A coupled plasticity correction approach to estimating notch root strains under multiaxial cyclic loading

• A new method is proposed to calculate notch-root strain under multiaxial loading.
• Relationship between pseudo field and material field of plastic moduli is proposed.
• The plastic parts of the pseudo strain increments can be directly corrected.
• Plasticity model is only used once in the proposed plasticity-correction method.
• The proposed method can obtain notch-root stress and strain at the same time.

Based on pseudo strain approach, a coupled plasticity correction approach is proposed to calculate conveniently local strains for blunt notches under multiaxial cyclic loading. A detailed algorithm of the method is presented. Compared with conventional pseudo strain based approach, the proposed method does not require the plasticity model twice. The applicability of the method was evaluated by the measured notch root strains for a notched round shaft subjected to combined axial–torsion multiaxial cyclic loading. The results showed that the proposed method was acceptable and the calculated axial strain range was more accurate than the calculated shear strain range.