钢框架结构基于位移的抗震设计方法

Displacement-based seismic design method of steel moment resisting frame

与传统基于力的抗震设计方法相比,基于位移的抗震设计方法更易于实现基于性能的抗震设计。在若干文献的基础上,提出了一种钢框架结构基于位移的抗震设计方法。该方法建立在钢框架结构屈服位移可由几何尺寸确定的基础上,然后根据结构的性能水平确定其目标位移(即极限位移),计算相应的延性系数,采用相应的折减弹性谱,据此计算出结构的设计基底剪力,然后对钢框架结构进行刚度设计和承载力设计。算例分析表明,钢框架结构基于位移的抗震设计方法安全可靠,便于操作,而且还能够实现钢框架结构在不同性能水平下的抗震设计。

In contrast to the traditional method of force-based seismic design,the newly developed displacement-based seismic design will more easily fulfill the requirement of performance-based seismic design.According to lots of documents previously studied,a seismic design method is put forward based on displacement for steel moment resisting moment.This method is established in condition that the yield displacement of steel frame can be determined by its geometrical dimension;then the objective displacement（ultimate displacement）can be determined in light of performance level of the structure,and the corresponding coefficient of ductility can be obtained.Thereafter,the design base shear of steel frame structure can be calculated by the use of reduced elastic spectrum.Thus,the design of stiffness and capacity can be conducted on steel frame structure.The analysis of case study indicates that the displacementbased seismic design method addressed herein is of reasonable safety and reliability,and of operational convenience,which can still realize the seismic design of steel frame structure at different performance levels.