Measuring Non-Uniform Residual Stress in Thin Plates by a Proposed Hole-Drilling Strain Gauge Method

In this paper, a new proposed through hole-drilling strain gauge method is developed to determine the magnitudes and directions of the principal residual stresses, and the stress gradients in the directions of the principal residual stresses of the in-plane non-uniform biaxial residual stresses in thin plates. The variation of the residual stresses in the directions of the principal residual stresses at the region close to the measured point can be predicted simultaneously with the calculated gradients. Two thin butt-welded specimens were prepared in this study to verify the accuracy of the proposed method in comparison with the Kabiri’s method by using two different gauge layouts of rosettes. The experimental results show that the percentage of the relative errors between the proposed method and the Kabiri’s method are all within 9.4%. Thus, the proposed method shows good accuracy in the determination of the in-plane non-uniform biaxial residual stresses in thin plates.