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Wood Science and Technology

, Volume 32, Issue 6, pp 393–402 | Cite as

Determination of shear modulus on construction size timber

  • F. Divos
  • T. Tanaka
  • H. Nagao
  • H. Kato
Originals

Abstract

Shear modulus determination of construction size timber was examined. Three different Techniques were used: torsional vibration, simultan E&G, and variation of span technique. We found that the simultan E&G technique is quite sensitive to the error of natural frequency determination and provides only an estimate for G. Better shear modulus determinations are the static and torsional techniques, but the torsional technique is most precise. The torsional vibration technique can be a good solution for shear modulus determination in an industrial environment because it provides quick and precise etermination, but standardization of the method would first be necessary. We found a high correlation coefficient (0.80) between the screw withdrawal resistance and shear modulus of 2 by 4 timber. Based on this result it is possible to estimate the shear modulus of timber even if the timber is installed in a structure.

Keywords

Shear Modulus Timber Torsional Vibration Frequency Determination Industrial Environment 
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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References

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Copyright information

© Springer-Verlag 1998

Authors and Affiliations

  • F. Divos
    • 1
  • T. Tanaka
    • 2
  • H. Nagao
  • H. Kato
    • 3
  1. 1.University of SopronSopronHungary
  2. 2.Forestry and Forest Products Research InstituteIbarakiJapan
  3. 3.Timber LaboratoryForestry and Forest Products Research InstituteTsukubaJapan

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