海域地震动竖向加速度反应谱阻尼修正系数  

DAMPING MODIFICATION FACTOR FOR VERTICAL ACCELERATION SPECTRUM FROM OFFSHORE GROUND MOTIONS

作　　者：刘名吉 胡进军[1,2] 石昊 谭景阳 LIU Ming-ji;HU Jin-jun;SHI Hao;TAN Jing-yang(Institute of Engineering Mechanics,China Earthquake Administration,Harbin 150080,China;Key Laboratory of Earthquake Engineering and Engineering Vibration,China Earthquake Administration,Harbin 150080,China)

机构地区：[1]中国地震局工程力学研究所,哈尔滨150080 [2]中国地震局地震工程与工程振动重点实验室,哈尔滨150080

出　　处：《工程力学》2023年第4期162-171,共10页Engineering Mechanics

基　　金：国家自然科学基金项目(52078470,U1939210,51578516)。

摘　　要：该文提出了一个用于调整5%阻尼比海域地震动竖向加速度反应谱的阻尼修正系数(Damping modification factor,DMF)模型。基于S-net台网的5680条海底竖向地震动记录,利用DMF比值和Z检验分析了地震类型对DMF的影响,提出了考虑阻尼比和谱周期的DMF模型,与陆域DMF模型进行了对比,并获取了不同阻尼比下的竖向加速度反应谱,最后对残差及标准差进行分析。研究表明:地震类型对DMF的影响可以忽略;可用三次多项式模拟阻尼比对DMF的影响;由于海域地震动特性导致海陆DMF模型之间差异显著;阻尼比能够影响5%阻尼比反应谱1倍标准差的谱值;残差分析表明可引入矩震级、断层深度和震源距改善DMF模型的拟合度。该文提出的海域地震动加速度谱竖向DMF模型,为海域工程多阻尼抗震设计谱的确定提供了参考。A damping modification factor(DMF)model for adjusting the vertical acceleration response spectrum of offshore ground motions with a damping ratio of 5%is proposed.Based on 5680 offshore vertical ground motion records from S-net network,the influence of earthquake types on DMF is analyzed by using DMF ratios and Z tests.A DMF model is proposed through considering damping ratios and spectral periods,and compared with the onshore DMF model,by which the vertical response spectra are obtained for other damping ratios.Finally,the residuals and standard deviations of the model are analyzed.The results show that the influence of earthquake types on DMF can be ignored.The influence of damping ratio on DMF can be simulated by a cubic polynomial.Due to the characteristics of offshore ground motions,there are significant differences between offshore and onshore DMF models.The damping ratios can affect the spectral value of one standard deviation of the response spectrum of 5%damping ratio.Residual analysis shows that moment magnitude,fault depth and source distance can be introduced to improve the fitting of DMF model.The DMF model for vertical response spectrum proposed provides a reference for the determination of multi-damping ratios seismic design spectra of offshore engineering.

关 键 词：海域地震动 阻尼修正系数 残差分析 加速度反应谱 竖向分量 

分 类 号：TU202[建筑科学—建筑设计及理论] P315.9[天文地球—地震学]