Prediction for stress relaxation history of industrial rubber with viscoelastic material model

Abstract

A viscoelastic model for stress relaxation of industrial rubber materials was developed. This model is a Kelvin–Voigt type viscoelastic model combining a single spring and a fractional differential viscoelastic model. To confirm the robustness and effectiveness of the proposed model, various stress relaxation tests of three types of SBR-CB with different volume fractions were carried out. Then, some experimental and numerical tests were carried out. As the results, the stress relaxation history was predicted by this model using the material constant identified with experimental data between from 60 to 120 sec, showing good agreement with experimental ones over 100,000 sec. Then, by using the proposed model, a long-term stress-strain relationship was predicted from the multi-step relaxation test.