Banner for LabNotes
From Lab Notes
Contact Information
Forest Products Laboratory
One Gifford Pinchot Drive
Madison, WI 53726-2398
Phone: (608) 231-9200
Fax: (608) 231-9592


You are here: FPL Home  / Information Products & Services  / Publications

Requested Product

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

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

Author(s)Wang, Xiping; Simpson, William T.

Publication Year: 2005  View PDF »

Category: Journal Articles

Abstract: 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

File size: 93 kb(s)

This publication is also viewable on Treesearch:  view
RITS Product ID: 12211
Current FPL Scientist associated with this product
Wang, Xiping
Research Forest Products Technologist

Additional items that might interest you
View the video celebrating FPL's 100 years of public service in 2010, from the producers of the Greatest Good....view

Research Highlights from FPL....view

Termite Eradication: A search for the Holy Grail.... view

Moisture Management in Residential Construction Series videos...view

Wood Floor Systems in Residential Construction Series videos....view
- FPL's Mission and Strategic Plan -

FPL's mission is to identify and conduct innovative wood and fiber utilization research that contributes to conservation and productivity of the forest resource, thereby sustaining forests, the economy, and quality of life. ... ..more »

- FPL Research Emphasis Areas -
Advanced Composites

As an integral part of the FPL mission, we improve the long-term sustainability of our Nation's forests by creating valuable composite products from biobased materials ... ..more »

Advanced Structures

The FPL has been in the forefront of wood-frame housing research since 1910 and has long been recognized as a world leader in such housing-related areas as engineered wood ... ..more »

Forest Biorefinery

We all know the compelling reasons that the United States needs to reduce its dependence on fossil fuels. Historically, the greatest increases in energy demand have been for transportation fuels ... ..more »


A leader in wood products research for over a century, the FPL is positioning itself to become the lead Federal research facility for the application of nanotechnology in forest products ... more »

Woody Biomass Utilization

Forests in the United States contain a substantial amount of small-diameter, overstocked, and underutilized material.FPL research projects are exploring the potential of the small-diameter ... ..more »