摘要
防屈曲支撑在轴向荷载作用下均具有稳定的滞回、良好的耗能能力和低周疲劳性能,在实际工程中的应用越来越广泛。混凝土框架结构作为主要的结构体系之一,有相当一部分由于建造时未考虑抗震或抗震设防水准过低、使用功能改变或结构耐久性退化等原因,不能满足现有抗震规范要求,亟需进行抗震加固以提高抗震性能,避免结构在地震作用下发生倒塌,保证结构的安全性。利用防屈曲支撑加固既有混凝土框架结构,可以很大程度提高结构的抗侧刚度和耗能能力,改善结构的抗震性能。本文利用防屈曲支撑框架结构体系的简化抗侧刚度模型,采用附加刚度法来确定抗震性能不足的混凝土结构所需的防屈曲支撑抗侧刚度,给出了基于附加刚度的防屈曲支撑加固混凝土框架结构抗震设计流程。结合一个5层的宿舍楼进行了实例分析,通过非线性分析对该设计方法进行数值验证,结果表明,采用附加刚度法可快速确定防屈曲支撑的抗侧刚度需求和支撑设计,在设防地震和罕遇地震作用下具有明显的减震效果。
The buckling-restrained brace has stable hysteresis behavior,excellent energy dissipation capacity and fatigue behavior under axial load,and it has been widely applied in practice. As the most universal structure system,most existing RC frames in China don’t have adequate seismic performance due to the low level of seismic fortification,the change of use function and deterioration in ductility.Therefore,it is urgent to improve the seismic performance of these deficient RC frames to avoid the collapse and ensure the safety of the buildings. The favorable mechanical characteristics of buckling-restrained brace could offset the deficiency of RC frames and it could largely enhance the lateral stiffness and energy dissipation capacity of RC frame. In this paper,the stiffness of buckling-restrained braces needed for the enhancement in lateral stiffness are determined based on the method of additional stiffness,and the design process for retrofit of RC frame is proposed. The feasibility of design method is verified with a case study,and the result of nonlinear analysis demonstrates that design of buckling-restrained braces could be easily performed with the proposed method and the retrofitted structure exhibits good seismic behavior.
作者
赖秋兰
刘如月
lai Qiu-lan;Liu Ru-yue(School of Civil Engineering,Fujian University of Technology,Fuhou 350118,China;Fujian-Taiwan Cooperative Institute of Civil Engineering Technology in Universities of Fujian Province,Fuzhou 350118,China)
出处
《工程抗震与加固改造》
北大核心
2021年第3期116-125,共10页
Earthquake Resistant Engineering and Retrofitting
基金
福建省自然科学基金青年项目(2020J05185)
福建工程学院校科研发展基金项目(GY-Z18165)。
关键词
防屈曲支撑
混凝土框架
基于附加刚度抗震设计
抗震加固
非线性分析
buckling-restrained braces
RC frame
seismic design method with additive stiffness
seismic retrofit
nonlinear analysis
