预应力巨型支撑-钢框架结构中钢框架基础抗侧刚度研究

Basic Lateral Stiffness of Steel Frame in Prestress-Mega-Braced Steel Frame Structure

目的研究新型结构形式———预应力巨型支撑-钢框架结构体系中钢框架所须具有的基础抗侧刚度以及钢框架与拉索的最佳匹配范围.方法理论分析后采用SAP2000建立不同结构尺度的二维结构模型,变化框架相对抗侧刚度,进行几何非线性有限元分析.结果钢框架所须具有的基础抗侧刚度大致为2.5倍的层间位移角设计目标值所对应的抗侧刚度;当钢框架的抗侧刚度大致为2倍的层间位移角设计目标值所对应的抗侧刚度时,配以相应的巨型支撑后,预应力巨型支撑-钢框架结构的整体用钢量最省.结论预应力巨型支撑-钢框架结构体系中,钢框架与拉索各提供设计要求的抗侧刚度值为50%时,技术经济效果最佳.

The aim is to obtain the basic lateral stiffness of steel frame and the optimum matching of steel frame and cable in prestress-mega-braced steel frame structure. Following the theoretical analysis, the geometric nonlinear finite element analysis with SAP2000 considering different structural dimension was presented. The results indicate that the basic lateral stiffness of steel frame should be roughly 40% of the lateral stiffness which corresponding to the design story drift angle target value, and the total structural steel is minimum when the lateral stiffness of steel frame is roughly 50% of the lateral stiffness which corresponding to the design story drift angle target value. So for prestress-mega-braced steel frame structure, it is optimal that the steel frame and the cable have the same structural lateral stiffness.