Digital simulation of environmental processes with respect to fatigue

Abstract To estimate the service fatigue life of dynamically loaded components and structures, fatigue tests with simulated loads must be carried out. This paper presents various methods of on-line digital simulation of real environmental processes, representing inputs of fatigue machines. According to the method of analysis adopted, this simulation can be based either on sinusoidal amplitudes in the form of blocks or individual cycles, or on random processes. The random process simulation can reproduce the probability density of amplitudes, the power spectral density, or both of them, depending on the fatigue damage hypothesis and philosophy of testing accepted.