LAUSR

Abstract Multiple cracks are frequently detected in structural components and should be assessed aimed to judge whether they can be treated as individual cracks or be combined to a larger crack. To study the ductile failure and crack interaction behavior, tensile tests using flat plates with two through-wall cracks were conducted, and 3D digital image correlation method (3D-DIC) was applied to acquire the displacement and full-field strain measurement. A damage evolution model integrated with a non-monotonic fracture strain locus was implemented to model the ductile fracture and crack interaction. Simulation results including load-displacement curves and predicted crack coalescence results fit well to the experiment data. Effects of mesh size and cut-off value of stress on the simulation results were investigated to ensure the accuracy of finite element analysis. The findings show that FE predictions using non-monotonic fracture strain locus are not only superior to those using monotonic ones, but also more accurate than alignment and combination rules in fitness-for-service codes.