预应力碳纤维增强复合材料加固钢梁的耐久性能研究综述

A Review of Durability Research of Notched Steel Beams Reinfoned with Prestressed CFRP

疲劳损伤是钢桥最常见病害之一,预应力碳纤维增强复合材料(CFRP)能有效抑制裂纹扩展,延长结构服役寿命。预应力CFRP加固钢梁中,CFRP与钢界面作为主要的传力路径,保证了加固后结构的力学和耐久性能。在疲劳和湿热环境作用下,CFRP与钢界面的黏结性能发生劣化,导致加固后结构的力学性能退化。基于已有研究,总结了不同预应力加固系统设计下,钢梁的静载和疲劳性能的测试结果,以及环境因素对结构性能的影响机理。同时整理了预应力CFRP加固受损钢梁的界面主应力和黏结界面的能量释放率公式;并提出疲劳荷载和湿热环境作用下加固钢梁的承载力折减系数和寿命预测方法,以及考虑界面耐久性的结构加固设计思路。

Fatigue cracking is one of the most common issue that damages the serviceability of steel bridges.Prestressed carbon fiber-reinforced polymer(CFRP)materials can effectively inhibit crack propagation,thereby extending the service life of structures.In prestressed CFRP-reinforced steel beams,the interface between CFRP and steel interface serves as the primary load transfer path,ensuring the mechanical properties and durability of the reinforced structure.However,under the influence of fatigue and hygrothermal environments,the bonding performance of the interface between CFRP and steel may tend to degrade,leading to the degradation of mechanical properties in the reinforced structure.This paper summarized the results of static and fatigue performance tests of steel beams with different prestressed strengthening system design schemes,as well as the degree of influence of environmental factors on structural performance,based on existing research.Additionally,this paper compiled formulas for calculating the interface principal stress and energy release rate of damaged steel beams reinforced with prestressed CFRP,and proposed methods for predicting the bearing capacity reduction coefficient and service life of reinforced steel beams under fatigue loading and hygrothermal environments,as well as structural reinforcement design strategies considering interface durability.