Computation of mode I notch stress intensity factors in a V-notched TPB specimen

Three-point bend (TPB) specimen is an important test sample in fracture study of notched components made from brittle materials like rocks and ceramics. On the other hand, the notch stress intensity factors (NSIFs) are vital parameters in brittle fracture assessment of V-notched structures. Therefore, computation of NSIFs in TPB specimens is of practical interest to engineers and researchers. Since the available methods for calculating NSIFs are often cumbersome and need complicated calculations, it is preferred to show them as a set of dimensionless parameters. In this research, by using a finite element approach called FEOD method, the stress intensity factors are determined numerically for notched TPB specimens having different geometry and loading conditions. The obtained values of NSIF are then converted to dimensionless parameters called notch shape factors YIV and are illustrated in a number of discrete figures. It is shown that each of the three parameters of: the notch opening angle, the notch length and the distance between the two supports has direct relation with YIV. The results presented in this paper can be used by designers and engineers for performing the necessary fracture experiments through the TPB specimen without needing complicated and time-consuming calculations.