ACOUSTIC METHODS FOR STRESS MEASUREMENTS IN STRUCTURES

PREDICTION OF CATASTROPHIC AND COSTLY FAILURES IN STRUCTURALCOMPONENTS HAS BEEN HAMPERED BY THE INABILITY TO MEASURE STRESS LEVELS IN CRITICAL COMPONENTS WITH ACCURACY. THIS PROPOSAL DESCRIBES THE STEPS NEEDED TO DEVELOP A STRESS MEASUREMENT SYSTEM THAT RELIES ON ULTRASONIC (ACOUSTOELASTIC) WAVE MEASUREMENTS. THE RECENT ADVANCEMENTSMADE IN THE USE OF CRITICALLY REFRACTED LONGITUDINAL WAVES (CRLW), COUPLED WITH THE EXPANSION OF COMPUTER-ASSISTED ULTRASONIC DETECTION SYSTEMS, HAVE GIVEN IMPETUS TO THIS PROPOSAL. THIS STUDY INVOLVES THE ANALYSIS OF THE CRLW PHENOMENA, IDENTIFICATION OF STATE-OF-THE-ART SUPPORT APPARATUS, EXPERIMENTAL VERIFICATION OF FUNDAMENTAL PREMISES, AND THE DEVELOPMENT OF A DESIGN SPECIFICATION FOR A STRESS ANALYSIS SYSTEM.