PROGRESS OF WOOD DECAY AND VERIFICATION OF PREDICTION MODEL UNDER ISOTHERMAL CONDITIONS

Abstract

This study focuses on clarification of wood decay process and verification of a prediction model under isothermal conditions. After moisture properties of decayed wood were investigated, wood decay tests considering moisture balance were implemented with the following conditions; one is stable test with multi-layer wood samples under constant relative humidity; the other is dynamic test with single-layer wood samples under variable relative humidity. Progress of the wood decay for the internal direction was demonstrated in the stable test, and impacts of grain on the moisture distribution of the multi-layer wood samples were observed. The results of the dynamic test indicated that wood decay process was temporarily suspended during hygroscopic conditions. The calculation results by the prediction model could simulate aforementioned phenomena related to both mass loss and moisture content of the wood samples. Additionally, accuracy of the prediction model was discussed in comparison to the results of the decay tests.