Journal of the Korean Wood Science and Technology

The Korean Society of Wood Science & Technology (한국목재공학회)
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Estimation of Depth Effect on the Bending Strength of Domestic Japanese Larch Structural Lumber using Weibull Weakest Link Theory

  • Received : 2014.01.08
  • Accepted : 2014.01.28
  • Published : 2014.03.25
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Abstract

The depth effect on bending strength of Japanese larch structural lumber was investigated by using the published data of two different depth lumbers with the same length. Depth effect parameters were derived from Weibull's weakest link theory and compared to the results from other researches. Depth effect on bending strength was significant for No.1 and No.3 lumber, but not insignificant for No.2 lumber. Calculated value of the depth effect adjustment factors was 0.21, 0.11 and 0.22 by lumber grade, respectively. These results were similar to those results from previous researches and supported depth effect on bending strength of lumber. An apparent depth adjustment factor has been proposed to 0.2 in the literatures. Based on this study, depth adjustment factor was considered to 0.2 as a conservative optimum design value that should be incorporated in domestic building code (KBC) for structural lumber.

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References

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