Reinforcement Technology Research On E-glass Textile Reinforced Fine Aggregate Concrete Sheets Used Magnesium-phosphate Cements

E-glass textile reinforced magnesium-phosphate cement based fine aggregate concrete(GTRC-M) sheet of beams, slabs, columns and other RC structure reinforcement member is a new reinforcement method. This method takes advantage of the low prices of the characteristics of E-glass fabric and our group developed modified magnesium phosphate cement has the initial setting time can be adjusted, low shrinkage, good compatibility, has good durability, wear resistance, high temperature performance and hardening substantially low alkaline, etc. Therefore the reinforcement method can significantly reduce the project costs while improving reinforcing performance, and provide new ideas and theoretical basis for fiber reinforced composite materials research and applications in the field of RC structure.In order to develop this kind reinforcement technology for practical application to provide the necessary relevant performance parameters and design theory,Specific research and research results are as follows:(1)Tensile mechanical properties and four-point flexural mechanical properties experimental research on GTRC-M sheet and GTRC-P sheet are performed under normal conditions and accelerated aging conditions. The experimental results show that the tensile and flexural strength of GTRC-M sheet specimens decrease was primarily due to magnesium phosphate cement matrix caused, rather than the glass fiber by corrosion during the aging process, indicating that the durability of the glass fiber composite materials can effectively improve by using magnesium phosphate matrix; The tensile and flexural strength of GTRC-P sheet specimens decrease was while the matrix strength gradually increased, indicating that glass fibers are corroded by ordinary portland cement.(2)The shear experiment research on GTRC-M sheet and the old concrete columns are performed in this paper,the effects of different interfacial techniques, ie, artificial chiseling,grooving, reinforced bar planting and old concrete strength on the shear properties are investigated, and its ultimate load and failure mode are studied. The best chisel roughness,anchorage rate, slotting rate etc the relevant practical design parameters are obtained; the bonding behaviour between GTRC-M sheet and old concrete are effectively improved by the above different interfacial techniques.(3)A new method with E-glass textile reinforced fine aggregate concrete sheets used magnesia-phophate cements is proposed for the strengthing reinforced concrete beams.Four strengthened beams and one no-strengthened beam is experimentally investigated.The failure pattern, crack development, relationship of load –deflection, relationship of load-steel strain are analyzed. While reinforced beam bonding interface stress theoretical analysisl,The flexural behavior to be affected by the number of textile layers is studied.The results indicated that the cracking loading, yield loading and ultimate loading of the strengthened beams are increased, and the ductility of the strengthened beams is reduced;Exists on the shear stress in the bonding interface, and is proportional to the section on bending moment; planting bar in mid span can improve failure pattern, increase the ultimate bearing capacity.(4)Based on experimental research, the calculation method of bending capacity of reinforced concrete beams are proposed,gives the relevant formula, without considering the impact reinforcement layer thickness, gives the relevant formula, the ultimate strength of fabric as the basis of reinforced concrete beams for the calculation of ultimate bearing capacity.