Effect of interface-treatment for the unity and reliability on the interface between existing concrete and repair materials

为了提高在役钢筋混凝土梁的抗剪承载力，在梁的底部粘贴碳纤维布（CFRP）网格和聚合物水泥砂浆（PCM），研究了碳纤维布加固梁的抗剪粘结强度与粗糙度的关系、抗剪区的位移以及加固效果。剪切粘结强度与表面粗糙度成正比。进行了单元试件的拉拔试验，研究了喷碳纤维格栅PCM与混凝土的抗剪粘结性能。试验结果和数值分析结果表明，剪切粘结应力的承载区域从加载点附近的试件底部向试件上部移动。此外，它被证实，喷涂PCM和CFRP的组合是有效的加固既有钢筋混凝土梁。

The shear capacity in existing RC beams increases by attaching the carbon fiber reinforced plastic (CFRP) grids and the polymer cement mortar (PCM) to side areas of base concrete beams.In this study, the relation between shear bond strength and roughness, the shift of shear resisting area and the effect of strengthening of beam using CFRP were investigated. Shear bond strength was directly proportional to the degree of surface roughness. The pull-out tests of element specimens were conducted, to investigate shear bond behavior between existing concrete and sprayed PCM with a CFRP grid. From the experimental results and numerical analysis results, it was clarified that the bearing areas of shear bond stress shift from bottom of the specimen which is near the loading point to upper part of the specimen. Also, it was confirmed that the combination of sprayed PCM and CFRP were effective for strengthening existing reinforced concrete beams.