Effect of Presteaming On Drying Stresses of Red Oak Using A Coating and Bending Method

Authors

  • Zuoxin Wang
  • Elvin T. Choong
  • Vijaya K. Gopu

Keywords:

Coating and bending method, drying deflection, drying stress, modulus of elasticity, presteaming, slicing method

Abstract

This study was initiated to investigate the effect of presteaming on drying stresses of red oak (Quercus sp.) using the coating and bending method. Besides the presteaming effect, a directional effect on drying stresses was also tested. Four blocks were randomly selected. Each block was divided into two pairs (four samples). One pair was randomly assigned to steaming while the other was assigned to control. A statistical split-plot model was used to analyze the results. Presteaming increased drying stress by up to 36% and decreased drying time by 23% when red oak was dried at 75% relative humidity and 44 C from average moisture content of 80 to 16%. The maximum drying stress of the steamed samples occurred before that of the unsteamed samples due to faster moisture loss from the sample. This study indicated that the coating and bending method could be used to study drying stresses of red oak. The statistical model revealed the differences between steaming and control and between inner and outer directions. Drying stresses were different in two opposite directions (outward and inward), regardless of whether the wood was steamed or not.

References

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Published

2007-06-25

Issue

Number 4 / October 1994

Section

Research Contributions

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