木材 乾燥過程의 動 彈性的 特性

Characteristics of Dynamic Elasticity during Wood Drying

To clarify the characteristics of the dynamic elasticity during wood drying. dynamic Young s modulus and internal friction were investigated in drying chinese cork oak (Quercus variabiis blume) and black locust (Robinia pseudo-acacia L.) (hardwoods) and black pine (Pinus thunbergii Parl) (softwood). The results are summerized as follows : 1. The dynamic Young s modulus in chinese cork oak increased with decreasing moisture content and this was more pronounced at high temperatures. 2. In black locust the dynamic Young s modulus did not change above the FSP, while it increased with decreasing moisture content belo ι the FSP. 3. There was no change in the dynamic Young ’ s modulus of black locust at high temperatures. 4. The internal friction in black pine and chinese cork oak showed little change with decreasing moisture content. The internal friction in black pine was higher than that in chinese cork oak. 5. The internal friction in black locust decreased with decreasing moisture content in low temperatures.