Relief Holes for Stress Mitigation in Infinite Thin Plates With Single Circular Hole Loaded Axially

Abstract

The stress concentration factor in an infinite thin plate with single circular hole, loaded axially is approximately 3. The reason of this high stress is explained through stress flow lines, similar to stream lines in a ideal fluid flow around a circular obstacle. Various methods for stress mitigation have been reported in literature. In the case considered it can also be reduced by removing material from the vicinity. In the present work the removal of the material, introduction of two smaller relief holes, is proposed in such a way that the stress flow lines will follow an elliptical path and thus reducing the stress concentration effect. The size of the relief holes and center distance between the holes are formulated for minimizing the stress concentration effect. The problem is analyzed using FEA software ANSYS. The result is encouraging in a way that for a particular circular singularity the size of the relief hole and center distance is formulated for minimizing the stress concentration factor.