Numerical analysis of cracked inelastic shells with large displacements or mixed mode loading

The trend in higher utilization of structural materials leads to a need for accurate numerical tools for reliable predictions of structural response[ In some instances both material and geometrical nonlinearities are allowed for\ typically in assessments of structural collapse or residual strength in damaged conditions[ Dynamically loaded structures are prone to fatigue cracking^ this has to be accounted for when computing nonlinear structural response[ The present study addresses the performance of cracked inelastic shells with out!of!plane displacement not negligible compared to shell thickness[ This situation leads to membrane force e}ects in the shell[ Hence\ a cracked part of the shell will be subjected to a nonproportional history of bending moment and membrane force\ and e[g[ fracture mechanics parameters "J!integral# are a}ected[ A Mindlin shell _nite element based nonlinear program is developed and utilized herein[ The cracked parts are accounted for by means of inelastic line spring elements[ These elements also account for possible mode II deformations