Research Of Stability And Permeability Of Concrete Surface Durability Reinforcing Agent

Permeable durability reinforcing agent used for concrete surface is a material sealing surface of concrete, and it can permeate into inner of concrete and fill or block the pores of concrete surface with dry crystal or emulsoid generated by reaction between it and chemical compound in concrete. It is important for the protection of concrete structure.Considering stability of reinforcing agent and basing on theoretical analysis, three methods including thickening, dispersing large grains and separating large grains are used. The results show that thickening method has no effect on the stability of reinforcing agent, and method of dispersing large grains can improve storing stability of reinforcing agent. When the large grains more than 0.9μm are separated by method of separating large grains, storing stability of reinforcing agent can be solved.In order to improve the permeability and reinforcement of reinforcing agent, assistants and they dosages are studied when considering viscosity and economical efficiency of reinforcing agent. Two assistants, SZ and NBF, are studied in this paper, and the optimal dosages of them are 0.1% and 0.01% respectively. Adding assistant at optimal dosage, reinforcing agent has very strong permeability. Its permeating length into C20 concrete can be 12.5mm and 4.5mm into C30 concrete.Chloride ion permeability coefficient of C20 concrete and C30 concrete reduces after concrete surface is treated by reinforcing agent, and soakage reduced too. So the impermeability and carbonization resistance of concrete, especial C20 concrete, increase. Permeability test of concrete which surface is treated by reinforcing agent prove that it can improve durability of low strength concrete effectively.