Research And Technology On Bending Performance Of Fiber And Fabric Reinforced Potassum Magnesium Phosphate Cement Matrix Composites Reinforced Defected Beams

Magnesium potassium phosphate cement(MKPC) is a new cementitious material of early strength and fast hardening,compared with ordinary portland cement,MKPC has the advantages of low temperature setting,high bonding strength,dry shrinkage,abrasion resistance and frost resistance.Through these experiments,the surface bond property of the MKPC cement-based composites materials(this paper is all ―MKPC mortar‖) and old concrete,the tensile and bending properties of fiber and textile reinforced MKPC mortar sheets, and the anti bending test of two kinds of defect beams strengthened with fiber and textile reinforced MKPC mortar,the following conclusions can be obtained:(1) The best performance of interfacial bonding shear is MKPC cement mortar between the old concrete with artificial gouges. The shear strength of MKPC cement mortar reinforced with cement mortar is significantly improved by using a new type of reinforced MKPC cement paste. Using the sand mixture of MKPC can improve between new and old concrete adhesive tensile performance of the proliferation, but the interfacial agent on the MKPC mortar and the old concrete bonding interface tensile enhancement effect is not obvious.(2) The tensile strength of the short cut glass fiber reinforced MKPC mortar is better than basalt fiber, and the corrosion resistance of mortar can be improved. The composite reinforced MKPC mortar not only can improve the bending bearing capacity of the thin plate but also improve the effect of the toughening, And after aging of 80℃ in the water glass fiber fabric web will not corrode, only the matrix strength decreased.(3) Study on bending test of two kinds of different defect beams. After the ultimate load carrying capacity of the test beam at the beginning of damage 40%, the unloading of fiber, fabric reinforced MKPC mortar strengthening still has a substantial increase. However, if the length of the reinforcement layer too short may be shear failure. After the experimental beam in the reinforcement of the accelerated corrosion(corrosion rate of 5%),then use fiber MKPC mortar and fiber, fabric composite reinforced MKPC fiber mortar contrast and reinforcement can be found both for the ultimate bearing capacity of the beam has been improved, but use the reinforcement layer can improve the bonding ability of new and old concrete.The research work will promote the application of MKPC in the reinforcement engineering, and promote the development of new materials and new technology in engineering. It has positive significance to promote the development of MKPC composite materials.