Skip to page content
USDA Forest Service
  
Treesearch

Research & Development Treesearch

 
Treesearch Home
About Treesearch
Contact Us
Research & Development
Forest Products Lab
International Institute of Tropical Forestry
Northern
Pacific Northwest
Pacific Southwest
Rocky Mountain
Southern
Help
 

GeoTreesearch


Science.gov - We Participate


USA.gov  Government Made Easy


Global Forest Information Service

US Forest Service
P.O. Box 96090
Washington, D.C.
20090-6090

(202) 205-8333

You are here: Home / Search / Publication Information
Bookmark and Share

Publication Information

(93 KB bytes)

Title: Acoustic analysis of warp potential of green ponderosa pine lumber

Author: Wang, Xiping; Simpson, William T.

Date: 2005

Source: Proceedings : 9th International IUFRO Wood Drying Conference : 2005 August 21-26, Nanjing, China. Nanjing, China : Nanjing Forestry University, 2005: pages 155-160.

Publication Series: Not categorized

Description: This study evaluated the potential of acoustic analysis as presorting criteria to identify warp-prone boards before kiln drying. Dimension lumber, 38 by 89 mm (nominal 2 by 4 in.) and 2.44 m (8 ft) long, sawn from open-grown small-diameter ponderosa pine trees, was acoustically tested lengthwise at green condition. Three acoustic properties (acoustic speed, rate of wave attenuation, and acoustic modulus of elasticity (MOE)) were then determined through waveform analysis. Boards were then kiln dried, and warp was measured immediately after drying and after equilibrating to about 13 percent equilibrium moisture content. Crook and bow measured after drying decreased as acoustic speed and acoustic MOE of green boards increased and rate of wave attenuation of green boards decreased Twist was found to have no relationship with any acoustic propelties of green 2 by 4’s. The results also show a statistically significant correlation between acoustic properties of green 2 by 4’s and the grade loss caused by exceeding warp limits. As the number of Structural Light Framing grade losses from the green grade increased, the acoustic speed and acoustic MOE decreased significantly, whereas rate of wave attenuation increased significantly. However, no relationship was found between green board density and warp and grades lost.

Keywords: Wood, grading, elasticity, modulus of elasticity, ponderosa pine, drying, nondestructive testing, wood moisture, green lumber, equilibrium moisture content, warping, acoustic testing, ponderosa pine, kiln drying

Publication Notes:

  • We recommend that you also print this page and attach it to the printout of the article, to retain the full citation information.
  • This article was written and prepared by U.S. Government employees on official time, and is therefore in the public domain.

XML: View XML

Citation:


Wang, Xiping; Simpson, William T. 2005. Acoustic analysis of warp potential of green ponderosa pine lumber. Proceedings : 9th International IUFRO Wood Drying Conference : 2005 August 21-26, Nanjing, China. Nanjing, China : Nanjing Forestry University, 2005: pages 155-160.

 


 [ Get Acrobat ]  Get the latest version of the Adobe Acrobat reader or Acrobat Reader for Windows with Search and Accessibility

USDA logo which links to the department's national site. Forest Service logo which links to the agency's national site.