Estimation Using Initial Strains

Abstract

Residual stresses in many long structural parts can be idealized as distributed uniformly in the axial direction with little out-of-plane shear stresses. Examples are rods, beams, rails, and long butt or fillet welds between two plates. In many cases the residual stresses arise under conditions which are not easily simulated by numerical computation. Figure 9.1-A shows schematically a section of rod and beam while Fig. 9.1-B shows a section of butt weld be- tween two plates. In these examples the constraint is often such that residual stress in the z-direction would be expected to be the most severe. Therefore, an essential aspect in assessing the integrity of these parts is to measure the distribution of axial (z-axis) stress.