预应力碳纤维板加固钢筋混凝土梁预应力损失试验研究  

Experimental study of prestress losses of RC beams strengthened with prestress FRP

作　　者：黄金林[1,2] 黄培彦[2] 郑小红[2] 

机构地区：[1]华南农业大学水利与土木工程学院,广东广州510642 [2]华南理工大学土木与交通学院,广东广州510640

出　　处：《建筑结构学报》2015年第1期85-91,共7页Journal of Building Structures

基　　金：广东省自然科学基金重点项目(9251064101000016);国家自然科学基金重点项目(11132004)

摘　　要：通过25根预应力碳纤维板加固钢筋混凝土梁试验研究,分析了预应力加固梁制作各工序的预应力损失。试验结果表明:当预应力水平分别为20%和30%时,预应力碳纤维板加固梁的平均预应力损失(相对于初始预应力)分别为14.38%和15.36%。对碳纤维板采取超张拉和二次超张拉技术,可以有效减小预应力损失。基于国内外混凝土结构设计规范的预应力损失计算方法,将预应力损失分为三部分:碳纤维板和锚具间的滑移引起的预应力损失、混凝土弹性压缩变形引起的预应力损失和碳纤维板应力松弛造成的预应力损失。在试验基础上,提出了三部分预应力损失的计算表达式,为预应力碳纤维板的加固设计提供参考。A total of 25 reinforced concrete( RC) beams strengthened with pre-tensioned carbon fiber reinforced polymer( CFRP) were conducted to investigate the prestress losses. Through monitoring the stains on CFRP,the total prestress losses were 14. 38% and 15. 36% relative to the original prestress respectively when the levels of prestressing were 20% and 30%. Over tensioning and twice-tensioning technology were carried out to reduce successfully the prestress loss in the study. Based on existing design specification for prestressed reinforced concrete structures,the prestress loss during the reinforced period contained three parts: prestress loss caused by the relative slip between CFRP and anchorage device; prestress loss caused by the elastic compression deformation of concrete; prestress loss caused by the stress relaxation of CFRP. The formula to calculate the prestress loss was proposed based on the experimental results,which would provide reference value for the design of prestressing FRP strengthening technology.

关 键 词：钢筋混凝土梁 碳纤维板 静载试验 预应力损失 

分 类 号：TU375.1[建筑科学—结构工程]