磷酸钾镁水泥砂浆与混凝土粘结抗剪性能试验研究

Experimental study on shearing bonding behavior between magnesium potassium phosphate cement mortar and concrete

以双面剪切试验研究磷酸钾镁水泥(MKPC)砂浆与旧混凝土粘结抗剪性能,试验变化因素包括钢丝刷清洗浮灰、机械凿毛去浮浆、人工凿毛等三种旧混凝土表面处理方式,以及MKPC净浆销栓、加筋MKPC销栓和钢筋销栓三种植筋加固方法,对比分析各组试件的界面粘结抗剪强度和剪切破坏形貌。结果表明,对旧混凝土表面进行人工凿毛并露出骨料能较大幅度地提高界面粘结抗剪强度;加筋MKPC销栓能明显提高界面粘结抗剪强度,其效果接近于钢筋销栓,并具有明显的可操作性和经济性。

Shear bonding behavior between magnesium potassium phosphate cement（ MKPC） mortar and old concrete is studied by double shear experiment. The influence factors include three kinds of old concrete surface treatment such as cleaning dirt by steel wire brush,mechanical chiseling to eliminate laitance and manual chiseling as well as three kinds of reinforcement methods such as MKPC paste pin,reinforced MKPC pin and reinforcement dowel bar. The interfacial shear bonding strength and shear failure morphology of each specimen were compared and analyzed. Results show that,interfacial shear bonding strength can be greatly improved by manual chiseling to expose aggregate on the surface of old concrete. The reinforced MKPC pin can obviously improve the interfacial shear bonding strength,the effect is close to the rebar pin,and has obvious operability and economy.