脉冲型地震下竖向不规则重力柱-核心筒结构的弹塑性地震响应

Research on the Elastic-Plastic Seismic Response of Vertical Irregular Gravity Column-Core Tube Structure Under Pulse-Like Ground Motions

研究了速度脉冲型地震作用和结构竖向不规则双重不利条件对结构弹塑性地震反应的影响。设计了20层和30层的新型重力柱-核心筒典型结构,通过改变底层刚度得到一系列竖向不规则结构。分别选取10条速度脉冲和10条非速度脉冲地震记录,采用CANNY软件对竖向不规则重力柱-核心筒结构进行弹塑性动力时程分析,研究速度脉冲效应和竖向不规则对结构弹塑性地震响应的影响规律。结果表明,速度脉冲地震下结构层间剪力、层间位移和倾覆力矩均明显高于非速度脉冲地震下的对应值;竖向不规则对结构弹塑性抗震需求影响显著,层间位移角随着竖向不规则比率的减小而增大,层间剪力和倾覆力矩则呈略微减小的变化趋势。建议在新型重力柱-核心筒结构设计中应考虑速度脉冲地震和结构竖向不规则的耦合影响。

A research has been conducted on the influence of velocity pulse type seismic actions on the elasticplastic structural seismic response,taking into consideration the dual adverse conditions of pulse-ground motions with a vertical irregularity.Based on the design of a new type of 20-and 30-story typical gravity column core tube structure,a series of vertical irregular structures can be obtained by changing the stiffness of the bottom story.With 10 velocity pulse and 10 non-velocity pulse seismic records selected respectively,an elastic-plastic dynamic time history analysis is conducted on the vertical irregular gravity column core tube structure by using CANNY software,with a further study on the influence of velocity pulse effect and vertical irregularity on the elastic-plastic seismic response of the structure.The results show that the inter-story shear force,inter-story displacement and overturning moment of the structure under velocity pulse-like ground motions are significantly higher than those under non-velocity pulse-like ground motions.The vertical irregularity has a significant impact on the structural elastic-plastic seismic demand.The inter-story displacement angle increases with a decreasing vertical irregularity ratio,while the inter-story shear force and overturning moment show a slightly decreasing trend.It is suggested that the coupling effects of velocity pulse-like motions and the vertical irregularity should be considered in the design of new gravity column core tube structures.