Define Steel substructure - underwater inspection of bridge?
Steel is used as a structural material and as external protective cladding on concrete foundation elements. Steel foundation elements located in water, commonly H piles, or sheet piling can suffer distress in the form of corrosion. The corrosion can be especially severe when the bridge is located in salt water or brackish water. The most important factors influencing and providing corrosion are the presence of oxygen, moisture, chemicals, pollution, stray electrical currents, and water velocities.