“…In fact, multiple experimental studies indicated that the fracture energies in modes I and mode II are different, e.g. Araki et al [14], Benzeggagh and Kenane [15], Dollhofer et al [16], Pang [17], Warrior et al [18] and Yang et al [19]. Furthermore, when the interface is under a large normal compression condition, the maximum shear traction will become negative and this does not appear to be realistic [20].…”