Fracture toughnesses of interlaminar fracture of glued-laminated timber
Critical strain energy release rate GC and stress intensity factor KC are both defined as fracture toughness, and they can be converted to one another through an equivalent elastic modulus for wood fracture. Whereas the equivalent elastic modulus for interlaminar fracture toughness of glued-laminated timber (glulam) is kept unknown. This paper briefly presented Modes I and II interlaminar fracture toughnesses of glulam, which were obtained from double cantilever beam (DCB) and three-point bending end-notched flexure (3ENF) tests using finite element method (FEM). On the basis of Hankinson-type formula and equivalent elastic modulus of wood fracture, this study developed two empirical expressions to calculate the equivalent elastic moduli for Modes I and II interlaminar fracture of glulam.