The influence of shear loading on damage development in Gurson-based modelshas long been neglected resulting in inadequate fracture strain predictionsat low triaxiality where shear effects become significant. The plastic limit-load fracture criterion used in advanced Gurson models neglects the influenceof shear loading and overestimates the fracture strain and porosity at lowtriaxiality. In this paper, we extend the recently proposed shear damage model ofXue [1] to provide a stronger physical foundation by removing the simplifyingassumptions. Then we directly modify the plastic limit-load fracture criterionby coupling with the extended shear damage model to account for shearweakening and failure of the intervoid ligament in void coalescence. We applythe modified plastic limit-load criterion to predict the necking of sheet tensilespecimens and find very good agreement with the available experimental results.
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