ENERGY DENSITY APPROACH TO CALCULATION OF INELASTIC STRAIN STRESS NEAR NOTCHES AND CRACKS

An energy-based method of calculating elastic-plastic strains and stresses near notches and cracks is presented. It was assumed that the strain energy density in the plastic zone ahead of a notch can be calculated on the basis of the elastic stress-strain solution. Good agreement between the calculated and measured notch strains was obtained for several notches, materials and loading conditions. It was shown that the assumption holds up to general plastic yielding. This method can also be applied in uniaxial and multiaxial stress states. A numerical procedure suitable for any material stress-strain curve is presented. Some possibilities concerning elastic-plastic stress-strain calculation near cracks are also discussed.