某异型多塔连体高层结构巨震下抗震性能与极限承载力研究

Study on seismic performance under very rare earthquake and ultimate bearing capacity of a special-shaped multi-tower-connected high-rise building

某异型多塔连体高层结构,采用带悬挑体的钢结构支撑筒连体结构,由三个钢结构支撑筒体及悬挑(连体)部分组成,三个钢结构支撑筒体在不同高度两两刚性相连,且存在多处大跨度悬挑,结构落地面积小。针对这类结构的抗震性能、稳定极限承载力,开展专项研究。选择7组地震波,进行7度罕遇地震下的动力弹塑性分析和性能评价;在此基础上,增大地震作用水平至8度、9度罕遇地震,进行结构的抗震性能验证,并与7度罕遇地震下分析结果进行比较,考察结构整体承载力与刚度退化的过程。同时采用静力非线性分析的方法,在考虑几何非线性和材料非线性的基础上,对结构进行水平荷载作用下的极限承载力分析。结果表明:地震作用下结构破坏顺序符合设计预期,具有抵御9度罕遇地震的能力。

A special-shaped multi-tower-connected high-rise structure adopts steel structure support cylinder connected structure with cantilevered body, which is composed of three steel structure supported cylinders and cantilevered(connections) parts. The three steel structure support cylinders are rigidly connected two by two in pairs at different heights, with multiple large-span cantilevered bodies and relatively small bottom support area. Special research was conducted on the seismic performance and the ultimate bearing capacity of such structures. Seven groups of seismic waves were selected to conduct elastic-plastic time-history analysis and performance evaluation under 7-degree rare earthquakes;on this basis, the earthquake action level to 8-degree and 9-degree rare earthquakes were increased to verify the seismic performance of the structure, the analysis results were compared under 7-degree rare earthquake, and the overall bearing capacity and stiffness degradation process of the structure were investigated. At the same time, on the basis of considering geometric nonlinearity and material nonlinearity, the ultimate bearing capacity analysis of the structure under horizontal load were carried out by the method of Pushover analysis. The results show that the failure sequence under the earthquake action is in accordance with the design expectations, and the structure has the ability to withstand 9-degree rare earthquakes.