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http://dx.doi.org/10.5658/WOOD.2015.43.1.25

Review of Visual Grading and Allowable Stress Determination Methodologies for Domestic Softwood  

Kong, Jin Hyuk (Department of Wood Science and Engineering, Research Institute for Agriculture & Life Sciences, Chonnam National University)
Jeong, Gi Young (Department of Wood Science and Engineering, Research Institute for Agriculture & Life Sciences, Chonnam National University)
Publication Information
Journal of the Korean Wood Science and Technology / v.43, no.1, 2015 , pp. 25-35 More about this Journal
Abstract
The goal of this study was to review the visual grading and allowable stress determination methodologies for the domestic softwood. Previous studies used different grading (KFRI 1995-27, KFRI 2000-39, KFRI 2007-3, KFRI 2009-1) and allowable stress determination methodologies (ASTM D 245, KS F 2152, JAS 1990). The results of the visual grading were different by each researcher. Compared to the $1^{st}$ grade proportion from the previous studies using the previous specification on visual grading (KFRI 1995-2007), a higher $1^{st}$ grade proportion was found from the studies using the current specification (KFRI 2009). Compared to the allowable stress values from the small clear sample, the higher allowable stress values from the structural size were found. The results indicated that the strength reduction factor used in small clear sample was too conservative for the different grades. To obtain consistent results for the grade, it is required to have experts in visual grading and authorized organizations. An official standard methodology for the allowable stress value determination needs to be defined for the reliable stress value.
Keywords
domestic softwood; visual grading rules; allowable stress; adjustment factor; strength ratio;
Citations & Related Records
Times Cited By KSCI : 5  (Citation Analysis)
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