Define Inspection of Pier or Abutment?
Inspection of pier/abutment may then be carried out as under:
i. Conduct visual inspection of the entire surface using up and down sweeping motion. If the surface is covered with marine growth, one of the segments should be thoroughly cleaned and examined particularly just below the waterline, mid point between waterline and mud line, and at mud line.
ii. Visually inspect this area for cracks, surface spalling, cavitation, mechanical damage, exposed reinforcing steel. Diver should be alert for any change in appearance of the concrete surface.
iii. Sound the cleaned area with a hammer to detect any loose layers of concrete/hollow spots in the structure. A sharp ringing noise indicates sound concrete. A soft surface will be detected not only by a sound change but also by a change in the rebound or feel of the hammer. A thud or hollow sound indicates a delaminated layer of concrete or internal voids.
iv. Descend, visually inspecting the structure and inspect in greater detail the base of the structure. Note down any signs of undermining by wave and current action. Record the water depth with any observation of damage on a Plexiglas plate.
v. Cracks found on the surface of the concrete structure should be given careful attention. Sketches should be made to show the length and direction of the cracks. Still and video photograph should be taken as they are helpful in later decision making.