碳纤维增强塑料布与混凝土基层粘结行为研究

Study of Bonding Behavior between CFRP Sheet and Concrete

通过自行设计的试验方法,研究了30组粘贴有碳纤维增强塑料布(CFRP布)的混凝土试件粘结界面的破坏形态、粘结应力和碳纤维增强塑料布应变分布特性以及粘结破坏的发展过程.结果表明,粘结应力由碳纤维增强塑料布的加载端向自由端逐渐传递,破坏瞬时发生,破坏形式以剥离破坏为主;存在一个有效粘结长度,约为100 mm.研究结果说明自行设计的粘结试验方法有一定可行性,可为测定CFRP布-混凝土界面粘结强度指标提供新的思路.

Experiment of studying bonding performance was designed and 30 concrete specimens bonded with CFRP sheets were investigated. To verify the effect of interface bond properties, a detailed study were analyzed in term of the failure model of CFRP sheet-concrete interface, bond stress transfer process, CFRP strain distributions and developing process of debonding failure. The results show that the bond stress transfers from the load direction to the free end of CFRP gradually, which causes instantaneous failure of structure; most failure modes are debonding fail- ure in CFRP sheet-concrete interface and the effective bond length can be observed to be about 100 mm. The test method designed by authors is also verified to be practicable through the resuits, which provides a new idea to obtain the bond strength of CFRP sheet-concrete interface.