某竖向框排架结构中排架部分层间位移角限值的研究

A STUDY OF THE LIMIT VALUE FOR STORY DRIFT ANGEL IN A VERTICAL FRAMED BENT STRUCTURE

针对GB 50011—2010《建筑抗震设计规范》中排架柱在罕遇地震作用下层间位移角限值取值问题,对一个实际的火电厂汽机房竖向框排架结构进行分析。首先针对结构中的单根排架柱进行不同初始转角和不同轴压比的非线性分析,结果表明:1/40的层间位移角限值能较安全和经济地评价算例中排架柱的抗震性能;然后对整体结构进行了不同场地类别罕遇地震作用下的动力弹塑性分析,从层间位移角的宏观指标和基于材料塑性变形定义的构件损伤指标对该结构算例中的排架部分进行抗震性能评价,进一步验证了1/40的层间位移角限值对结构排架部分的抗震性能评价能更好地与基于材料塑性变形定义的构件损伤指标的评价结果相吻合。

To study the story drift angle limitation of bent frame column under strong seismic action,the paper analyzed a vertical framed bent structure of a power plant steam engine room. Firstly,nonlinear finite-element analysis of a framed bent column with different initial angles and axial compressions ratio was made. The analysis results indicated that the story drift angle limitation of 1 /40 could give satisfied evaluation of aseismic behavior of the framed bent column safely and economically. And then,the dynamic elastic-plastic analysis under strong seismic action of different characteristic sites for the whole structure was conducted. The aseismic behavior of framed bent column was evaluated using the macroscopic evaluation indexes of story drift angle and the microcosmic evaluation index of material strain. The evaluation results of the story drift angle limitation of 1 /40 agreed well with those of the index of material strain.