Numerical Investigation of Multiaxial Fatigue Life Prediction Criteria for an SBR

The purpose of this paper is to conduct a comparative study on various fatigue criteria employed in predicting the multiaxial fatigue life of rubber materials. In order to achieve this objective, a recent energetic criterion Cracking Energy Density (CED) is presented at the outset. The parameter CED, which is derived from the strain energy density (SED), may forecast the onset of the first crack and its possible direction, according to the loading path. An analytic analysis of the CED based on Neo-Hookean model is carried out. The analytic study is limited to some typical load cases. Then, some CED properties are mentioned for typical load cases. To generalize this study, a Finite Element Analysis (FEA) is used to model the multiaxial loadings. The FE model allows calculating some basic fatigue criteria mentioned on literature such as the engineering deformation \(\varepsilon_{1,\max }\) , the elongation \(\lambda_{\max }\) , the second Pioal-Kirschoff stress \(S_{\max }\) and the CED parameter \(W_{c,\max }\) . The pertinence and the effectiveness of these fatigue criteria to more correlate the fatigue results are evaluated by means of the correlation coefficient R2. It was found that the CED parameter presents the highest correlation coefficient. So, this parameter can be considered as the most pertinent criterion to define the fatigue of rubber materials.