Determining the safety factor for fatigue strength under regular loading

A method for calculating endurance in terms of stresses in concentration areas is presented. The method is based on the transformation of classical formulas. It is shown that the endurance in the case of a non-uniaxial stress state is not practical to determine in terms of cycle stresses reduced to an equivalent stress that can be used to calculate the amplitude and average equivalent stresses. It is suggested that the amplitude and average stresses should be determined first in order to calculate the values of equivalent amplitude and average stresses afterwards. The efficiency of the method is proved by an example. The method can be used for calculating the endurance both in the case of uniaxial and multiaxial stress states.

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