配筋重组竹受弯试件力学性能试验

Mechanical properties test of bamboo scrimber flexural specimens reinforced with bars

针对竹材弹性模量低、受弯试件截面刚度小、易发生受拉区竹纤维拉断破坏等不足,提出配筋竹结构的概念,给出了配筋竹结构的关键制造工艺,通过4个重组竹受弯试件的四点弯曲试验,研究了配筋竹试件的破坏形态及承载特性。研究参数包括筋材类型和筋材面积。研究结果表明,配筋试件的承载力及截面刚度显著提高,配置钢筋试件刚度提高效果优于FRP筋试件,由于配筋的增强作用,竹材的受压塑性能够充分发展,配筋试件表现出更加明显的塑性发展过程,其上、下边缘的极限压应变和极限拉应变均显著大于对比试件,截面应变分布符合平截面假定,内部筋材与外部竹材的应变对比表明内部筋材与竹材能够很好地共同工作。配筋竹结构是有效提高竹结构工作性能的一种新型结构。

For low elastic modulus of bamboo,insufficient cross-sectional stiffness and bamboo fiber feasible fracture in tension zone of bamboo flexural components,bamboo structure reinforced with bars and its manufacturing processes were presented.Four bamboo scrimber flexural specimens were studied by four-point bending test.The failure modes and load carrying characteristics of the reinforced bamboo components were investigated.The test parameters include the types and the cross-sectional area of reinforced bars.The results show that the load carrying capacity and section stiffness of the reinforced specimens increase significantly.Specimens reinforced with steel bars gain higher the sectional stiffness than those with fiber reinfored polymer(FRP)bars.Due to the effects of reinforced bars,the compress plastic behavior of bamboo can develop fully,and the reinforced specimens show more obvious plastic development process.Moreover,the top ultimate compressive strain and the bottom ultimate tensile strain of the reinforced specimens are significantly larger than the control specimen,and the cross-sectional strain distribution agrees with the plane section assumption.The strain comparison between internal bars and external bamboo in the same height shows that internal bars and bamboo can work well together.Bamboo structure reinforced with bars is a new structure to improve its work performance effectively.