A speed-dependent cohesive zone model for moving cracks with non-uniform traction force

Steady-state moving crack under mode-I loading is studied with a modified cohesive zone model which addresses speed-dependent role of the normal stress parallel to the crack axis and the non-uniformity of traction force in cohesive zone. Unlike the classical Dugdale model which predicts independence of the cohesive zone size on crack speed, the present model predicts that the cohesive zone size strongly depends on crack speed. Comparison with some known experimental data suggests that the present model has the potential to capture the speed effects on moving cracks in ductile materials especially at high crack speed.