【摘要】 在标准加速度反应谱基础上,研究并建立符合强震反应谱统计特征的谱阻尼折减系数是建立长周期、大阻尼比反应谱的一种实用方法。首先研究总结强震反应谱的统计特征,据此对我国建筑物、构筑物、核电厂、公路桥梁、工业企业电气设备等结构的抗震设计规范反应谱及谱阻尼折减系数的合理性进行定性研究,对已有改进抗震规范谱方案的合理性进行分析。结果表明:周期10 s内的相对位移反应谱值和相对速度反应谱值随阻尼比增大而减小,而绝对加速度反应谱值随阻尼比增大既可能增大也可能减小;我国各类结构抗震设计规范谱阻尼折减系数计算方案不甚合理;对规范谱及由有关学者提出的改进方案谱进行转换仅能得到适用范围有限的拟相对位移反应谱。更多还原

【Abstract】 The determination of the damping reduction factors of acceleration spectra that match the statistical characteristics of strong ground motions,based on the normalized acceleration spectra specified in the seismic codes,is a practical method to construct the design response spectra for long-period structures with damping ratios higher than 0.05.Statistical characteristics of earthquake response spectra were summarized first.Then qualitative investigations on the rationality of the seismic design spectra and spectral damping reduction factors in various Chinese seismic design codes including the codes for buildings,special structures,nuclear power plants,highway bridges and electrical facilities in industrial plants were performed.In addition,rationality of the improved seismic code spectra and spectral damping reduction factors was also discussed.The results show that values of both relative displacement spectra and relative velocity spectra will decrease along with the increase of the damping ratio.Values of absolute acceleration spectra will either decrease or increase along with the increase of the damping ratio.There are still no appropriate evaluation expressions for the damping reduction factors in the Chinese seismic design codes.The pseudo relative displacement spectra obtained from converting acceleration spectra in Chinese seismic design codes or modified acceleration spectra proposed by some researchers are only suitable for the seismic design of short-period structures with lower damping ratios.更多还原