双向水平地震作用下六层冷弯薄壁型钢-钢板剪力墙结构振动台试验研究

Study on shaking table tests of a six story full-scale cold-formed steel-steel plate shear wall structure under bidirectional horizontal earthquake excitations

为反映多层冷弯薄壁型钢-钢板剪力墙结构在水平地震作用下的受力性能,分别对施工阶段及正常使用阶段的六层房屋足尺模型开展双向地震动输入的振动台试验,试验中考虑了8度多遇至8度罕遇等7个地震烈度(0.07g~0.40g)。通过对比其破坏特征、动力特性、位移和应变响应,研究非结构构件对整体结构抗震性能的影响并进行楼盖刚性判定和房屋扭转响应分析。研究结果表明:在水平地震作用下模型的主要破坏特征为轻质墙面板螺钉连接破坏;蒙皮普通墙体与钢板剪力墙共同抵抗水平剪力,提高了结构的抗震性能;随输入加速度峰值增大,结构的自振频率降低,位移响应及立柱应变提高;冷弯薄壁型钢梁-压型钢板覆水泥纤维板组合楼盖可判定为刚性楼盖;结构扭转响应较小;在8度多遇及8度罕遇地震作用下,结构最大层间位移角分别为1/505、1/100,满足规范规定的弹性及弹塑性层间位移角限值1/250及1/50的限值要求,多层冷弯薄壁型钢-钢板剪力墙结构具有良好的变形能力和抗震性能。

In order to describe the mechanical performance of multi-story cold-formed steel-steel plate shear wall structures(CFS-SPSWS)under horizontal earthquake excitation,full-scale shaking table tests with bidirectional seismic input were performed on a six-story building model under construction stage and normal use stage.Seven seismic intensity levels ranging from 8 degree frequent to 8 degree rare earthquakes(0.07g-0.40g)were considered in the tests.Failure characteristics,dynamic characteristics,displacement response and strain response were compared,the influence of nonstructural components on the global seismic performance were explored,and the stiffness of the floors and the torsional response of the building were analyzed.The test results show that the failure characteristics of the model under horizontal earthquake is screw connection failure of lightweight wall panels;sheathed primary walls and steel plate shear walls resist horizontal shear force together,which improves the seismic performance of the overall structure;with the increase of input excitation acceleration peak value,the natural frequency decreases,and the displacement response and strain response of studs increase;the CFS joist-steel deck sheathed cement fiber board composite floor can be determined as a rigid floor;the torsional response of the structure is small;the maximum inter story displacement angles under 8 degree frequent and 8 degree rare earthquakes were 1/505 and 1/100 respectively,which meet the limit requirements of 1/250 and 1/50 of elastic and elastic-plastic interlayer displacement angle specified in the specification,and the multi-story CFS-SPSWS has good deformation capacity and seismic performance.