地震动持时效应对阻尼折减系数的影响  

EFFECTS OF GROUND MOTION DURATION ON DAMPING REDUCTION FACTOR

作　　者：周靖[1] 周飞[2,3] 

机构地区：[1]湘潭大学土木系,湖南湘潭411105 [2]华南理工大学土木系,广东广州510640 [3]广东省高教建筑规划设计院,广东广州510631

出　　处：《工程力学》2009年第2期78-84,共7页Engineering Mechanics

摘　　要：阻尼折减系数是建筑抗震设计中确定设计地震作用的重要参数之一。该文采用简谐正弦波和25条集集地震记录,基于单自由度体系不同阻尼比水平的位移反应谱研究了有效地震动持时对阻尼折减系数影响。分析结果表明:阻尼折减系数随有效地震动持时比和简谐激励循环数的增加而减小。基于分析结果的统计平均值,通过非线性多元回归分析给出了考虑地震动持时影响的阻尼折减系数谱。Damping reduction factor is one of the important parameters to determine the design earthquake force for building＇s structural seismic design. Employing the displacement response spectra of single-degree-of freedom systems with different levels of damping ratios, the present study investigates the effects of the effective ground motion duration on damping reduction factor. The ground motion durations are associated with 25 Chi-chi earthquake records and harmonic sine wave. The study shows that damping reduction factor decreases with the increasing of the effective duration of the ground motion and the number of cycles of harmonic excitation. A nonlinear multiple regression analysis based on the statistical mean value of the present study is employed, and a modified damping reduction factor considering the effects of ground motion duration is suggested.

关 键 词：抗震设计 地震动持时 阻尼折减系数 位移反应谱 有效持时 

分 类 号：P315.9[天文地球—地震学] TU352.1[天文地球—固体地球物理学]