Stress intensity factor for an elliptical crack under stepwise uniform load

The closed solution is given for the stress intensity factor (SIF) at the front of an elliptical crack under uniform loading on the elliptical ring. The problem solution is constructed by a modification of the Rice's variational formula for two different states on the crack sides. As the first state, the combination of the second one with the main state is taken so that the total SIF is zero. In this case, the Rice's formula is transformed to the formula corresponding the virtual displacements principle for a combined loading on the elliptical crack sides.