Repair and Retrofitting of Underwater Structures

Underwater structures such as bridge piers, offshore platforms, jetties, ports, dams, quay walls, pipelines, and submerged foundations form critical components of transportation, energy, and marine infrastructure systems. These structures are continuously exposed to highly aggressive environmental conditions including chloride-rich seawater, tidal fluctuations, wetting–drying cycles, chemical attack, biofouling, abrasion from sediments, and hydrodynamic forces. Over time, such exposure leads to deterioration mechanisms such as corrosion of reinforcement, steel section loss, concrete cracking and spalling, scour around foundations, fatigue damage, and material degradation. The inspection, maintenance, repair, and retrofitting of underwater structures present unique engineering challenges compared to above-water structures. Limited accessibility, poor visibility, water pressure, current forces, and the need for specialized diving or remotely operated equipment significantly complicate assessment and intervention processes. Moreover, repair materials and techniques must be compatible with submerged conditions, resistant to washout, and capable of gaining strength in wet environments.