CFRP网格-聚合物水泥砂浆加固RC梁的#br# 抗剪性能与计算公式

为揭示不同网格单位加固量对碳纤维增强复合网格(carbon fiber reinforced polymer grid，简称CFRP grid) 聚合物水泥砂浆(polymer cement mortar，简称PCM)复合加固钢筋混凝土(reinforced concrete，简称RC)梁抗剪性能的影响，构建CFRP网格-PCM加固RC梁的承载力计算方法，文章首先对7根采用CFRP网格 PCM复合加固RC梁进行四点弯曲静力加载试验，并在试验研究的基础上，提出基于横竖双向网格实际抗剪贡献的CFRP网格-PCM加固RC梁的承载力计算公式。研究结果表明：采用CFRP网格-PCM复合加固RC梁能显著提高其抗剪承载力，其中CFRP网格对于抗剪承载力的提高发挥主要作用，而PCM仅起到黏结剂的作用；加固梁的抗剪承载力与CFRP网格单位加固量呈正相关，但CFRP网格的协同变形性与CFRP网格单位加固量呈负相关；所提出的抗剪承载力计算公式与试验结果吻合良好。

Shear strengthening effect and analytical model of RC beams #br# reinforced by CFRP grid-PCM

In order to reveal the effect of different reinforcement amount of grid unit on the shear behavior of reinforced concrete (RC) beams strengthened by carbon fiber reinforced polymer grid (CFRP grid) polymer cement mortar (PCM) and to establish the calculation method for the bearing capacity of RC beams strengthened by CFRP grid-PCM, seven RC beams strengthened with CFRP grid-PCM were tested under four-point bending static loading. Based on the experimental results, a formula for calculating the bearing capacity of RC beams strengthened with CFRP grid-PCM is proposed, which is based on the actual shear contribution of transverse and vertical bidirectional grids. The results show that CFRP grid-PCM composite reinforcement can significantly improve the shear capacity of RC beams, in which the CFRP grid plays a major role in improving the shear capacity, while PCM only acts as a binder. The shear capacity of strengthened beams is positively correlated with the unit reinforcement amount of CFRP grid, but the cooperative deformation of CFRP grid is negatively correlated with the unit reinforcement amount of CFRP grid. The proposed formula is validated through the comparisons between the prediction and the measured shear capacity of RC beams strengthened with CFRP grid-PCM.