Measurement of Principal Residual Stresses in Orthotropic Plate : Principal Residual Stresses in Wooden Plate

Abstract

For measurement of two principal residual stresses existing in an isotropic plate such as metallic one, Treuting-Read's or Kuno-Doi's Method by deflection, and Doi's Method by strain gauge have been proposed. But they are not applicable to an orthotropic plate because of their large errors. The authors proposed in this paper the measurements of two principal residual stresses in an orthotropic plate when their directions were known. The experimental technique is as follows : thin layers are successively removed from one surface of the plate and the resulting change of curvature (Curvature Method) or strain (Strain Method) of the remaining plate is measured at any time, then their stresses are calculated. The authors'methods treat the measurements of an isotropic plate as a special case of elastic compliances. Finally, the authors showed two principal residual stresses in a wooden plate.