Internal longitudinal damage detection in a steel beam using Lamb waves: Simulation and test study

Lamb waves are one of the promising tools to detect damage in aircraft structures. They can be generated in aircraft structures by piezoelectric actuators, propagate a long distance, and be picked up by several types of sensors. The waves can be easily distorted and attenuated by damage. In this study, internal longitudinal damage in a beam structure is experimentally and numerically detected. In order to create longitudinal Lamb waves, a unidirectional piezoelectric actuator is used. Plane strain models and three-dimensional solid models are developed, and dynamic simulations are performed using ABAQUS/Explicit. Lamb wave signals picked up by multiple sensors through the experiment are compared with the simulation results. Two internal notch damages are detected and the damage locations are estimated with the Lamb wave signals.