적송재(赤松材)의 흡습(吸濕)과 팽창성(膨脹性)에 관(關)하여

The hygroscopic and swelling properties of Korean Red Pine wood

Many kind tree species are growing in Korea. However most of them are inferior in wood qualities and production for commercial utilization except several species. Among the useful several species Red Pine (Pinus densiflora S. et. Z.) is growing in main tree species and most generally utilizing wood in korean forest. It is used widely as mine timbers, cross ties, boxes, floorings, pulpwoods, constructions and engineerings. Although this species is most useful and economical in this country, the basical properties on relation between wood and relative humidities were not studied certainly. This study was performed by need of inspection the hygroscopic and swelling properties to be apllied for physical manufacturing. According to the results the Equilibrium Moisture Contents of each relative humidity conditions are as table (3), and the swelling values of sap and heartwood are as table (4) and (5) in text. In this study sapwood moisture contents are higher than heartwood in each relative humidities conditions. Tangential and radial ratios of average swelling values are 1:1.971 in sapwood and 1:2.178 in heartwood.