Journal of the Korean Wood Science and Technology

The Korean Society of Wood Science & Technology (한국목재공학회)
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Development of Knot Quantification Method to Predict Bending Strength Using X-ray Scanner

  • Oh, Jung-Kwon (Department of Forest Sciences, Seoul National University) ;
  • Kim, Kwang-Mo (Department of Forest Products, Korea Forest Research Institute) ;
  • Lee, Jun-Jae (Department of Forest Sciences, Seoul National University Research Institute for Agriculture and Life Sciences)
  • Received : 2008.08.18
  • Accepted : 2008.09.09
  • Published : 2008.09.25
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Abstract

This study was aimed to develop the knot quantification method to predict bending strength, using x-ray scanner. The bending strength prediction model was proposed in this paper. The model was based on Knot Depth Ratio (KDR) and closely-spaced knot was taken into account. The previous paper reported that KDR is the ratio of the knot and transit zone to the lumber thickness. Even though KDR involves transit zone, it was verified that the ratio of the moment of inertia for knot to gross cross section ($I_k/I_g$) based on KDR was a good predictor for bending strength of lumber. To take closely-spaced knot into account, a projection method was also proposed. This projection method improved the predictive accuracy significantly. It showed coefficient of determinant of 0.65 and root mean square error (RMSE) of 9.17.

Keywords

References

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