Damage Detection Analysis Using Lamb Waves in Restricted Geometry for Aerospace Applications

<p>A goal of structural health monitoring (SHM) is to increase aircraft readiness through condition based maintenance (i.e. servicing an aircraft only when it is known to be necessary). The lead ziconate titanate (PZT) is a commonly used piezoelectric transducer that has shown potential to detect damage in aircraft structures without time consuming manual inspections. But many locations identified by the USAF for SHM have restricted geometries presenting difficulties using the PZT transducers successfully. One known fatigue location in an aircraft bulkhead has been selected as a basis to evaluate some of the challenges of using PZT transducers for SHM. The goal of this research is use analytical and experimental investigations to detect fatigue cracks in plates representing the restricted geometry of the aircraft bulkhead. This research shows that detecting closed fatigue cracks can be more challenging than detecting open cracks but that opening the cracks using an applied static load presents new challenges.</p><p>This work has been selected by scholars as being culturally important and is part of the knowledge base of civilization as we know it. This work was reproduced from the original artifact and remains as true to the original work as possible. Therefore you will see the original copyright references library stamps (as most of these works have been housed in our most important libraries around the world) and other notations in the work.</p><p>This work is in the public domain in the United States of America and possibly other nations. Within the United States you may freely copy and distribute this work as no entity (individual or corporate) has a copyright on the body of the work.</p><p>As a reproduction of a historical artifact this work may contain missing or blurred pages poor pictures errant marks etc. Scholars believe and we concur that this work is important enough to be preserved reproduced and made generally available to the public. We appreciate your support of the preservation process and thank you for being an important part of keeping this knowledge alive and relevant.</p>