Study on the Photoelastic Stress Determination of Plate Beams having Circular Arc Projections

Abstract

The specimens of plate beams having a circular arc projection on one side or on either side symmetrically were prepared by an epoxy plate and the stress distribution under an uniform bending moment or the tensile load was studied by photo-elastic experiment. The results are as follows : The maximum stress always occurs near the root of the projection and the stress concentration factor at the maximum stress position in the plate beam having an arc projection on one side is larger than that having an arc projection on either side symmetrically, and then the factor under the tensile load is larger than that under the uniform bending moment. The factor α is affected by the height ΔH and the length θ of the arc projection, the radiue of curvature r at the root of the projection and the original breadth H of the plate beam. The smaller r/H, θ or the larger ΔH/H is, the larger α is obtained, and α increases suddenly when r/H is smaller than about 0.1.