中国国际丝路中心超高层结构设计与关键技术

Structural design and key technology of China International Silk Road Center super high-rise building

中国国际丝路中心超高层建筑总高度498 m,位于陕西省西安市,抗震设防烈度8度,该结构的侧向变形和承载力均由地震作用控制。为解决结构侧向刚度不足的问题,设置了伸臂桁架加强层,然而传统伸臂桁架往往会造成结构刚度和承载力突变等问题。为此,采用基于刚性伸臂和黏滞阻尼伸臂的组合伸臂桁架技术,研究刚性伸臂桁架和黏滞阻尼伸臂桁架在结构中的较优布置位置和实际效果,从结构指标、结构耗能、构件受力及经济性等方面进行了综合对比。提出了在结构上部两个避难区布置黏滞阻尼伸臂桁架,在结构下部两个避难区布置刚性伸臂桁架的布置方式。从结构响应和结构损伤方面,分析了结构在不同水准地震作用下的抗震性能,并对结构伸臂桁架关键节点进行了有限元分析。结果表明:通过采用组合伸臂桁架技术,可使结构耗能机制得到改善,结构地震响应和构件损伤得到降低,且伸臂桁架安全可靠。

The height of the super high-rise building-China International Silk Road Center is 498 m.The building is located in Xi’an Shaanxi province,where the seismic intensity is 8 degree,and the lateral deformation and load bearing capacity of the structure are both controlled by the seismic load.In order to solve the problem of insufficient lateral stiffness of the structure,the use of an outrigger truss strengthened storey was considered.However,the traditional outrigger truss often leads to an abrupt change in the stiffness and bearing capacity of the structure.To address this issue,the hybrid outrigger technology involving both rigid and viscous damping outriggers was applied to the building design.The optimum position and efficiency of the outrigger truss arrangement were investigated through calculation and analysis,taking into consideration the structural index,structural energy dissipation,member stress and economic aspects.The layout of viscous damping outrigger truss in the upper two refuge areas and the rigid outrigger truss in the lower two refuge areas was proposed.From the aspects of structural response and structural damage,the seismic performance of the structure under different levels of earthquake was analyzed,and the finite element analysis of the key joints of the outrigger truss was carried out.The results show that,by using the hybrid outrigger truss technique,the energy dissipation mechanism of the structure can be improved,the seismic response and member damage can be reduced,and the outrigger truss is safe and reliable.