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http://dx.doi.org/10.5658/WOOD.2013.41.5.432

Evaluation of Allowable Bending Stress of Dimension Lumber; Confidence Levels and Size-adjustment  

Pang, Sung-Jun (Department of Forest Sciences, College of Agriculture & Life Sciences, Seoul National University)
Lee, Jun-Jae (Department of Forest Sciences, Research Institute for Agriculture and Life Sciences, College of Agriculture & Life Sciences, Seoul National University)
Oh, Jung-Kwon (Department of Forest Sciences, Research Institute for Agriculture and Life Sciences, College of Agriculture & Life Sciences, Seoul National University)
Publication Information
Journal of the Korean Wood Science and Technology / v.41, no.5, 2013 , pp. 432-439 More about this Journal
Abstract
The aim of this study was to investigate the processes for evaluating the allowable bending stress. The confidence levels and the size-adjustment in standards were reviewed with experimental data. The results show that, (1) KS F 2152 was more strict than others overseas standards due to the higher confidence level. The 5% NTL of bending strengths by a method in KS F 2152 were lower than the overseas standards and more specimens were required for evaluating the structural properties according to KS F 2152. (2) Due to the absence of size-adjustment method in domestic standards, the specified size and the exponential parameters on the size-adjustment equation were reviewed by size factors. The specified size (width: 286 mm, length: 6096 mm), and the exponential parameters (w: 0.29, l: 0.14) will be suitable for developing the allowable bending stress in domestic standard. (3) The size adjusted allowable bending stresses of No. 2 grade Korean pine were lower than the allowable stresses tabulated in KBC even though less strict method (75% confidence level) to calculate 5% value was used. The allowable stresses tabulated in KBC are needed to be reviewed by continuous experimental data.
Keywords
confidence level; size-adjustment; lumber; allowable bending strength; size factor;
Citations & Related Records
Times Cited By KSCI : 5  (Citation Analysis)
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