Simulations of solid lumber strength property monitoring tests

Abstract

Dimension lumber, visually graded in accordance with the National Grading Rule and assigned design values derived in accordance with procedures found in ASTM D 1990, has provided satisfactory performance in homes and other structural applications for many years. This ongoing satisfactory performance depends upon a recognition that all standards are living documents that must change over time as new information becomes available. In fact, since its original approval in 1991, D 1990 has been revised to reflect knowledge gained and the changing needs of the wood products industry. These revisions include refinements to the Grade Quality Index provisions, adoption of guiding principles for the maintenance of design values, a framework for monitoring design values, and adoption of a method for deciding when a reassessment of design values is needed. In 2014, a revision to D 1990 was adopted that focused on standardizing the minimum requirements for monitoring, evaluating, and reassessing lumber properties developed in accordance with D 1990. This paper describes the simulation methods that were used to identify a statistical test that performs acceptably (as determined by the ASTM consensus ballot process) when applied to test data from a monitoring program to determine whether a re-evaluation of the current resource is needed.

Citation

Verrill, Steve; Kretschmann, David E.; Evans, James W. 2017. Simulations of solid lumber strength property monitoring tests. FPL-RP-684. Madison, WI: U.S. Department of Agriculture, Forest Service, Forest Products Laboratory. 32 p.