为了进一步研究嵌入式CFRP板条对混凝土梁受剪承载力的增强效果,对以往研究成果进行分析总结,提出两种新型的嵌入式受剪增强方式:槽形CFRP板条正向垂直和侧向平行嵌入。试验共设计制作2组4根CFRP嵌入式增强梁,两个对比梁。试验梁采用四点加载,研究CFRP板条的嵌入方式、间距和配箍率对受剪承载力提高的影响,同时分析CFRP板条强度的发挥程度,增强梁的破坏形态以及斜裂缝开展规律。基于破坏形态,对比已有的计算方法,提出CFRP板条抗剪贡献计算方法。研究结果表明所提出的两种嵌入式槽形CFRP板条能够更加充分地利用CFRP的强度,尤其是侧向平行嵌入方式,能够使嵌入式增强梁的受剪承载力提高更为显著;CFRP抗剪贡献计算方法能够适用非剥离破坏形态,具有较高的精度,不过该公式仍需进一步完善才可适用于普遍情况。
The shear behaviour of RC beams shear strengthened with embedded groove-shape CFRP laminates was investigated, in order to strengthen the shear capacity of RC beams in both the perpendicular and the longitudinal directions, respectively, considering previous research results, Two groups of beams, including four NSM strengthened beams and two control beams, were designed and tested under four-point loading. The influence factors of shear capacity, such as the mounting style, the space of CFRP laminates and the ratio of stirrups, were discussed, respectively. The efficiencies of CFRP strength, the failure modes and the diagonal crack patterns were compared and analyzed. Furthermore, the prediction formula of CFRP shear contribution was derived in terms of failure modes, and comparison with previous methods compared. The results indicate that CFRP strength could be utilized more sufficiently with groove-shape CFRP laminates, especially when using parallel mounting style, a more prominent shear capacity improvement of the strengthened beams could be achieved. The prediction formula of CFRP shear contribution is applicable to bond failure mode with preferable precision. Further research would focus on developing this formula for common cases.