Experimental Results of Green Wood Slice Under Natural Drying

Abstract

The natural or artificial shrinkage due to drying is commonly responsible of crack appears in wood pieces. These defects are even more marked on the logs pieces cut up and stored in the open air during a long time. In this fact, it is essential to understand the different processes that lead to these phenomena in the green woods. In this work, the radial and tangential strains due to the natural drying of a green wood slice are studied by analytical and experimental methods. The analytical method applied is based on a mathematical model coming from cylindrical strain calculations integrating the orthotropy and mechano-sorptive effects. The experimental device is based on the mark tracking method composed of an acquisition system recording the displacement of target posted on the wood slice during the drying process. The sample weight is measured with an electronic balance during test. As results, the moisture content evolution during drying tests and the determination of the fibre point saturation are obtained. Also according to the used analytical method, the radial and tangential strain components are posted versus the distance to the center of slide. Finally, the crack initiation region is indentified.