Ultrasonic Timber Grading Applied to Forest Products
J. L. Sandoz, A. Pavillet
ABSTRACT The speed of ultrasound measured with Sylvatest applied on the laminated products has been studied for a long time in the chair of timber construction IBOIS. The most completed experience gained using this device concerns the local Swiss and French spruces.
For a few years, the interest of the application of this ultrasonic method on the forest products has been taken into account. The main idea is the study of an "indirect" axial measurement on logs and living trees in order to link it to the expected mechanical values of the laminated.
The first problem for measuring logs is the high moisture content. Indeed, usually when using the Sylvatest on timbers, the moisture content can be very different and some corrections can be done according to the different values. But in the logs or in the living trees, this disturbing effect is less important. It is due to the more uniform distribution of the moisture in the wood cells of this kind of products. Most of them can be considered up to the saturation point.
Publication Source: WCTE '98 - 5th World Conference on Timber Engineering, 1998 August 17-20, Montreaux, Switzerland.
Vol. 2, Pages 818.....
Publisher: Presses polytechniques et universitaires romandes - [Homepage]
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