DAMAGE INDICES EVALUATION FOR ONE-DIMENSIONAL GUIDED WAVE-BASED STRUCTURAL HEALTH MONITORING

Abstract

DAMAGE DETECTION IN STRUCTURES IS ESSENTIAL FOR MONITORING PARAMETERS THAT CAN AFFECT THE RELIABILITY OF THE ENGINEERING SYSTEM. THIS WORK EVALUATES THE EFFICIENCY OF RMSD, MAPD, COV, AND CCD DAMAGE INDICES (DIS) COMMONLY USED WITH TEMPORAL WAVE SIGNALS. A EULER-BERNOULLI BEAM WAS ASSUMED AS A GUIDED WAVE AND MODELLED BY THE SPECTRAL ELEMENT METHOD.  IT INCLUDES THE BACKGROUND FORMULATION OF THE THROW-OFF BEAM SPECTRAL ELEMENT, THE UNDAMAGED AND CRACKED BEAM SPECTRAL ELEMENT.  MOREOVER, THE DIS EXPRESSION IS PRESENTED, AND THE NORMALIZATION IS FORMULATED. NUMERICAL SIMULATION IS CONSIDERED HOMOGENEOUS BEAMS EXCITED BY A TONE BURST PULSE. THE DIS FOR A SINGLE CRACK POSITION AND A MAP VARYING CRACK DEPTH AND POSITIONS ARE CALCULATED WITH DETERMINISTIC AND RANDOM TEMPORAL SIGNAL RESPONSES DERIVED FROM NOISE ADDITION. RESULTS SHOWED THAT DAMAGE INDICES COULD IDENTIFY DAMAGE CONDITIONED TO THE PULSE APPLICATION POINT DISTANCE AND THE INFLUENCE OF NOISE IN THE ESTIMATION, WHICH TURNS THE ANALYSIS CLOSE TO PRACTICAL APPLICATIONS.