COMPARISON OF NONDESTRUCTIVE TESTING METHODS FOR EVALUATING NO. 2 SOUTHERN PINE LUMBER: PART A, MODULUS OF ELASTICITY
Modulus of elasticity (MOE, or E) is one of the main quality indicators in structural lumber stress grading systems. Due to a relatively high amount of variability in contemporary sawn lumber, it is important that nondestructive evaluation technology be utilized to better discern high-E-value pieces from low-E-value pieces. The research described in this study is from a laboratory test of three nondestructive technologies applied to 343 pieces of visually graded No. 2 southern pine lumber collected across the southeast region of the United States. The evaluated technologies included continuous lumber test in continuous proof bending (Metriguard Model 7200 High Capacity Lumber Tester), transverse vibration (Metriguard E-Computer), and two stress wave tools (Falcon A-Grader and Carter Holt Harvey Director HM200). For each of the nondestructive techniques, results were compared with static E as determined by the four-point static bending tests following ASTM D198-14. In all cases, the nondestructive techniques successfully predicted E for all lumber sizes, with linear regression r2 values ranging from 0.77 to 0.86.
The copyright of an article published in Wood and Fiber Science is transferred to the Society of Wood Science and Technology (for U. S. Government employees: to the extent transferable), effective if and when the article is accepted for publication. This transfer grants the Society of Wood Science and Technology permission to republish all or any part of the article in any form, e.g., reprints for sale, microfiche, proceedings, etc. However, the authors reserve the following as set forth in the Copyright Law:
1. All proprietary rights other than copyright, such as patent rights.
2. The right to grant or refuse permission to third parties to republish all or part of the article or translations thereof. In the case of whole articles, such third parties must obtain Society of Wood Science and Technology written permission as well. However, the Society may grant rights with respect to Journal issues as a whole.
3. The right to use all or part of this article in future works of their own, such as lectures, press releases, reviews, text books, or reprint books.