胶合竹木工字梁受弯性能的试验研究

提出了一种以OSB为腹板骨架,OSB板外用环氧树脂胶黏剂和钉子连接竹集成材而成的胶合竹-木工字梁.以竹-木工字梁的腹板高度、剪跨比及加劲肋为参数,对24根竹-木工字梁的结构性能进行研究.分析了工字梁试验全程的破坏形态和破坏机理,探讨了其极限承载力、延性和抗弯刚度等,并研究影响其结构性能的因素.研究结果表明,竹-木工字梁整体工作性能优良,跨中截面应变沿梁高方向仍基本符合平截面假定,其极限承载力与截面高度、剪跨比和加劲肋有关.当剪跨比小于2.0时,组合梁出现了明显的剪压破坏特征,剪跨比越大,极限承载力呈显著下降趋势.加劲肋能显著提高工字梁的极限承载力,提高幅度为3.4%~38.0%,对极限位移的提高幅度约为1.7%~12.6%.加劲肋增强后的工字梁的初始抗弯刚度亦有大幅提高,提高幅度为10%~30%,腹板越高,增幅越大.

Bending Tests of OSB Webbed Bamboo I-Joist

A OSB webbed bamboo I-shaped joist connected and fixed by epoxy resin adhesive and nails was presented. The web height, shear span ratio and web stiffener were included as control parameters to see their effect on the flexural performance of 24 OSB webbed bamboo joists. The failure process, failure mechanism, deformation and carrying capacity were investigated and the shear capacities were also discussed. The results show that the composite joists show excellent combination performance, higher stiffness and strength. Also, the shear capacity of this joist has a close relationship with the shear span ratio and web height. When the shear span ration is less than or equal to 2.0, the failure modes were characterized by shear compression failure of the OSB web panels. The web stiffeners can markedly improve the ultimate load of the joists by 3.4%~38.0%, and is helpful to ultimate displacement and initial flexural stiffness by 1.7%~12.6% and 10%~30%, respectively. The web is higher and the growth is greater.