铝-木组合梁受弯性能研究

Research on Flexural Behavior of Aluminum-wood Composite Beam

提出一种以T型带肋定向结构刨花板(oriented strand board,OSB)为骨架,梁腹板下表面与铝板通过螺钉连接组成的铝-OSB板T形截面带肋组合梁(简称为铝-OSB板组合梁)。以组合梁的腹板高度和铝板厚度为参数,设计了4根铝-OSB板T形截面带肋组合梁试件,对各个试件进行抗弯性能的试验,观察在各级荷载作用下试件的破坏过程和破坏形态、OSB板和铝板的应变变化以及组合梁跨中挠度的变化规律。建立ABAQUS有限元模型,对比有限元模拟与试验的结果,并且分析不同螺钉间距对组合梁受弯性能的影响。试验结果表明:在达到极限承载力时,各组合梁的铝板均达到屈服应变;组合梁中OSB板和铝板能够同时参与工作,整体工作性能好,组合效应显著;提高组合梁的腹板高度和铝板厚度可以不同程度地提高组合梁的受弯承载力,且腹板高度对组合梁的受弯性能影响远大于铝板厚度对其的影响;有限元分析结果与试验结果吻合良好;基于有限元模拟的分析表明,随着螺钉间距的减小,组合梁的承载力会有所提高。

A new type of aluminum sheet-orvented strand board(OSB)composite T-beam with lateral OSB ribs(referred as aluminum-OSB composite beam)was presented.The T-shaped OSB board was taken as the backbone,and a lower surface of the web and an aluminum sheet were connected by screws.Based on the height of the web and the thickness of the aluminum sheet,four specimens of the aluminum sheet-OSB composite T-beam with lateral OSB ribs were designed.The three-point loading test was carried out to investigate the flexural behavior of the composite beams and the failure modes.The strain in the OSB board and aluminum sheet and the deflection of composite beams were measured.The ABAQUS finite element model was established,and the results of finite element simulation and experiment were compared.The influence of different screw spacing on the flexural behavior of the composite beam was also analyzed.The test results show that the aluminum sheet of each composite beam reach the yield strain when the ultimate bearing capacity is reached.The OSB board and the aluminum sheet in the composite beam can participate in the work at the same time,and the overall working performance is great and the combined effect is significant.The flexural capacity of composite beams can be improved at different degree by increasing the height of the web and the thickness of the aluminum sheet,and the influence of the height of the web on the flexural performance of composite beams is much greater than that of the thickness of the aluminum sheet.The results of finite element model has a good agreement with experimental results.The analysis based on finite element simulation shows that the flexural capacity of the composite beam will increase as the screw spacing decreases.