A unified and accurate approach to simulating monotonic and cyclic failure effects of metallic and concrete materials

Purpose A unified and accurate approach is established for the purpose of simulating monotonic and cyclic failure effects of metallic and concrete materials based on an all-through strength-degrading elastoplasticity model. This new model makes no reference to any usually postulated yield conditions and can characterize non-symmetric tensile and compressive responses. Moreover, both low and high cycle fatigue effects can be effectively treated without involving very high time consumption in carrying out a great number of numerical iterative procedures. Design/methodology/approach The continuity in tangential elastoplastic moduli is guaranteed by a new flow rule in unified and smooth form. As such, plastic strain rate is induced throughout every stage of each loading and unloading process, thus leading to all-through dissipated effects. The tension-compression asymmetry is in a unified manner characterized by means of a stress mode invariant. Both hardening and softening effects are represented by introducing tensile and compressive strength functions in unified and explicit forms. A unified critical criterion for both monotonic and cyclic failure is derived with direct algorithms for calculating cumulative dissipation. Numerical examples for model validation are presented and compared with multiple data sets for metallic and concrete samples. Findings It is found that both monotonic and cyclic failure effects can be directly simulated in a unified manner with gradual degradation in elastoplastic strength. Originality/value Complexities involved in usual approaches to simulating either distributive micro-cracks or developing macro-cracks are bypassed with the new model. High-efficiency schemes ensure predictive capabilities with high accuracy.