建筑结构学报2018，Vol.39Issue(2)：44-53,10.DOI:10.14006/j.jzjgxb.2018.02.005
钢支撑-混凝土框架动力非弹性扭转机理与抗扭设计研究
Mechanism of dynamic inelastic torsion and anti-tosional design strategy of steel-braced concrete frames
摘要
Abstract
With shaking table tests of steel braced concrete frames,an issue of suddenly increasing torsion duo to steel brace buckling or other elements damage,i.e.inelastic torsion,is studied.Test results indicate that steel brace buckling or failure would be the main cause of the inelastic torsion in this kind of buildings.Based on the test results,the mechanism of the suddenly increasing inelastic torsion is studied,some FEM models of calculation examples with preseting occasional eccentricity are established,and nonlinear analysis are conducted.With the analytical models,the sudden increasing torsion issue is verified still existed while the number of elements in symmetric structure is increased but the brace number remains unchanged.It is cleared that even if it is a symmetrical structure,both routings of brace buckling or its re-straightening will induce the inelastic torsion and its sudden increase.Although there are inelastic torsion in pure concrete frames,but it perform a smaller torsional amplitude increment than steel braced one under same loading and eccentricity conditions,and not only tests but also analytical models reveal the similar phenomenon.With installed buckling-restrained braces (BRB)in concrete frames,it has been proved significantly effective to resist nonlinear torsion,superior to steel braced concrete frame or pure concrete frame.There are suggestions to structural engineers as follows:installing BRB is suggested to effectively minimize and control the inelastic torsion of concrete frames,it is recommended that a non-linear FEM analysis with preset occasional floor mass eccentricity to get inelastic torsion under strong earthquakes,and the maximum torsional response should be limited to a reasonable value in seismic design stage.关键词
钢支撑-混凝土框架/非弹性扭转/防屈曲支撑/振动台试验/抗扭设计Key words
steel-braced concrete frame/inelastic torsion/buckling-restrained brace/shaking table test/anti-tosional design分类
建筑与水利引用本文复制引用
高向宇,李建勤,刘超,李杨龙..钢支撑-混凝土框架动力非弹性扭转机理与抗扭设计研究[J].建筑结构学报,2018,39(2):44-53,10.基金项目
国家自然科学基金项目(51378038),北京市自然科学基金重点项目(8141001). （51378038）
