双层打包带加固RC梁的受力性能试验研究

Experimental study on mechanical performance of reinforced concrete beams strengthened with double-layer packing belt

为了减少打包带加固层与钢筋混凝土梁的剥离破坏,提出双层打包带加固方法。分别对未加固、单层打包带加固和双层打包带加固的RC梁进行正截面受弯和斜截面受剪试验,试验结果表明打包带加固未改变RC梁的破坏形态,但单层打包带加固RC梁的破坏较严重,加固层有水平裂缝,局部加固层剥落,发生剥离破坏,双层打包带加固梁的破坏程度最轻,加固层与基层整体性好,未出现水平裂缝和剥离破坏;打包带加固提高了梁抗弯和抗剪承载力,延缓了破坏过程,增加了构件延性,双层打包带加固梁性能最好。研究表明双层打包带加固可有效减少打包带与梁主体的剥离破坏,且加固效果更好。

In order to reduce the debonding failure of the interface between the packing belt reinforcement layer and the reinforced concrete beam,a reinforcement method of double-layer packing belt is proposed.The bending test of normal section and shear test of oblique section are carried out respectively on three beams,which are not reinforced,and reinforced with single-layer packing belt and reinforced with double-layer packing belt.The test results show that the packing belt reinforcement does not change the failure mode of RC beams,but the damages of RC beams strengthened with single-layer packing belt are more serious,horizontal cracks appear in the reinforcement layer,local mortar reinforcement layer peeled off,and debonding failure occurs.While the damage degree of the beams strengthened with double-layer packing belt are the least,the integrity of reinforcement layer and base layer are good,the horizontal cracks do not appeare in the reinforcement layer,and debonding failure does not find.The flexural and shear bearing capacity of the beams reinforced with packing belt are improved,the failure process are delayed,the ductility of the member are increased.The performances of the beam strengthened with double-layer packing belt are the best.The results show that the reinforcement method of double-layer packing belt can effectively reduce debonding failure,and achieve better reinforcement effect.