Vibration Testing for the Evaluation of the Effects of Moisture Content on the In-Plane Elastic Constants of Wood Used in Musical Instruments

  • M. A. Pérez Martínez
  • P. Poletti
  • L. Gil Espert

Abstract

The present work provides an experimental-numerical investigation into the effects of moisture content on the in-plane elastic constants of wood for the specific use of the construction of soundboards of musical instruments. The vibrational behavior of a rectangular plate of spruce has been observed using vibration testing under different humidity conditions. The use of a nondestructive test method permits direct examination of a material sample which will eventually become part of a real instrument. The proposed approach is intended to minimize the difference between the numerical and experimental dynamic response through an iterative process, which allows identifying the elastic characteristics of wood specimens. It has been demonstrated that the vibrational behavior of timber varies considerably with variations in humidity. However, not all elastic properties are equally affected by such changes. The most significant variation is found in the transverse elastic modulus, and consequently in resonance modes associated therewith.

Keywords

Mode Shape Rectangular Plate Frequency Response Function Musical Instrument Free Boundary Condition 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Springer Science+Business Media B.V. 2011

Authors and Affiliations

  • M. A. Pérez Martínez
    • 1
  • P. Poletti
    • 2
  • L. Gil Espert
    • 3
  1. 1.Department of Strength of Materials and StructuresUniversitat Politècnica de CatalunyaBarcelonaSpain
  2. 2.Department of SonologyEscola Superior de Música de CatalunyaBarcelonaSpain
  3. 3.Laboratori per a la Innovació Tecnològica d’Estructures i MaterialsUniversitat Politècnica de CatalunyaBarcelonaSpain

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