Strain-based Multiaxial Fatigue Life Evaluation Using Spectral Method

To describe the impact of multiaxial service loads a power spectral density matrix of the strain tensor components has been taken into account. To determine the fatigue life some selected multiaxial fatigue failure criteria have been used. The main focus of this paper is set on the comparison of the cycle counting method and the spectral method. An algorithm used to calculate the fatigue life in the time domain as well as in the frequency domain has been introduced. The proposed algorithm has been verified on the basis of fatigue tests of cruciform specimens made out of the S355J2WP steel.