Hybrid Stress Analysis around a Circular Hole in a Tensile Plate by Use of Phase Shifting Photoelasticity

A hybrid experimental-numerical method is presented for determining the stresses around a circular hole in a finite-width, tensile loaded plate. Measured fringe orders along straight lines provided the input information on the external boundary of the hybrid element. In order to see the effects of varying stress field, different numbers of terms in a power-series representation of the complex type conformal mapping stress function were tested. For qualitative comparison, actual isochromatic fringes were compared with reconstructed theoretical fringes using stress-optic law. For quantitative comparison, relative errors and standard deviations with respective to relative errors were analyzed for all measured points by changing the number of terms of stress function. The hybrid results are highly comparable with those predicted by FEA. The results show that this approach is effective and promising because isochromatic data along the straight lines in photoelasticity can be conveniently measured by use of phase shifting photoelasticity