Determination of K_I, K_(II) and trajectory of initial crack by adaptive finite element method and photoelastic technique

摘要

The stress intensity factors K_I and K_(II), including the trajectory of the initial crack, are determined using the adaptive finite element method and the photoelastic technique. Crack propagation in two-dimensional fracture mechanics problems is normally caused by mixed mode loading. The reflection photoelastic technique can be used to determine the state of stresses and crack speed on transparent material under both the static and dynamic conditions. The adaptive finite element method and the photoelastic technique are evaluated by using the three benchmark problems including the single-edge cracked plate, the double-edge cracked plate, and the slant-edge cracked plate, all under uniaxial tensile loading. The results obtained from the finite element method and the reflection photoelastic techniques are compared by using the stress intensity factors. The differences of the stress intensity factor K_I obtained from the finite element method and the photoelastic technique are 0.88 and 3.12%, respectively for the single-edge cracked plate.