Allowable bending stresses of wood for use in portable wood ladders

Fred Werren

Treesearch

Allowable bending stresses of wood for use in portable wood ladders

Informally Refereed

Authors:

Fred Werren

Year:

1975

Type:

General Technical Report

Station:

Forest Products Laboratory

Source:

Gen. Tech. Rep. FPL-05. Madison, WI: U.S. Department of Agriculture, Forest Service, Forest Products Laboratory. 6 p.

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Download (PDF 46 KB): https://research.fs.usda.gov/download/treesearch/9824.pdf

Abstract

A standard for portable wood ladders has been in effect since 1923, and has been revised several times since then. The most recent publication is "American National Standard Safety Standard for Portable Wood Ladders," A14.1-1975, from American National Standards Institute, Inc. Methods of arriving at allowable stresses for wood ladder parts have never been clearly documented. This report out lines what was done in the latest revision of the standard to calculate allowable fiber stresses for establishing species groupings.

Keywords

Safety, ladders, strength, bending stress, grading, knots, strength of wood, bending

Citation

Werren, Fred. 1975. Allowable bending stresses of wood for use in portable wood ladders. Gen. Tech. Rep. FPL-05. Madison, WI: U.S. Department of Agriculture, Forest Service, Forest Products Laboratory. 6 p.