以竹集成材为翼缘、欧松板为腹板设计竹木组合工字梁,对10根不同结构的工字形截面竹木组合梁进行了4点弯曲静载试验.研究剪跨比及加劲肋等参数对组合梁破坏形态、强度和延性等影响.结果表明:腹板和翼缘具有很好的协同效果,组合梁的破坏始于侧向失稳,主要破坏形态表现为翼缘内欧松板层裂及腹板被剪坏.组合梁的极限承载力随着剪跨比的增大呈下降趋势;竹加劲肋能显著提高工字梁的极限承载力,提高幅度最大为15.7％,对极限位移最大增加幅度约为10.13％.

Holes are often made in the web of the OSB webbed bamboo I-joists for the passage of plumbing lines and ventilation systems. A comprehensive study was conducted in order to determine effect of the parameters, such as the size, shape and clear distance of the holes, on the behavior of the joists. A total of 92 OSB webbed bamboo joists were tested to failure to investigate the failure modes and failure mechanism of them. The results showed that holes in the web have considerable effect on the strength reductions of specimens. Holes sharply changes the stress state and reduces the strength evidently due to the high shear stresses appearing in the vicinity of the hole. With the increase of ratio of the hole size to web height, the peak load capacity and stiffness of the joists with holes decreased significantly. A web hole with sharp corners caused greater stress concentrations than the circular hole. Results from the tests on I shaped joists with two circular and two square web holes with a size of 50% web depth showed that the critical clear distance is about 2 times and 2.5 the web hole size respectively. (C) 2015 Elsevier Ltd. All rights reserved.