Modelling of stress softening in filled elastomers

The phenomenon of stress softening in filled elastomers, commonly known as the Mullins effect, has received renewed attention in the engineering community due to its importance in predicting the nonlinear response of elastomeric components. The stress softening is assumed to be the result of irreversible damage in the material. Ogden & Roxburgh (1999a,b) have recently developed a pseudo-elastic model to capture Mullins effect, treating it as a quasi-static phenomenon. This model, with some modifications, has been implemented in the commercial finite element software ABAQUS. This paper describes the modified Ogden-Roxburgh model, and motivates the needs for the modifications. The modified model is then used to calibrate available experimental data for several benchmark cases involving simple stress states. The model is also used for the simulation of quasi-static deformation and steady state rolling experiments on a solid rubber wheel, and the numerical results are compared with experimental data.