Some Stress-Grading Criteria and Methods of Grade Selection for Dimension Lumber.
Abstract
The paper demonstrates procedures for selecting machine grades of lumber based on experimental evidence of what can be produced, along with knowledge of required performance in use. It shows as an example that, for 2 by 8 southern pine floor joists, E-grades with a 1/3 edge-knot limitation are nearly ideal if the joists are used on a 24-inch spacing, or with a 1/2 edge-knot limitation if used on a 12-inch spacing. Relations of bending strength, tensile strength, and compressive strength to full-span modulus of elasticity and strength ratio are given. The methods described can be used for any species. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Dec 01, 1970
- Accession Number
- AD0715991
Entities
People
- R. L. Ethington
Organizations
- Forest Products Laboratory