Abstract: The hydraulic structure in the high cold area is exposed to high altitude, strong ultraviolet radiation, cold winter and large temperature difference for a long time, which is more prone to crack, leakage and damage, as well as freeze-thaw damage, corrosion, carbonation, steel corrosion, erosion and other deterioration problems than other areas, which seriously affects the safe operation of the project. The weathering resistance of epoxy mortar was studied by indoor UV wet heat aging, freeze-thaw cycle and natural aging in Tibet. The results showed that the modified epoxy mortar did not crack after ultraviolet and wet heat accelerated aging for 2000 h, and the tensile strength retention rate was 74%. The frost resistance grade can reach F250; After 960d of natural aging, the color of the coating was slightly changed, and the surface was not powdered. The material was used for surface protection and repair of the stilling pool of the spillway tunnel of Laluo Water Conservancy project in Tibet Province. After more than 4 years of service, the modified epoxy mortar exhibited excellent anti-freezing, anti-ultraviolet and other weather resistance properties, and also provided good application potential for similar engineering applications in high-cold areas.

Key words: alpine regions, hydraulic structure, epoxy mortar, weather resistance, engineering application