多水准位移能力谱抗震设计方法

Displacement-Based Multiple Performance Objective Seismic Design on Capacity Spectrum Method

在改进能力谱方法和多水准抗震设计理念的基础上,提出了基于位移能力谱的多水准抗震设计方法.利用位移能力谱方法,获得了结构在不同抗震设防水准下结构的位移需求和延性系数,并构造出多水准需求谱.从多水准需求谱上得到多个基于位移抗震设计的控制点,最终构造出结构设计能力基准曲线.基于结构设计能力基准线对结构进行设计,能使结构同时满足'小震不坏'的弹性位移需求和'中震可修'及'大震不倒'的弹塑性位移需求.根据一个单自由度桥墩抗震设计的全过程,说明了基于位移的多水准抗震设计方法不仅能够满足各个设防水准的需求,而且根据该方法设计的结构具有最优的经济性.

Combining the improved capacity spectrum method with seismic design theory of multiple performance objectives, a seismic design method of displacement-based capacity spectrum with multiple performance objectives was proposed. Using the proposed seismic design method, displacement demands and ductility coeffi- cient of structures under different seismic fortification levels were obtained, and a multi-level demand spectrum was also formed. Based on this multi-level demand spectrum, multiple key points were gained, which formed a capacity curve for structural design. Structural design based on the proposed curve can satisfy both elastic displacement demands of minor earthquake and elastic-plastic displacement demands. Finally, the whole seismic de- sign process of a SDOF pier was analyzed. It has been proved that the proposed method can satisfy the displacement demands of different seismic fortification levels, and can make the structures designed in this method more economical.