Theoretical stress concentration factors for short flat bars with opposite U-shaped notches subjected to in-plane bending

The values of existing theoretical stress concentration factors for rectangular uniform thickness plates, with opposite U-shaped notches, subjected to in-plane bending do not include the effect of length as a significant parameter. This work demonstrates that below a threshold value, defined as transition length, these stress concentration factors cease to be valid and, notably, also demonstrates that below this threshold the magnitude of the stated factors may be significantly larger than existing values; a fact that may have important consequences for the accurate estimates of fatigue life. The finite element determined, theoretical stress concentration factors for the stated geometry and loading, including length as a parameter, for the existing range of the notch radii values, as well as an extended range of these values are reported and are presented in the standard graphical form. The corresponding values of the transition lengths were computed and are reported as well.