碳纤维布加固火灾后钢筋混凝土连续梁的试验研究  

Experimental Research on Carbon Fiber Reinforced Polymer Sheets Strengthened Fire-damaged Reinforced Concrete Continuous Beams

作　　者：项凯[1] 余江滔[2] 陆洲导[2] 郭金纯[2] 

机构地区：[1]公安部天津消防研究所,天津300381 [2]同济大学结构工程与防灾研究所,上海200092

出　　处：《四川大学学报（工程科学版）》2010年第2期52-57,共6页Journal of Sichuan University (Engineering Science Edition)

基　　金：国家自然科学基金资助项目(50578126)

摘　　要：研究碳纤维加固受火后混凝土连续梁力学性能的变化。制作4根混凝土T形连续梁,其中1根为常温无加固对比梁,采用ISO834标准升温曲线对3根梁进行火灾试验。受火后1根梁为无加固对比梁,2根梁采用碳纤维布加固,4根梁采用相同的加载方式进行静载试验,比较4根梁受力性能的变化。受火后梁的承载力、刚度和延性均有所下降,其中延性和刚度下降最为明显。受火后梁的内力重分布发生较大变化,受火梁的破坏模式与未受火梁有所区别。采用碳纤维布加固后梁的刚度和承载力均有提高,但是加固梁的延性继续降低,碳纤维布的加固方式对受火梁的内力重分布有一定影响。采用碳纤维加固可以提高受火后混凝土连续梁的承载力和刚度,但要考虑加固后梁延性的降低和受火后内力重分布的影响。The mechanical properties of Carbon Fiber Reinforced Polymer（CFRP） strengthened fire-damaged concrete continuous beams was tested.Four reinforced concrete T-beams were constructed.One beam was normal temperature control beam,and others were heated under ISO834 curve.One beam was fire damaged control beam,and two beams were strengthened with CFRP sheets.The same test set-up was used to loading tests of four beams.The results showed that bearing capacity,rigidity and ductility of fire-damaged beams were become lower than the normal temperature beam.Ductility and rigidity of beams were dropped sharply,and the way of moment redistribution of beam changed seriously for the influence of fire.The fire-damaged beams had different failure mode compared to the normal temperature beam.External strengthening with CFRP sheets was found to increase bearing capacity and rigidity,but the ductility was dropped further.The way of strengthened position take some influence on moment redistribution of fire-damaged beam.Bearing capacity and rigidity were improved for CFRP strengthened fire damaged continuous beams,but the drop of ductility and moment redistribution after fire should be considered.

关 键 词：火灾 混凝土梁 碳纤维 弯矩重分布 

分 类 号：TU375.1[建筑科学—结构工程] TU317