碳纤维布与钢板复合加固混凝土结构是一种新的加固形式,在其运用到实际加固工程时,关键是要保证碳纤维布与钢板之间的有效黏结.通过11组碳纤维布与钢板黏结剪切试验,分析了碳纤维布与钢板发生黏结剪切破坏的过程、破坏机理,并对碳纤维布的黏结宽度、碳纤维布的层数和黏结长度等对黏结剪切性能的影响进行了研究.研究结果表明,碳纤维布与钢板的有效黏结长度随着碳纤维布层数增加而增大,而与碳纤维布的宽度及粘贴长度无关;碳纤维布与钢板的极限黏结力随碳纤维布宽度增加而线性增大,且当黏结长度超过有效黏结长度后,极限黏结力不再随黏结长度增大而增加,但黏结破坏的延性得到改善.在试验研究的基础上提出了极限黏结力和有效黏结长度的计算公式,其计算结果和试验结果吻合较好,可为复合加固在工程上的应用提供参考.
Combination strengthening RC structures with carbon fiber reinforced polymer and steel plate is a new rehabilitation method, in which the effective bond between steel plate and CFRP is critical. An experimental study was conducted on the shear behaviors of 11 groups of specimens. The stress distribution characteristics, failure process and mechanism were investigated. The influence of width, thickness and adhesive length of CFRP on the adhesive shear properties was analyzed. The results indicate that the effective adhesive length increases with the number of CFRP layers. The width and the adhesive length have no effect on the effective adhesive length. The ultimate bond capacity increases linearly with the width of CFRP, until the adhesive length surpasses the effective adhesive length. Moreover, the ductility can be improved with increasing adhesive length. Based on the experimental study, calculation formulas for ultimate bond capacity and the effective adhesive length are established. The theoretical calculation resuits are consistent with the experimental ones.