华南理工大学学报(自然科学版) ›› 2009, Vol. 37 ›› Issue (8): 76-82,88.

• 土木建筑工程 • 上一篇    下一篇

碳纤维布抗弯加固钢筋混凝土梁的耐火性能试验

吴波 万志军   

  1. 华南理工大学 亚热带建筑科学国家重点实验室, 广州 广东 510640
  • 收稿日期:2008-08-17 修回日期:2008-10-29 出版日期:2009-08-25 发布日期:2009-08-25
  • 通信作者: 吴波(1968-),男,博士,研究员,主要从事结构抗灾研究. E-mail:bowu@scut.edu.cn.
  • 作者简介:吴波(1968-),男,博士,研究员,主要从事结构抗灾研究.
  • 基金资助:

    国家“十一五”科技支撑计划子课题(2006BAJ03A03-12);教育部科学技术研究重点项目(108106);教育部博士学科点专项科研基金资助项目(20060561014);亚热带建筑科学国家重点实验室重点研究项目(2008ZA10)

Experimental Investigation into Fire Resistance of Reinforced Concrete Beams Strengthened in Flexure with Carbon Fiber Sheets

Wu Bo  Wan Zhi-jun   

  1. State Key Laboratory of Subtropical Building Science, South China University of Technology, Guangzhou 510640, Guangdong, China
  • Received:2008-08-17 Revised:2008-10-29 Online:2009-08-25 Published:2009-08-25
  • Contact: 吴波(1968-),男,博士,研究员,主要从事结构抗灾研究. E-mail:bowu@scut.edu.cn.
  • About author:吴波(1968-),男,博士,研究员,主要从事结构抗灾研究.
  • Supported by:

    国家“十一五”科技支撑计划子课题(2006BAJ03A03-12);教育部科学技术研究重点项目(108106);教育部博士学科点专项科研基金资助项目(20060561014);亚热带建筑科学国家重点实验室重点研究项目(2008ZA10)

摘要: 通过一根未加固钢筋混凝土梁及5根碳纤维布抗弯加固钢筋混凝土梁的三面受火试验,探讨厚涂型防火涂料的厚度、荷载比、碳纤维布加固量等因素对碳纤维布抗弯加固钢筋混凝土梁耐火性能的影响.结果表明:高温下该类构件的破坏形态大致可分为受弯破坏和弯剪破坏两类,常温下发生弯曲破坏的加固构件有可能在高温下出现破坏形态的转变;虽然加固构件所承受的荷载明显大于未加固构件,但由于防火涂料的保护,其耐火极限仍大于后者;碳纤维布加固量增加有可能导致加固构件的耐火极限延长,同时还可能涉及破坏形态的转变.通过科学合理地设置防火保护层,碳纤维布抗弯加固钢筋混凝土梁的耐火性能完全能够满足实际工程需要.

关键词: 碳纤维布, 抗弯加固, 钢筋混凝土梁, 耐火极限

Abstract:

Three-side fire tests of one unstrengthened reinforced concrete (RC) beam and five RC beams strengthened in flexure with carbon fiber sheets (CFSs) were carried out to reveal the influences of such factors as thicklayered fire coating thickness, load ratio and CFS-strengthening ratio on the fire resistance of the strengthened beams. Test results show that ( 1 ) the failure modes of the strengthened beams at high temperature can be classified as a flexure failure mode and a flexure-shear one ; (2) the flexure failure of the strengthened beams at room temperature may change at high temperature; (3) as compared with the unstrengthened beam, the strengthened beams with higher load are of stronger fire resistance due to the existence of fire coating; and (4) the increase of the strengthening ratio may result in the improvement of fire resistance and the change of failure mode. It is thus concluded that, by reasonably setting the fire insulation layer, the fire resistance of RC beams strengthened in flexure with CFSs well satisfies the requirements of practical engineering.

Key words: carbon fiber sheet, flexual strengthening, reinforced concrete beam, fire resistance