【摘要】 通过对多层RC平面框架结构在23条地震动记录2个不同强度水平下的非线性时程分析,得到RC框架的最大位移和残余位移等沿着楼层高度的大小和分布。统计分析残余层间位移角、最大层间位移角及两者比值这3个指标的均值、标准差和变异系数。为研究P-?效应的影响,对比是否考虑P-?效应两种工况下多层RC框架结构的分析结果。进一步,对多层RC框架的等效SDOF体系作同样的时程分析,对比了等效SDOF体系和多层RC框架结构的分析结果,研究高阶模态效应对RC框架的影响。对比分析表明,P-?效应和高阶模态效应对多层RC框架结构的残余位移响应的平均放大作用均大于其对最大位移响应的放大效应,残余位移响应的离散性也大于最大位移响应的离散性。另外,随着地震动强度水平的增加,结构地震响应的离散性明显增大。更多还原

【Abstract】 Nonlinear time-history analysis of RC planar frame was conducted under 2 intensity levels of 23 ground motion records. Amplitude and distribution of maximum and residual displacement response along the height were obtained and the mean values, standard deviations and variation coefficients of residual inter-story drift ratios, maximum inter-story drift ratios and their ratios were statistically analyzed. Analytical results of time-history analysis of multi-storey RC frame with and without accounting for P-△ effect were compared to investigate the influence of P-△ effect. Furthermore, the same time-history analysis was conducted on its equivalent SDOF system and the results were also compared to investigate the influence of higher mode effect. Comparison of the results show that amplification due to P-△ effect and higher mode effect on residual displacement response are averagely larger than amplification on maximum displacement response of multi-storey RC frame and dispersion of residual displacement response is also larger than dispersion of maximum displacement response. In addition, with increase of ground motion intensity level, the dispersion of seismic response becomes larger too.更多还原