多层石膏墙体钢网格式框架结构影响系数研究

Study on structural influencing coefficient of multistory steel grid frame with gypsum-wall

GB 50011—2010《建筑抗震设计规范》并未给出多层石膏墙体钢网格式框架结构的结构影响系数,因此其抗震设计荷载取值还不明确。基于此,依据GB 50011—2010规范设计了6个典型的多层钢网格式框架结构模型,通过推覆分析得出结构的能力谱曲线,基于改进能力谱法得出罕遇地震和抗震设防烈度地震作用下的需求谱曲线。将结构的能力谱曲线和延性需求谱曲线族置于统一坐标系中,确定结构的目标位移以及性能关键点坐标。进一步考虑层数及标准层布置对结构延性和超强系数的影响,评估结构的抗震性能并给出结构影响系数取值。研究表明:多层钢网格式框架结构在抗震设防烈度地震和罕遇地震作用下的变形均满足抗震规范要求;其结构影响系数取3.0,位移放大系数取4.0;该结构可采用现行抗震规范进行设计,但设计结果偏于保守。

Since the influencing coefficient of muhistory steel gird frame with gypsum wall has not been given in current Chinese seismic code, the determination method of the design seismic force was not clear. Six muhistory steel gird frame models were designed according to Chinese seismic design code. The global capacity spectrums of each model were got by pushover analysis, and the demand spectrums under rare and fortification earthquake were obtained by the improved capacity spectrum method. Mter drawing all the spectrum curves of each model in the same coordinate system, the target displacement and the performance key points were determined. Involving the effects of the building height and span of typical floor on structural ductility and over-strength capacity, the seismic performance of this new structure was studied and the structural influencing coefficient values were determined. It is found that the structural deformation under fortification and rare earthquake meets the requirements of codes. Structural influencing coefficient value is 3.0 and displacement magnification factor under rare earthquake is 4. 0. The current seismic codes are suitable for this structure, but the design results are conservative.