Maintenance Procedures for North American Visually-graded Dimension Lumber Design Values

Abstract

ASTM International D1990 Standard Practice for Establishing Allowable Properties for Visually-Graded Dimension Lumber from In-Grade Tests of Full-Size Specimens, that governs the development of design values for dimension lumber in North America, was first adopted in 1991with recognition that the resource and manufacturing of lumber could change over time impacting design values. D1990 Section 13 instructed users of the standard to conduct a reassessment of property values derived by the practice if there is cause to believe that there has been a significant change in the raw material resource or product mix but no guidance was given for how to monitor or evaluate properties to determine if a reassessment of the design values developed according to D1990 is necessary. In 2014, guidance on design value maintenance has been included in D1990. This paper presents the multiple stage design value maintenance provisions and the thought process behind developing these provisions for monitoring, evaluation, and reassessment in D1990.

Citation

Kretschmann, David; DeVisser, Don; Cheung, Kevin; Browder, Bob; Rozek, Al. 2014. Maintenance Procedures for North American Visually-graded Dimension Lumber Design Values. In: World Conference on Timber Engineering, Quebec City, Canada, August 10-14, 2014; p. 8.