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A simulation of fatigue crack propagation from a hole or crack undercombined axial and torsional loading was conducted on the basis of the maximumtangential stress criterion for determining the crack path. The simulation results werecompared with the experimental results obtained from fatigue tests by using thin-walledtubular specimens made of a medium-carbon steel. Fatigue cracks were nucleated at theposition of the maximum of the amplitude of the tangential stress around the hole, andpropagated straight away from the hole. The path of fatigue crack propagation from ahole or a crack followed the direction perpendicular to the maximum of the range of thetangential stress, Δσ*θ max, near the crack tip calculated from the stress intensity rangesby considering the contact of crack faces. The crack path predicted from the Δσ*θ maxcriterion was very close to that calculated from the maximum of the total range of thetangential stress, Δσθ max, calculated by neglecting the crack face contact. Thesuperposition of static mode II shear loading changed slightly the propagation path of acrack propagating under axial tension-compression. This deviation is caused by thegeneration of cyclic mode II component due to the zigzag shape of a fatigue crack.