Q. Underwater problems in bridge construction?

The major bridge construction materials are steel and concrete. In the past, stone and brick masonry, with lime mortar as binding agent, have been used extensively for building bridges. Cast iron piles have been used as substructure in many bridges. These materials are prone to different types of failure and, therefore, require different inspection strategies. The major problem in steel bridges is corrosion. Concrete bridges are susceptible to spalling and scour. Bridges built in masonry have the problem of deterioration of brick / stone elements accompanied with loss of mortar. Aquatic environment has significant effects on bridges in addition to those mentioned above. Heavy current is especially destructive. Floods cause damage from rapidly moving water as well as from the impact of large moving debris. The bridge substructure can also get damaged due to accidental man inflicted causes and earthquakes.