A quantitative assessment of exponential damage law parameters and their effects on macro-damage initiation and evolution in gradient-enhanced continuum damage model

Gradient-enhanced continuum damage model has been implemented in various structural damage and failure modeling problems with a great degree of effectiveness, ease and accuracy. In computational framework, damage evolution in the material depends very much on the choice of damage evolution laws. The parameters involved in the damage evolution laws impart sensitivity in depicting the numerical response of the modeled damage and failure of the structure. Present work focusses on addressing these aspects in implementation of exponential damage evolution laws by performing a detailed quantitative assessment to investigate the relative effects of damage law parameters: gradient parameter, strength ratio and damage softening parameters on macro-damage initiation and evolution in mode-I failure. The gradient-enhanced continuum damage model is implemented via ABAQUS user element subroutine (UEL) with nonlinear finite element formulation. Also, present work interprets the relative effects of damage law parameters on the numerical solution and provides detailed insights on their implications on damage modeling and analysis.