Time-dependent behaviour of T300/5208 under creep, relaxation and ramp loading

An investigation of the effect of time-dependent behaviour for various stress and strain histories was done for the T300/5208 composite. It is shown that Schapery”s non-linear theory integrated with a viscoplastic model allows to predict for long-term cyclic mechanical loading, ramp loading with constant strain rate and multiple-step relaxation. Material constants associated with constitutive models were determined. The results were combined with a recursive numerical procedure to handle the hereditary effects and to predict the time-dependent behaviour of the composite.