MODAL ANALYSIS OF THE PIEZOELECTRIC GENERATION OF ULTRASONIC GUIDED WAVES FOR NDT OF CYLINDRICAL STRUCTURES

摘要

Civil engineering infrastructures contain elements like rods, pipes, cable strands, etc, which must be examined periodically to guarantee their integrity and safety. One of the oldest and most reliable methods for Non Destructive Testing (NDT) is based on the use of ultrasonic signals [1]. Recently, the use of ultrasonic guided waves for testing of large structures has gained much attention. The main advantages [2] of travelling waves over point-to-point inspection are that none, or minimal, alteration of the structure is required; that in situ operation can be achieved, sometimes without need to remove insulation; and that access to large portions of the structure is obtained from a single location. These features result in important time and cost savings for the inspection process.