关键词: 腐蚀, 纤维复合材料, 疲劳, 加固, 混凝土, 梁

Abstract:

The experimental results of the structural fatigue performance of corroded reinforced concrete (RC) beams repaired with fiber-reinforced polymer (FRP) sheets were summarized in this paper.Ten RC beam speci- mens (152×254×3,200mm) were constructed.One was neither strengthened nor corroded to serve as a refer- ence|three were corroded but not repaired|another three were corroded but repaired with U-shaped glass FRP sheets that wrapped the cross section of the specimen|and the remaining three were corroded and repaired with U- shaped glass FRP sheets for wrapping and carbon-fiber-reinforced polymer (CFRP) sheets for flexural strengthe- ning.The FRP sheets were applied after the main reinforcing bars were corroded to an average mass loss of 5.5%. Following FRP repair,some specimens were tested immediately to failure while the other repaired specimens were subjected to further corrosion before being tested to failure to investigate their long-term protecting performance.Re- inforcement steel pitting due to corrosion reduced the fatigue life significantly.The FRP wrapping had no significant effect on the fatigue performance,while using CFRP sheets for flexural strengthening enhanced the fatigue perform- ance significantly.The fatigue life of the retrofitting RC beams was increased with the decrease of the reinforcements stress amplitude.

Key words: corroded, carbon-fiber-reinforced polymer, fatigue, strengthening, concrete, beam