Effect of material nonlinearity on the toughness evaluation in quasi-static mode II interlaminar fracture toughness tests of composite laminates

In mode II interlaminar fracture toughness tests of composite laminates, the fracture toughness evaluated based on linear elastic fracture mechanics deviates from the true toughness due to the material nonlinearity of the matrix. In this study, an elastoplastic finite-element analysis was performed on a new quasi-static mode II interlaminar fracture toughness test, i.e., the doubly end-notched tension (DENT) test, to investigate the difference...