预应力SCFRP加固损伤箱梁抗弯性能研究  

Flexural Behavior of Prestressed SCFRP Reinforced Damaged Box Girders

作　　者：农升伟 罗文结[2] 李保军 郭馨艳[2] NONG Shengwei;LUO Wenjie;LI Baojun;GUO Xinyan(Guangxi Zhuang Autonomous Region Guixi Highway Development Center,Nanning 530001,China;School of Civil Engineering and Transportation,South China University of Technology,Guangzhou 510641,China;Guangxi Transportation Technology Group Co.,Ltd.,Nanning 530001,China)

机构地区：[1]广西壮族自治区桂西公路发展中心,广西南宁530001 [2]华南理工大学土木与交通学院,广东广州510641 [3]广西交通科技集团有限公司,广西南宁530001

出　　处：《安徽建筑大学学报》2024年第5期55-62,共8页Journal of Anhui Jianzhu University

基　　金：国家自然科学基金面上项目(12172134);国家留学基金委资助项目(202206155006)。

摘　　要：近几十年来,基础设施的老化和负荷加重加剧了其劣化现象。据统计,全国近一半出现病害的桥梁为空心混凝土桥。因此,采用合理高效的方法加固损伤箱梁,对其安全运行至关重要。本论文选取7根已退役空心箱梁作为研究对象,首先对其进行损伤度检测。随后采用不同预应力度钢丝—碳纤维增强复合材料(SCFRP)和碳纤维复合材料(CFRP)对不同损伤度的空心箱梁进行加固。通过加固箱梁现场加载试验以及DIC测量,分析了不同预应力度SCFRP、CFRP(S/CFRP)以及损伤度对加固结构承载力、裂纹以及S/CFRP—混凝土界面性能的影响。研究结果表明,施加预应力的S/CFRP可以有效减缓裂纹的扩展,且预应力度越高,加固后梁的抗弯承载力提升越显著。然而,高预应力度也可能加大S/CFRP—混凝土界面滑移量,增加界面剥离的风险。In recent decades,the aging of infrastructure and increased loads have exacerbated the deterioration of infrastructure.According to statistics,nearly half of the bridges nationwide that have developed defects are made of hollow box girders.Therefore,it is crucial to reinforce damaged box girders using reasonable and efficient methods to ensure their safe operation during service.This paper selected seven decommissioned hollow box girders as the research objects and first conducted damage detection on these girders.Subsequently,different levels of prestressed steel wire-carbon fiber reinforced polymer(SCFRP)and carbon fiber reinforced polymer(CFRP)were used to reinforce the hollow box girders with varying degrees of damage.Through on-site loading tests and DIC(Digital Image Correlation)measurements of the reinforced girders,the effects of different prestress levels of SCFRP and CFRP(S/CFRP)as well as damage levels on the load-bearing capacity,crack formation,and S/CFRP-concrete interface properties of the reinforced structures were analyzed.The research results indicate that prestressed S/CFRP can effectively retard crack propagation,and the higher the prestress level,the more significant the increase in the bending load capacity of the reinforced girders.However,high prestress levels may also lead to an increase in the slip at the S/CFRP-concrete interface,thereby increasing the risk of interface debonding.

关 键 词：预应力 SCFRP加固 空心箱梁 损伤 

分 类 号：TU375[建筑科学—结构工程]