纤维格栅对新/旧水泥混凝土黏结性能的影响

摘要

为了研究纤维格栅类型、旧水泥混凝土与纤维格栅表面处理状况、粗集料最大粒径对新/旧水泥混凝土黏结劈拉强度的影响,对10组150 mm×150 mm×150 mm的新/旧水泥混凝土黏结立方体试块进行劈拉试验.分析了试件的劈拉破坏过程,探讨了纤维格栅与新/旧水泥混凝土的黏结机理.结果表明:采用网格尺寸为5 mm的玄武岩纤维格栅时新/旧水泥混凝土的黏结劈拉强度最大,旧水泥混凝土与纤维格栅表面处理状况对新/旧水泥混凝土黏结劈拉强度有较大的影响,而粗集料最大粒径对新/旧水泥混凝土黏结劈拉强度影响较小.%In order to study the influence of fiber gird type, surface treatment of old cement concrete and fiber grid, coarse aggregate limiting grain size on splitting tensile bonding strength between new and old cement concrete, ten groups of specimens with dimension of 150 mm × 150 mm × 150 mm were tested for splitting tensile strength. The splitting tensile failure process was analyzed, then the mechanism of bonding between fiber grid and new and old cement concrete was discussed. The result demonstrates that the splitting tensile bonding strength becomes maximal when the basalt fiber grid with dimension of 5 mm is used, the surface treatment of old concrete and fiber grid have great influence on splitting tensile bonding strength between new and old cement concrete, but the coarse aggregate limiting grain size have little influence on it.