【作者】 吴传伟；

【导师】 高轩能；

【作者基本信息】 华侨大学 ， 结构工程， 2009， 硕士

【摘要】 由冷弯薄壁型钢桁架和OSB板组成的组合楼盖体系是轻钢结构住宅中一种富有特色的新型结构体系,对推动冷弯薄壁型钢结构住宅在我国的发展,具有十分重要的意义。为科学认识其整体承载性能并为其在我国的推广应用提供依据,论文对冷弯薄壁型钢组合楼盖的整体承载能力进行了理论及试验研究。在试验研究方面,首先,对钢材和OSB板进行了材性试验,得到了材料的弹性模量和强度。其次,对单榀钢桁架,单榀组合桁架,三榀组合楼盖体系三组共9根试件进行了试验研究,试验取得了其极限荷载、变形曲线及破坏模式。最后,将试验与理论分析结果相对比,从而验证了理论分析模型的合理性、准确性和可靠性。组合楼盖体系在理论分析时,可将其看作是一种组合桁架体系,OSB板视为桁架上弦的一部分,通过连接件的作用与钢桁架上弦一起,成为组合桁架刚度强度都较大的上弦,再与腹杆、下弦共同形成实际的组合桁架。本文按弹性理论及塑性理论分别进行了分析,得到其承载力计算公式。在考虑材料非线性和几何非线性的基础上,建立了冷弯薄壁型钢组合楼盖整体承载力ANSYS计算模型,并在试验验证其有限元分析模型的合理性、准确性和可靠性的基础上对可能影响冷弯薄壁型钢组合楼盖整体承载力的各种因素进行了分析。通过理论分析及试验研究,得到以下主要结论:(1)冷弯薄壁型钢组合楼盖具有很大的刚度,在外部荷载作用下变形很小;(2)由于OSB板的连接作用,冷弯薄壁型钢组合楼盖不会发生平面外失稳现象;(3)当冷弯薄壁型钢组合楼盖的榀数达到三榀以上时,其力学性能的差别很小,可以用三榀组合楼盖作为整体组合楼盖的计算单元;(4)组合楼盖主要靠钢桁架来受力,钢桁架间距是影响组合楼盖受力性能的重要因素;(5)OSB板的厚度对组合楼盖受力性能影响较小;(6)组合楼盖的跨度是影响其受力性能的重要因素;(7)密排的自攻螺钉可以有效的防止钢梁与OSB板间的相对滑移。更多还原

【Abstract】 Composite floor system is a new type of residential building system in light-gauge steel residence which is composed of cold-formed thin-wall steel truss and OSB board. It is very important to promote the development of cold-formed thin-wall steel residence in China. In order to realize the integral bearing behavior of cold-formed thin-wall steel composite floor and provide credibility basis of promotion in our country, theoretical and experimental researches are carried out.Firstly, material tests of both steel and OSB board are taken to get the elastic modulus and ultimate strength. Secondly, nine specimens including single steel truss, single composite truss, three composite floor system are tested to get the ultimate load, deformation curve and failure mode. Lastly, it is showed that the theoretical analysis model is rational, exact and reliable by comparing the results of experiment and the theoretical analysis.Composite floor can be simplified to composite trusses in the theoretical analysis. The composite truss is composed of top chord of composite truss, bottom chord of composite truss and web member. The top chord of composite truss is composed of top chord of truss and OSB board that’s attached to top chord of truss with self-drilling screws can be considered as a part of top chord of truss. The bearing capacity formula of composite trusses was presented by elastic and plastic theory analysis. Considering the nonlinearity of the material and geometry, nonlinear finite element model was set up for calculating the integral bearing capacity of cold-formed thin-wall steel composite floor, and then, based on the rational, exact and reliable theoretical analysis model validated by experimental results, some factors which may be affect integral bearing capacity of cold-formed thin-wall steel Composite floor have been taken account of in parameter analysis.Though theoretical and experimental researches, the paper gives some conclusions as follows: (1) cold-formed thin-wall steel composite floor shows a large stiffness and small deformation under external loads; (2)out -of-plane instability phenomenon could not happen in cold-formed thin-wall steel composite floor because of the connective function of OSB board; (3) three Composite floor system can be considered as a calculating unit of integral composite floor because the difference of mechanical properties is very small when there are more than three composite floors; (4) The distance of steel truss is a important factor which affect the bearing capacity of composite floor because steel truss is the main bearing structure;(5) The thickness of OSB board has little influence on the mechanical properties of composite floor;(6)The span of composite floor has great influence on the mechanical properties of composite floor; (7) The relative slip between steel truss and OSB board can be prevented effectively by close-packed self-drilling screws.更多还原