掉层RC框架结构的横坡向扭转规律分析  

Analysis of torsional effect perpendicular to the slope direction of RC frame structure supported by foundations with different elevations

作　　者：沈程[1] 李英民[2] 岳翎 姜宝龙[2] 唐洋洋 Shen Cheng;Li Ying-min;Yue Ling;Jiang Bao-long;Tang Yang-yang(Institute of Civil Engineering,Changzhou Vocational Institute of Engineering,Changzhou 213164,China;School of Civil Engineering,Chongqing University,Chongqing 400045,China)

机构地区：[1]常州工程职业技术学院建筑工程学院,江苏常州213164 [2]重庆大学土木工程学院,重庆400045

出　　处：《工程抗震与加固改造》2023年第5期56-63,共8页Earthquake Resistant Engineering and Retrofitting

基　　金：国家自然科学基金(51638002);江苏省高校自然科学基金项目(19KJD410001)。

摘　　要：对掉层RC框架结构的弹性扭转特征进行分析,并基于掉层RC框架结构的扭转特征提出将相对偏心距作为反映其扭转程度的参量,根据“等代柱”思想提出了简化的计算方法,分析了结构在横坡向单向地震作用下的弹性及弹塑性扭转反应规律,以及相对偏心距与结构扭转程度的对应关系。结果表明:横坡向地震作用时,掉层RC框架结构在掉层侧和上接地侧变形差异较大,结构扭转反应明显;掉层部分跨数的改变对掉层部分和上接地层的扭转反应影响程度更大些;弹塑性阶段,结构上接地侧柱破坏相对掉层侧严重,且相对偏心距>0.65时,上接地侧柱端破坏大于OP状态的比例显著增大;本文提出的简化方法得到的相对偏心距在弹性和弹塑性阶段均能较好地反映结构的扭转程度。In this paper,the elastic torsional characteristics of RC frame structure supported by foundations with different elevations are analyzed,and eccentricity ratio is proposed as the parameter to measure the degree of torsional effect based on its torsional characteristics.A simplified calculation method of eccentricity ratio is presented according to the idea of the equivalent column.The elastic and elastic-plastic torsional responses of the structures under unidirectional seismic action perpendicular to the slope direction are analyzed,and the relationship of eccentricity ratio and structural torsional effect is obtained.The results indicate that the deformation of RC frame structure supported by foundations with different elevations is obviously different between the side of lower embedding end and the side of upper embedding end under seismic action perpendicular to the slope direction,and the torsional effect is significant.The torsional effect of floors under upper embedding ends and upper embedding floor changes more noticeable when the number of span of floors under upper embedding end changes.In the elastic-plastic stage,the column damage at the side of upper embedding end is more serious than that at the side of lower embedding end,and the proportion of damage state of the former greater than OP increases significantly when the eccentricity ratio is greater than O.65.The eccentricity ratio obtained by the simplified method can reflect the extent of torsional effect of the structure well in both elastic and elastic-plastic stages.

关 键 词：掉层RC框架结构 扭转反应 相对偏心距 横坡向 

分 类 号：TU317.1[建筑科学—结构工程]