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Wood Science and Technology

, Volume 23, Issue 1, pp 95–108 | Cite as

Grading of construction timeber by ultrasound

  • J. L. Sandoz
Article

Summary

The resistance of spruce beams was characterized with the aid of nondestructive ultrasonic measurements. The modulus of elasticity and the modulus of rupture in flexure for beams of commercial sized section can be estimated by observing the speed of propagation of a longitudinal wave applied to the longitudinal axis of the beam. The use of simple ultrasonic equipment and two experimental transducers (in direct and dry contact) permit measurements to be performed in industry. The technique constitutes the basis of an objective concept for classification of sawn timber guaranteeing a better reliability and profitability with regard to the visual grading rules used in Western Europe.

Keywords

Europe Longitudinal Wave Timber Longitudinal Axis Good Reliability 
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-Verlag 1989

Authors and Affiliations

  • J. L. Sandoz
    • 1
  1. 1.EPFL-ÉcublensLausanneSnritrerland

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