Ceramics-Silikáty 52 (3) 160-164 (2008)

STRESS PROFILE MEASUREMENT IN AXIALLY SYMMETRIC GLASS SAMPLE

N. Krečmer , M. Liška , J. Chocholoušek , P. Vrábel

The method based on the Senarmont compensation was proposed enabling the determination of the radial distributions of the axial, tangential and radial stress components in the cylindrical glass sample. The phase difference dependence on the radial coordinate was measured for light propagation through the sample in the axial and perpendicular (with respect to the axis of symmetry) direction. The numerical analysis based on the Taylor expansion of the radial distribution of particular stress components was used in combination with the linear regression analysis for evaluation of the stress components radial profiles and their confidence limits. Statistical treatment of experimental data obtained proved that when the cylindrical symmetry of the stress distribution is retained the Taylor expansion up to quadratic terms is sufficient for the description of stress distribution. The 95% confidence intervals of the obtained stress distributions are sufficiently narrow, corresponding to the relative error of the particular stress components values on the level of 5-10%.

Keywords: Stress measurement, Senarmont method, regression analysis