高强材料置换低强灰缝提高砖砌墙体承载力的研究

Research on Low-Strength Joint Mortar Replaced by High-Strength Materials to Increase Carrying Capacities of Existing Brick Walls

摘要: 国内早年建造的大量砖混结构中，相对现行相关规范要求，墙体因灰缝砂浆抗压强度过低导致受压与抗剪承载力明显不足为主要缺陷，对其继续长期安全使用有不利影响。研究表明，用高强材料置换这些墙体各灰缝的部分低强砂浆，提高灰缝砂浆的折算平均强度，可显著增大墙砌体的受压与抗剪承载力，以此改善整体结构的抗震性能。基于《砌体结构设计规范》GB 50003-2011，对该砖墙加固方法进行了深入分析，提出了墙体截面低强灰缝置换深度的计算方法，说明了该方法的适用条件与构造要求，给出了加固设计算例。用高强材料置换低强灰缝加固墙体简便易行，能较好满足加固工程中一些特定需求，可作为现有砌体加固技术的补充供砖混结构加固设计与施工参考。

Abstract: For most of early brick structures, due to strength insufficient of mortar joints in their walls, it is the major defect that compression capacity and shear capacity of the walls are clear lower than the requirement of current design code, so the long-term and safe use of them may not be determined. Research shows that the wall capacities can be added obviously and the seismic performance of brick structures including the detective walls can be improved jointly, in way of increasing average conversion strength of the mortar joints, from outer part of low strength joint mortar replaced by high strength materials. Based on Code for Design of Masonry Structures GB 50003-2011, the wall reinforcement method is analyzed deeply, the replace depth of low strength mortar joints is proposed, the suitable conditions and construction requirements are explained, the application example is given in this paper. As the complement of current similar techniques and the reference to reinforcement design and construction of masonry structures, the new method is easy to use, and also can meet some special needs of these brick structures to be reinforced.