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 Research Station
Help
 

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

View PDF (14 KB)

Title: Ultrasonic propagation properties of red oak

Author: Yuhas, Donald E.; Isaacson, Bruce G.; Schmoldt, Daniel L.; Wengert, Eugene;

Date: 1999

Source: Proceedings, 11th International Symposium on Nondestructive Testing of Wood

Publication Series: Miscellaneous Publication

Description: This work was motivated by the need to identify ultrasonic parameters that exhibit the greatest sensitivity to wood degradation as the result of bacterial infection; the so-called ?wetwood? condition. Wetwood infection creates microscopic changes to the wood structure, which then surface as checks and shake following drying. Slower drying schedules can often mitigate the appearance of these drying flaws, however, so there is value in being able to identify problem boards prior to the drying stage. In order to generate baseline ultrasonic property data on red oak, a series of drying experiments was conducted to develop populations of ?normal? and ?bacterial damaged? wood. For these studies, a total of 30 red oak samples was taken from boards harvested from two different U.S. geographical regions (Wisconsin and Virginia). We describe the ultrasonic analysis of red oak over the frequency range from 100 to 500 kHz. Although numerous ultrasonic studies have been conducted using p-waves (longitudinal), very few experiments have been reported that combine both p-wave and s-wave (shear) measurements. To separate the different ultrasonic modes, all ultrasonic data was acquired using highly damped transducers. By making repeat measurements at several stages during the drying cycle, we were able to quantify the relationships among various ultrasonic parameters and other wood properties such as moisture content, wood macrostructure, geographical origin, and bacterial damage. Our measurement matrix included ultrasonic velocities, attenuation, and frequency dependent attenuation for all ultrasonic modes. While none of the velocity modes showed any sensitivity to bacterial damage, several attenuation modes exhibited a substantial increase that was attributed to bacterial damage. This presentation described the test methods, showed data for all ultrasonic modes, and discussed the potential for using attenuation as a nondestructive method to determine the extent of bacterial infection in oak.

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.
  • You may send email to pubrequest@fs.fed.us to request a hard copy of this publication. (Please specify exactly which publication you are requesting and your mailing address.)

XML: View XML

Citation:


Yuhas, Donald E.; Isaacson, Bruce G.; Schmoldt, Daniel L.; Wengert, Eugene 1999. Ultrasonic propagation properties of red oak. Proceedings, 11th International Symposium on Nondestructive Testing of Wood

 


 [ 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.