Initial strain energy-based thermo-elastoviscoplastic two-parameter damage self-healing model for bituminous composites—Part II: Computational aspects

This paper describes the implementation of the initial strain energy-based thermo-elastoviscoplastic two-parameter damage self-healing models for bituminous materials to compare the model predictions with experimental measurements. Computational algorithms based on the two-step operator splitting methodology are proposed and employed for numerical results. The elastic two-parameter damage self-healing predictor and the viscoplastic corrector are coupled with the Arrhenius-type temperature term via the net stress concept in conjunction with the hypothesis of strain equivalence and then systematically used for numerical implementation of the models. Four numerical examples of three-dimensional problems are first demonstrated for the effect of temperature and rest period for healing phenomenon. Second, experimental validation of the proposed model against monotonic constant-strain test at different temperatures and controlled-strain cyclic tension test is presented. It is observed that numerical simulations by the two-parameter model agree well with experimental results. In particular, the softening responses of the bituminous composites are well predicted for monotonic constant-strain rate test and the viscous damage behavior can be reasonably predicted by the proposed two-parameter damage models. It is noted that the two-parameter model can better predict the thermo-mechanical behavior of asphalt and is more versatile than the one-parameter isotropic damage self-healing model.