碳纤维加固部分预应力损伤混凝土梁静力试验研究.pdfVIP

2007年 第 12期(总第 218期 ) 混 凝 土 理 论 研 究 Number l2 in 2007(Tota1 No．2l8) Concrete THE0RETICAL RESEARCH 碳纤维加固部分预应力损伤混凝土梁静力试验研究 童谷生 (华东交通大学 土建学院，江西 南昌330013) 摘 要：对碳纤维加固预应力混凝土纯弯梁进行了试验研究和理论分析。预制了7根部分预应力矩形截面混凝土试验粱，将其中的一根 梁作为对比梁，将4根梁在加固前预加荷载形成初始裂纹(损伤)，其它两根梁直接进行加固。研究了初始损伤对部分预应力梁加固效率的 影响；考虑了粘贴碳纤维层数对预应力加固后静承载力的影响。实验表明：高强纤维布可以有效加强微损伤预应力梁，与完好梁相比可以 忽略初损伤的影响，两层纤维布加固后静强度提高可达50％。 关键词： 碳纤维布；预应力混凝土梁；初始损伤；加固 中图分类号：TU528．572 文献标志码：A 文章编号： 1002—3550(2007)l2-0023—04 Static study of strengthening damaged prestressed concrete beam with carbon fiber reinforced plastic sheet TONGGu—sheng (School ofCivilEngineering andArchitecture，EastChina JiaotongUniversity，Nancheng 330013，China) Abstract： The flexural behavior and strength ofprestressed concrete beams strengthened witll CFRP were investigated experimentally and ana— lytically．Seven prestressed concrete beams were made to study the viability ofthe system．Four initial dam aged beam were made before tbey were strengthened，the other two beam were strengthened directly，and the final one is unstrengthened control beam．The Initial damage and number of FRPs layer is studied as effective parameters．The experiments show that flexural capacity and flexural stiffness of strengthened beam s were in— creased ，strengthincreases upto 50％ couldbeobtained whentwolayofFRPswerepasted． Key WOrds： carbon fiber sheets；prestressed concrete beam ；initial damage；strengthen (d=10-25 nllT1)作骨料I夕 加剂采用贵溪塔粉(FDN)，掺量为 0 引言 0．4％；水灰比为0．5，混凝土配合比为1：1．99：2．99(水泥：砂：碎 目前，碳纤维加固粱类构件研究主要集中在普通钢筋混凝 石)，浇注时视现场情况再进行适当调整。浇注时先放入钢筋骨 土梁加固工艺、加固后承载能力提高情况及相关机理的分析与