Effective stress criterion for rubber multiaxial fatigue under both proportional and non-proportional loadings

Abstract

Durability of rubber antivibration products is an essential requirement for engineering design and applications. The most challenging issue is the effective assessment on the fatigue damage of the products in a design process within a required time frame. The critical plane search method can detect a failed plane at the expense of CPU time and storage. In this study, an effective stress tensor was utilised in multi-axial stress states. This criterion was fully implemented to a non-proportional case for the first time. The presented two cases, a Spherilastic bearing for industrial antivibrations under proportional loading and an AE2 specimen for fatigue tests under non-proportional loading, demonstrated that the effective stress reached its maximum at critical locations where fatigue cracks were observed in experiments. Less than 1% CPU time, compared with the critical plane search method, would only be needed for an analysis on a fatigue case of a three-dimensional solid using the proposed approach. Therefore, the approach could save a great deal of time, significantly expediting the design process. The features of the proposed approach, i.e. visibility of both critical locations and effective stress ranges for an entire component, would also help design engineers to achieve their targets within a reasonable time frame.