Surfacing, steaming and freezing are widely used pretreatment methods to improve the drying rate and to reduce drying defects of wood. In this study, Douglas fir (Pseudotsuga menziesii) wood samples were treated with steaming or freezing, and the resulting drying behaviors such as drying rate, drying strain and drying defects were investigated and compared with those of control wood using an optical measurement system and a digital image correlation DIC method. In the case of steaming pretreatment, the observed drying rate was faster and drying strain was milder than control wood. However, there were almost no differences between control and pre-frozen wood regarding the drying behaviors. Tangential strain (e2) of steam-treated wood was larger than that of control and freeze-treated wood. Moreover, the effect of pretreatment was not uniform over the entire wood specimen. The drying check position could be approximately predicted by the analyzing of the strain ratio (μ) and strain velocity (v) graphs during the final drying period.
|Number of pages
|Journal of the Faculty of Agriculture, Kyushu University
|Published - Feb 2014
All Science Journal Classification (ASJC) codes
- Agronomy and Crop Science