Engineered Properties and Structures

FS-FPL-4714

Effects of Decay on Strength of Wood

Project Objective:
Development of a basic understanding of how, why, and to what extent decay affects the mechanical properties of lumber, timber, poles and glulam and how that relates to durability. Develop predictive models to assess residual serviceability of wood in-service.

Tangible Benefits:
To develop a data base and understanding of principles from which practical guidance can be given to the engineering community and to standards organizations for a rational basis for developing residual serviceability models for wood in-service.

Results:
A new decay test method has been developed and will be reported at the next IRG/WP meeting in May 2000. Findings to date are that changes in Strength are a much more sensitive indicator of early decay than is weight loss (the current independent variable). This method may be presented to ASTM as a new test methodology for assessing decay in the near future.

Phase I:
Determination of a standard method to simulate initiation of wood decay in the natural environment (to top right).

Phase II:
Research on identifying and quantifying the relationship between changes in chemical composition and mechanical properties.

Users:
Wood Engineers, Wood Treaters, Researchers

Funding:
Federal funding, IWP&D Consortium support