Remote Acoustic Monitoring of Thin Laminates

Document type: Conference Papers
Peer reviewed: Yes
Full text:
Author(s): Etienne Mfoumou, Sharon Kao-Walter, Claes Hedberg
Title: Remote Acoustic Monitoring of Thin Laminates
Conference name: WCEAM-CM 2007
Year: 2007
Pagination: 1426-1433
ISBN: 978-1-901892-22-2
Publisher: COXMOOR
City: Harrogate, UK
Organization: Blekinge Institute of Technology
Department: School of Engineering - Dept. Mathematics and Science (Sektionen för teknik – avd. för matematik och naturvetenskap)
School of Engineering S- 371 79 Karlskrona
+46 455 38 50 00
Authors e-mail:,,
Language: English
Abstract: Understanding the change in material properties in time is necessary for in-service diagnosis of structures and prevention of accidents. Therefore, a new experimental technique for evaluating Young’s (or elastic) modulus of a vibrating thin sheet from a dynamic measurement is presented. The technique utilizes bending resonance from a remote acoustic excitation. Equations relating the natural frequencies to the mechanical properties are obtained, and Young’s modulus is subsequently determined experimentally using the implemented dynamic measurement method. Young’s modulus values from the dynamic test are then compared with those (static) obtained by a standard tensile test and those obtained by the theory of laminated materials. The proposed technique appears relatively simple and is applied in this paper to laminates initially having no (or negligible) bending stiffness, and used in packaging industries. This work emphasizes the feasibility of a remote condition monitoring of components in-service by evaluating changes in the material properties.
Subject: Mechanical Engineering\Structural Dynamics
Mechanical Engineering\Structural Mechanics
Keywords: Condition Monitoring, Vibration, Young’s modulus, Resonance, Acoustic, Non-Destructive Testing.