装配式刚边框-冷弯薄壁型钢骨架组合墙体受力性能研究

冷弯薄壁型钢组合墙体主要由冷弯薄壁型钢骨架和外敷面板组成,结构轻巧,绿色环保,多用于中低层建筑,一般在施工现场拼装完成。为提升墙体的施工速度和安装效率,在墙体四周增设焊接刚性边框,提出一种新型装配式刚边框-冷弯薄壁型钢骨架组合墙体,该墙体在工厂预制完成,现场采用螺栓与周围构件连接。建立有限元模型分析面板类型、斜撑、螺钉间距、刚边框和洞口对该新型墙体受力性能的影响,提出了承载力设计方法。研究结果表明:增设斜撑能提升墙体骨架的抗侧刚度以及石膏板覆面墙体的受剪性能,对受压承载力以及OSB板覆面墙体的抗剪承载力影响较小;墙体宜采用较密的螺钉间距(面板四边100 mm,内部300mm),便于充分发挥刚性边框的作用,且刚性边框无须过厚;带洞口墙体通常在洞口角部发生破坏,其受剪承载力随着洞口尺寸的增大而大幅下降,洞口位置对受剪性能影响较小。

Research on the Mechanical Property of Prefabricated Cold-Formed Thin-Walled Steel Composite Wall with Rigid Frame

Cold-formed thin-walled steel composite wall is fabricated with cold-formed steel framework and sheathed plate.This wall has the advantages of light and green,and is suitable for middle and low-rise buildings.It is often assembled at the construction site.In order to improve the construction speed and assembly efficiency,a new prefabricated cold-formed thin-walled steel composite wall with rigid frame was proposed,by adding rigid frame at external edge.The new wall can be fabricated at factory and built using bolts on site.A finite element method is established and used to analyze the influence of board type,diagonal brace,screw spacing,rigid frame and opening on the load capacity of wall,and the design methods are proposed.The results show that diagonal braces can improve the lateral stiffness and the shear capacity of new wall sheathed with gypsum,but have little influence on the axial bearing capacity and the shear capacity of the wall sheathed with oriented strand board.It is better to adopt a short screw spacing(100 mm at board edge and 300 mm inside the board)to allow the rigid frames to reach their full capacities,and the rigid frame need not to be too thick.The new wall usually fails at the corner of the opening,the shear capacity decreases greatly with the increase of the size of opening,but the position of the opening has little effect on shear performance.