Cracking Mechanism and Repair Techniques of Epoxy Asphalt on Steel Bridge Deck Pavement

Epoxy asphalt concrete is widely used for long-span steel bridge deck pavement in China. Because of the heavy traffic load and extreme climatic conditions, epoxy asphalt deck pavement tends to develop cracks, debonding, and potholes and needs reconstructing typically after 5 to 10 years. Research was performed on the cracking mechanism under both traffic and thermal loads, with the aim of finding the best sealing material. The performances of various crack-sealing materials, including workability, mechanical property, and durability, were evaluated. Test methods such as the simplified penetration ability test and bending fatigue test were employed for rating the crack-sealing materials. Experimental results revealed that the traditional crack-sealing materials, such as bitumen modified with styrene–butadiene–styrene, rubber bitumen, bitumen emulsion, and solvent bitumen, cannot meet the requirements for repairing epoxy asphalt on long-span bridge decks because of the low penetration ability and low adhesive strength. Results showed that cracks could be repaired well with epoxy resin–sealing materials, which showed great penetration ability, high bond strength, large deformation capacity, and short curing time.