Influence of solution concentration and temperature on the repair effect for electrophoretic deposition of rust-cracked reinforced concrete

Abstract

Electrophoretic deposition is a new method for the repair of rust-expanded cracked reinforced concrete, which needs high performance epoxy resin repair solution. Selecting an appropriate solution concentration and temperature, clarifying the molecule electrophoretic deposition rule in the repair process, and revealing the influence mechanism of solution concentration and temperature on the repair effect will help maximize the application potential of the proposed method and control repair costs. In this study, four high-performance epoxy resin solutions with different concentration and temperature were prepared. The molecule electrophoretic deposition rule during the repair process was explored via macroscopic observation, mass increment, and resistance tests. The influence mechanism of solution concentration and temperature on the repair effect is discussed using microscopic observations combined with theoretical analysis. The results show that the waterproofing, carbonation resistance, and stray current erosion resistance of repaired specimens improve as the solution concentration increases. With the increase of solution concentration, the number of molecules per unit volume and the current density between electrodes increased, so the repair speed was faster and the repair effect was better under the condition of high concentration. The high temperature reduced the viscosity of the repair solution, which was conducive to the rapid deposition of molecules in the solution on the surface of the specimen at the early stage of the repair, but was not conducive to the film formation of epoxy resin on the surface of the specimen. Therefore, the waterproof and carbonization resistance of the repaired specimen decreased after the temperature increased.