用和承载能力极限状态的要求,对转换层的转换梁进行荷载组合作用下详细的有限元分析。研究结果表明,采取抗震超限加强措施,可满足规范性能设计要求。

The high-rise building structure of the LOFT apartment adopts partial frame-supported shear wall structure system.The structure has irregularities such as torsion irregularity,local floor slab discontinuity and vertical member discontinuity.According to the national Technical specification for concrete structures of tall building(JGJ 3-2010),it is classified as an over-limit high-rise structure.In this paper,according to the irregularities of many structures,the corresponding seismic performance target is determined according to Technical Regulations for Concrete Structures of High-rise Buildings in Guangdong Province,and the performance indexes of small,medium and large earthquakes are analyzed.According to the architectural characteristics of the LOFT apartment,two methods of structural modeling and dropping beam structure modeling for structural modeling are compared and analyzed.In view of the local floor discontinuity in the size of structural slabs,the detailed finite element analysis of the stress state of each floor is conducted.Due to the large number of conversion systems in the structure and the discontinuity of the vertical members,in order to verify that the transfer beam can meet the requirements of normal use and ultimate state of bearing capacity,a detailed finite element analysis of the transfer beam under combined load is carried out.According to the above research results,it is shows that the performance design requirements of the code can be met by adopting the seismic overrun strengthening measures.