（1 南京林业大学土木工程学院， 南京 210037； 2 东北大学后勤服务总公司， 沈阳 110004）

［摘要］针对竹结构受弯构件截面刚度低、承载力与跨越能力不足等应用局限，提出预应力FRP筋增强竹梁的方法，给出了其关键制造工艺。制作了4个预应力FRP筋增强竹梁和1个对比竹梁，研究参数包括FRP筋直径和预应力大小。结果表明，预应力FRP筋增强竹梁破坏始于梁底边缘竹材纤维受拉断裂，预应力的施加能够使竹材的抗压强度利用得更加充分，破坏时的延性特征更为明显，预应力FRP筋增强竹梁对应各个相关规范挠度限值时的荷载值都得到了较大提高，预应力的施加使得构件截面刚度得到了有效的提高，其提高幅度随着施加预应力的增大而增大。采用复合梁理论对预应力FRP筋增强竹梁试件的截面刚度进行预测，结果表明截面刚度预测结果与试验结果吻合很好。

［关键词］竹结构； 预应力； FRP筋； 力学性能

中图分类号：TU366-1文献标识码：A文章编号：1002-848X(2018)10-0108-06

Experimental study on mechanical properties of bamboo beam reinforced with prestressed FRP bars

Cheng Xunyu1, Wei Yang1, Xu Yang1, Li Guofen1， Wang Xuefeng2

(1 College of Civil Engineering, Nanjing Forestry University, Nanjing 210037, China;2 Northeast University Logistics Service Corporation, Shenyang 110004, China)

Abstract:Aiming at the application limitations of bamboo flexural members such as low stiffness, insufficient bearing capacity and insufficient span capacity, it was proposed to use prestressed FRP bars to strengthen bamboo beams and its key manufacturing process was given. Four bamboo beams strengthened with prestressed FRP bars and one control bamboo beam were manufactured. The parameters studied included the diameter of the FRP bars and the value of the prestress force. The results show that the failure of the bamboo beams strengthened with prestressed FRP bars occurs by the tensile rupturing of the bamboo fiber at beam bottom. The occurrence of the prestressed force can make the compressive strength of the bamboo to be more fully utilized and the ductility characteristics at failure become more obvious. The load values of the strengthened bamboo beam are greatly increased when they reach the deflection limits prescribed by relevant standards. The prestress force makes the sectional stiffness of the flexural members effectively increase, and the increase in amplitude increases with the increase of prestressing force. The composite beam theory was used to predict the sectional stiffness of the bamboo beams strengthened with prestressed FRP bars. The results show that the predicted sectional stiffnesses are in good agreement with the experimental results.

Keywords:bamboo structure; prestress; FRP bar; mechanical property

*国家自然科学基金项目（51208262，51778300），江苏省自然科学基金项目（BK20151520），江苏省“333”工程（BRA2016421）和“青蓝工程”项目（QL2017），江苏高校优势学科建设工程资助项目（PAPD），江苏省研究生科研与实践创新计划项目（KYCX17-0830）。

通讯作者：魏洋，博士，教授，博士生导师，Email:wy78@njfu.edu.cn。