摘要
为了研究多层屈曲约束支撑钢框架(Buckling Restrained Braced Frame,简称BRBF)在屈曲约束支撑(Buckling Restrained Brace,简称BRB)分担率β值较高时,层剪力的优化分布,对β值约为0.9的框架振动模型(MF)和质点系振动模型(MS-0、MS-1和MS-2)进行弹塑性时程分析,研究其层剪力、层间位移角、最大倾覆弯矩及支撑固定柱的地震响应。研究结果如下:β值较高时,MF层响应值,中低楼层与质点系振动模型吻合较好,上部楼层接近质点系振动模型MS-1和MS-2。采用静力推倒法进行抗震设计时,修正底部剪力法的F1i和F2i模型分析结果与实际情况更吻合。用底部剪力法设计高β值的BRBF,存在结构柱的地震静力等效值被低估的可能性,有一定程度的安全隐患。在强震作用下,第2振型卓越,上部楼层层反应值较大。
To optimize the distribution of inter-story shear force under high BRB sharing value β in multi-story Bucking Restrained Braced Frame（BRBF） structures, the elastic-plastic time-history analysis is conducted on vibration model （MF） and model of particle system （MS-0, MS-1 and MS-2）, for evaluating inter-story shear force,inter-story drift, the maximum overturning moment and the response of bracing fixed column under earthquake. The results show that structural story response with high fl value fits well with that of the particle system vibration model at the lower part of the building,while the upper floor matches vibration model MS-1 and MS-2. In the push-over analysis for seismic design, the modified base-shear, Fli and F2i, are consistent with the actual situation. Also, for the design with high β values,the base-shear analysis methods may underestimate the static equivalent value of structural column, and this leads to structural safety issues. Under strong earthquakes, the second vibration mode is predominant, and the earthquake response is more significant in the upper floors.
出处
《建筑钢结构进展》
CSCD
北大核心
2015年第3期39-46,共8页
Progress in Steel Building Structures
基金
国家自然科学基金(41272358
51068004)
广西自然科学回国基金(2011GXNSFC018004)
广西高等学校特色专业及课程一体化建设项目(GXTSZY232)
关键词
设计层剪力分布
框架振动模型
质点系振动模型
层反应值
designed inter-story shear distribution
structural frame vibration model
vibration model of particle system
story response
