An Attempt to Reduce Collapse Through Introducing Cell-Wall Deformations
Keywords:
Cell-wall deformations, slip planes, collapse, internal checking, eucalyptsAbstract
The possibility of reducing collapse through the inducement of cell-wall deformations in the wood of 1939 regrowth Eucalyptus regnans F. Muell. prior to drying was investigated. Four groups of end-matched specimens from eleven logs were used. One group served as the control and the other three were subjected to predetermined loads in compression parallel-to-the-grain.
Cell-wall deformations (physical dislocation of the cell wall as a result of longitudinal compression) were induced in all treated groups, and the number of deformations was positively correlated with the compression load. However, the compression treatment had no significant effect on recoverable collapse, the total number of internal checks, nor the total area of checking before reconditioning. Physical alterations to cell walls, therefore, did not appear to have improved the way the wood dried. Additional results suggested that internal checks may be initiated by collapse in the early stages of drying, and that their later enlargement could be attributed to drying stresses.
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