An engineering method to estimate the stress and stress state including the damping ratio differences of various modes

This paper is aimed at proposing a method. This method can solve the problem of the dynamics simulation where different modes have different damping ratios. Simultaneously, the method to achieve the stress state is also presented. A finite element model of the investigated object is established. It is validated by the modal test and the strain test. Subsequently, the single-mode-frequency-division loading (SMFDL) is applied. The square root of the sum of squares is used to calculate the equivalent stress. Phase angles and statistic stress components are combined to calculate the stress state. The final results show that SMFDL is rational and the calculated equivalent stress has enough accuracy. That method to attain the stress state gives acceptable errors. Dividing the excitation into more sections is a good approach to improve the accuracy of the stress state estimation.