Estimations of the T-stress for small cracks at notches
The T-stress is increasingly being recognized as an important additional stress field characterizing parameter in the analyses of cracked bodies. Using T-stress as the constraint parameter, the framework of failure assessments including the constraint effect has been established; and the effect of T-stress on fatigue crack propagation rate has been investigated by several researchers. In this paper, a simple method for determining the T-stress for small notch-emanating cracks is presented. First, the background on the T-stress calculation using the superposition principle and the similarities between the elastic notch-tip stress fields described by two parameters: the stress concentration factor (Kt) and the notch-tip radius (ρ), are summarized. Then, the method of estimating T-stress for both short and long cracks at the notches is presented. The method is used to predict T-stress solutions for cracks emanating from an internal hole in a wide plate, and cracks emanating from an U-shaped edge notch in a finite thickness plate. The results are compared to the T-stress results in the literature, and the T-stresses solutions obtained from finite element analysis. Excellent agreements have been achieved for small cracks. The method presented here can be used for a variety of notch crack geometries and loading conditions.
|Keywords||Constraint effect, Cracks at notches, Notch radius, Stress concentration factor, T-stress|
|Journal||Engineering Fracture Mechanics|
Wang, X, Lewis, T. (Timothy), & Bell, R. (Robert). (2006). Estimations of the T-stress for small cracks at notches. Engineering Fracture Mechanics, 73(3), 366–375. doi:10.1016/j.engfracmech.2005.06.009