Abstract: 

Rubber isolators operate in a high-dynamic environment, and fatigue damage often occurs during service. Simulation of fatigue crack initiation and propagation is very challenging in engineering design. Fracture mechanics is the dominant approach to this problem, using parameters measured from pre-cut plane specimens. However, in actual 3D products under multiple axial loading conditions, it is difficult to obtain consistent results. Since Abaqus software provides user subroutines to control elements' response under external loadings, it is possible to use these facilities to assess the fatigue cracks. An Abaqus simulation was performed after a rubber spring used in a rail vehicle failed during the fatigue test. The results show that fatigue crack initiation occurred at approximately 82k cycles, compared with the predicted 81k cycles, and that after 125k cycles were completed, the observed crack length propagated to 97mm, whereas the predicted value was in the range 93–95mm. Therefore, the prediction successfully evaluated the fatigue crack initiation and propagation. The presentation will show the whole simulation procedure and the results obtained.

Presenters: 

Robert Luo Principal CAE engineer - Trelleborg Dr. Robert Luo holds BEng, MEng and PhD qualifications and the position of the Chartered Engineer, the Fellow of the Institution of Mechanical Engineers. He has 34 years’ experience in Abaqus, published 3 books and more than 70 peer-reviewed journal papers. He is a SIMULIA Champion since 2021.