Higher order terms of the crack tip asymptotic field for a wedge-splitting specimen

The coefficients of the crack tip asymptotic field of a typical wedge-splitting specimen are computed using a hybrid crack element (HCE), which has the potential to directly calculate not only the stress intensity factor (SIF) but also the coefficients of the higher order terms of the crack tip asymptotic field. The approximate closed-form expression for SIF proposed by Guinea et al. (1996) is calibrated by the results of the HCE. Approximate expressions for the second and third order terms for the wedge-splitting specimen are obtained by fitting the computed data. Numerical results show that the coefficients for terms higher than three are negligibly small, thus the wedge-splitting specimen is more stable than other geometries.