Strain-Based Fatigue Criterion for Rubber Damage Under Uniaxial Loadings

In the present work, the fatigue life of styrene-butadiene rubber is investigated by means of an engineering approach consisting in testing two different specimen geometries: axisymmetric sample AE2 and diablo sample AE42. Samples are subjected to a 5 Hz sinus waveform cycle for a variety of displacement maxima and a load ratio of zero. The first specimen AE2 is used to calibrate the predictive model and the second one AE42 is used to validate the suggested model. Predictive models based on various damage parameters, which are essentially the different deformation types are examined on the first geometry (AE2). All the deformation parameters investigated provided very accurate estimations of fatigue life. In fact, the experimental results show an R2 correlation coefficient exceeding 0.9. Then, the second AE42 geometry is used to validate the predictive models established for the AE2 geometry. To this end, a non-linear finite element analysis model was carried out. The damage parameters are calculated through ABAQUS and then introduced into the already developed predictive models. The numerical results obtained are in good agreement with the experimental results. It was found that the prediction models developed for the first geometry are well adapted to fatigue life prediction of the second geometry, with an impressive degree of agreement between predicted and experimental results.