Silicone Resin Enclosing Method Applied for the Maintenance of Steel Bearings

Abstract

Recently, the corrosion of steel bearings of bridges due to leakage of water from expansion joints has been a serious issue in Japan, affecting the lifetime of newly constructed and existing bridges. Particularly in snowy and cold regions, leaking water-containing chloride ion that remains on the pavement surface from spraying of deicing agents is the main corrosion factor of steel bearings. In this study, a transparent elastic silicone resin was applied for enclosing the steel bearing in order to control and monitor the corrosion and prevent deterioration. This newly developed maintenance method using silicone resin is effective due to the following characteristics: (1) by enclosing with silicone resin, corrosion factors such as intrusion of water and chloride ion are perfectly prevented, (2) the high transparency of silicone resin enables monitoring and thus allowing preventive action against any possible corrosion of steel bearings, and (3) due to high flexibility and deformability of the resin, the function and movement of the steel bearings are not restricted.