When should protective coatings be reapplied to steel bridges?

Protective coatings should be reapplied to steel bridges when the existing coating system shows signs of deterioration, such as rust, blistering, cracking, or loss of adhesion. Regular inspections should be conducted to monitor the condition of the coating. The timing of reapplication depends on the severity of the deterioration and the environmental conditions to which the bridge is exposed. If rust is present, it should be removed and the steel surface prepared before applying a new coating. Reapplication should also be considered if the coating has reached the end of its expected service life, even if there are no visible signs of deterioration. Prompt reapplication of protective coatings is essential to prevent corrosion of the steel and maintain the structural integrity of the bridge.