面向时变阻尼比-位移双目标的防屈曲支撑减震体系设计方法  

Time-varying damping ratio and displacement double objective design method of BRB damping structure

作　　者：吴山 何浩祥[1] 陈易飞 WU Shan;HE Hao-xiang;CHEN Yi-fei(Beijing Key Lab of Earthquake Engineering and Structural Retrofit,Beijing University of Technology,Beijing 100124,China)

机构地区：[1]北京工业大学工程抗震与结构诊治北京市重点实验室,北京100124

出　　处：《振动工程学报》2022年第3期663-673,共11页Journal of Vibration Engineering

基　　金：国家自然科学基金资助项目(51878017);国家重点研发计划(2017YFC1500604)。

摘　　要：附加阻尼比是消能减震体系设计中的重要性能参数,传统方法采用阻尼器滞回耗能和减震体系总应变能的比值作为量化结果,并通常采用双线性模型计算防屈曲支撑滞回耗能,计算精度较低。采用积分方法推导能够精确反映阻尼器滞回性能的Bouc-Wen模型的滞回能量显式化解析表达式,并提出分别基于应变能法和模态阻尼耗能法的时变附加阻尼比计算方法。为了准确控制减震体系的阻尼比,将减震体系层间位移角不超限和附加有效阻尼比作为控制目标,阻尼器的布置方案和阻尼力的大小作为设计变量,提出面向阻尼比-位移双目标的减震体系设计方法和流程。对一钢混框架减震体系进行迭代设计和分析,确定计算时变滞回能量的合理时段长度,并对不同的时变阻尼比计算方法进行比较。结果表明:基于应变能法的附加阻尼比偏大,不利于结构安全,建议采用模态阻尼耗能法的平均值表征附加有效阻尼比。Additional damping ratio(ADR)is an important performance parameter in the design of energy dissipation system.The ratio of the hysteretic energy dissipation of the damper to the total strain energy of the damping system is used as the quantitative ADR in the traditional method,and the bi-linear model is usually used to calculate the hysteretic energy dissipation of the bucklingrestrained brace(BRB).The accuracy of the above calculation methods is low.The explicit analytical expression of the hysteretic energy of Bouc-Wen model which can accurately characterize the hysteretic performance of the damper is derived by integral method,and time-varying ADR calculation methods based on the strain energy method and the modal damping energy dissipation method are proposed.In order to accurately achieve the damping ratio of the damping system,the inter-story displacement angle and damping ratio of the damping system are taken as the control objectives,and the layout scheme and damping force of the damper are taken as the design variables.The design method of damping ratio-displacement double objective is proposed.The iterative design and analysis of a RC frame damping system are carried out.The reasonable length of time interval for calculating time-varying hysteretic energy is determined,and different calculation methods of time-varying ADR are compared.The results show that the ADR based on the strain energy method is larger,which is not conducive to the structural safety.It is suggested to use the average value of modal damping energy dissipation method to characterize ADR.The double objective design method is reasonable,and the performance requirements are more detailed and accurate.

关 键 词：耗能减震 附加有效阻尼比 应变能法 模态阻尼耗能法 防屈曲支撑 

分 类 号：TU318[建筑科学—结构工程] TU352.1