Effect of Moisture Content on Strength of CCA-Treated Lumber

Authors

  • Jerrold E. Winandy

Keywords:

CCA, preservative, treatment, mechanical properties, moisture content, duration-of-load

Abstract

Recent studies on the effects of chromated copper arsenate (CCA) treatment on lumber design properties have primarily evaluated the effects of such treatment at or near 12% moisture content and at failure times of 1 to 10 min. The influence of various moisture contents and faster loading rates is unknown. This report discusses the influence of moisture content and its interaction with time-to-failure on the bending strength of CCA-treated (0.4 1b/ft3 (6.4 kg/m3)) lumber. The factors studied were moisture contents of 10, 15, and ≥ 23% (green lumber) and ramp-load failure times in bending of 3-6, 30-60, and 300-600 seconds. This research concluded that a revised wet-use service factor for No. 1 and better waterborne-preservative-treated lumber is needed.

References

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Published

2007-06-19

Issue

Number 2 / April 1995

Section

Research Contributions

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