An Energy Balance Based Approach to the End-Notched Flexure Test

Abstract

A novel approach is introduced for calculating the Mode II fracture tough ness, G _IIC , determined by the end-notched flexure test. The simple approach is based on an energy balance over the crack surface and therefore inherently takes into account shear deformation and nonlinearities during the test. The G _IIC values from the energy balance calculation are compared to those from beam theory, shear deformation beam theory, a method based on the stress intensity factor, and shear deformation plate theory. The results show that the energy balance approach is the most general and consistent in its treatment of the effect of shear deformation on G _IIC . Limitations of the other methods of calculation are also discussed.