表层内嵌桁架螺旋肋筋加固混凝土梁抗弯试验研究  

Bending experiment of RC beams strengthened with near-surface mounted truss helical rib rebar

作　　者：曾宪桃[1] 任振华[2] 赵晋 丁亚红[2] 

机构地区：[1]湖南工程学院,湖南湘潭411104 [2]河南理工大学,河南焦作454003 [3]河南神马氯碱化工股份有限公司,河南平顶山467001

出　　处：《土木工程学报》2010年第1期64-69,共6页China Civil Engineering Journal

基　　金：河南省高校杰出科研人才创新工程项目(2007KYCZ006)

摘　　要：按正常配筋浇筑了18根钢筋混凝土梁,根据螺旋肋筋与钢筋连接方式的不同,在混凝土梁受拉区混凝土保护层内开槽,在槽内嵌入螺旋肋筋或螺旋肋筋与钢筋组成的桁架,用专用树脂对槽道进行充填,待树脂固化完成后,对梁进行弯曲试验。试验研究表明:内嵌螺旋肋筋及其与钢筋组合桁架加固后的混凝土梁,其极限承载能力、刚度及抗裂性能均有明显改善。随着嵌入加固量的增加,加固梁的极限承载能力得到明显提升,钢筋与螺旋肋筋的焊接点是薄弱环节,导致加固梁出现脆性破坏特征;与对比梁相比,内嵌1根螺旋肋筋加固的混凝土梁极限承载能力提高了35.1%和42.2%;内嵌2根螺旋肋筋加固的混凝土梁极限承载能力提高了73.3%和77.8%。Eighteen concrete beams were cast with normal reinforcement bars. According to different combinations of helical rib rebar and ordinary rebar, grooves are opened in the concrete cover of the tensile region in the concrete beams. Helical rib rebar or truss composed of helical rib rebar and ordinary rebar is inserted in the grooves and then filled with resin. Flexural experimental results indicate that the limit bearing capacity, rigidity and crack resistance of the beams strengthened with helical rib rebar and composite truss are all improved significantly. The juncture of helical rib rebar and ordinary rebar is the weak zone, which causes brittle failure in the strengthened beams. In comparison, the limit bearing capacity of the beam strengthened with one near-surface mounted helical rib rebar is increased by 35.1% and 42.2%, and the limit bearing capacity of the beam strengthened with two near-surface mounted helical rib rebars is increased by 73.3% and 77.8%.

关 键 词：混凝土梁 抗弯性能 试验研究 表层内嵌 螺旋肋筋 

分 类 号：TU375.4[建筑科学—结构工程]