冷弯薄壁型钢-OSB双向板组合楼盖试验研究

Experimental Research of Cold-formed Thin-walled Steel OSB Two-way Composite Floor

为了研究冷弯薄壁型钢与定向结构刨花板(oriented strand board,OSB)板连接而成的双向板组合楼盖的抗弯承载力性能,设计制作一个3.7 m×3.7 m的足尺组合楼盖试件,在四边简支条件下对其进行单调静力堆载试验,并建立了冷弯薄壁型钢-OSB板组合楼盖的非线性有限元分析模型。在此基础上,通过改变OSB板梁腹板高度、冷弯薄壁型钢板厚度与螺钉间距来分析各参数对组合楼盖受力性能的影响。试验结果表明:OSB板与冷弯薄壁型钢能够很好地协同工作,变形符合平截面假定。试件x与y两个方向上的组合承重梁荷载-挠度(P-Δ)曲线变化情况基本一致;随着梁腹板高度、钢板厚度的增加,组合楼盖的抗弯承载力明显增加;梁底冷弯薄壁型钢与OSB腹板的端部构造可以有效减小钢木接触截面的滑移变形。可见该组合楼盖双向受力性能良好,增加梁腹板高度,增大钢板厚度与适当减小螺钉间距均能提高楼盖的承载能力。

In order to study the bending resistance performance of the cold-formed thin-walled steel-oriented strand board(OSB)two-way slab composite floor.A full-scale composite floor test piece was designed and manufactured,and a monotonic static stacking test was performed on it under the condition of simply supported on four sides.The nonlinear finite element analysis model of the cold-formed thin-walled steel-OSB slab composite floor was established.On this basis,by changing the height of the OSB beam web,the thickness of the cold-formed thin-walled steel plate and the screw spacing,the influence of each parameter on the mechanical performance of the composite floor was analyzed.The experimental results show that OSB plate and cold-formed thin-walled steel can work well together and coordinate deformation.The load-deflection(P-Δ)curve of the composite load-bearing beam in the x and y directions of the specimen is basically the same.As the height of the beam web and the thickness of the steel plate increase,the flexural bearing capacity of the composite floor is significantly increased.The end structure of cold-formed thin-walled steel at the bottom of the beam and the OSB web can effectively reduce the slip deformation of the steel-timber contact section.It is concluded that the combined floor has good bidirectional force performance.Increasing the height of the beam web,increasing the thickness of the steel plate and appropriately reducing the screw spacing can improve the bearing capacity of the floor.