多层冷弯薄壁型钢结构房屋刚性楼盖判定及适用性研究

Research on determination and applicability of rigid floor of multi-storey cold-formed thin-walled steel structural building

为分析多层冷弯薄壁型钢结构房屋中组合楼盖的面内刚度,确定水平荷载在多层房屋结构分析中的传递分配关系,对6层足尺的冷弯薄壁型钢结构房屋进行了振动台试验,测取了模型的动力特性和地震响应,试验结果表明:试验模型具有良好的变形能力和抗震性能,在7度设防和罕遇地震作用下结构构件未发生塑性破坏;房屋模型中的组合楼盖可判定为刚性楼盖。采用ABAQUS有限元软件对房屋模型进行了地震响应模拟分析,验证了建模方法的正确性,并研究了不同烈度地震作用下抗侧墙体间距对组合楼盖传递分配水平地震剪力的影响规律,研究结果表明,组合楼盖传递水平地震剪力的能力随着输入地震波峰值加速度和抗剪墙体间距的增加而降低。提出了冷弯薄壁型钢-OSB板组合楼盖和冷弯薄壁型钢-混凝土组合楼盖在6度、7度及8度多遇地震作用时适用的抗侧墙体最大间距限值,可为完善轻钢结构相关规范提供参考。

In order to analyze the in-plane rigidity of composite floor in multi-storey cold-formed thin-walled steel structural buildings and determine the transfer and distribution relationship of horizontal load in structural analysis,a shaking table test was carried out on a six-storey full-scale cold-formed thin-walled steel structural building.The dynamic characteristics and seismic response of the model were obtained.The test results show that the test model has good deformation capacity and seismic performance.The structural components do not undergo plastic damage under the seismic action with fortification intensity and rare intensity of 7 degree.The composite floor in test model can be identified as rigid floor.Finite element software ABAQUS was used to simulate and analyze the seismic response of the test model,which verified the correctness of the modeling method.The influence law of the shear wall spacing on the transmission and distribution of horizontal seismic shear force of the composite floor under different seismic intensities was studied.The results show that the ability of composite floor to transfer horizontal seismic shear force decreases with the increase of peak acceleration of input seismic wave and shear wall spacing.The applicable maximum shear wall spacing limits of cold-formed thin-walled steel-OSB composite floor and cold-formed thin-walled steel-concrete composite floor under the frequent seismic actions of 6,7 and 8 degrees were proposed.Research results can provide reference for improving the relevant specifications of light steel structures.