Life Prediction of Structures by Means of ESA and CAE

The risk of fatigue damage concerns structural components, structural knots and even whole structures subjected to random loading. This can initiate the accumulation of fatigue damage in critical points of the structure, growth and spreading of fatigue cracks and, eventually, fatigue fracture. Final failure of structural components may have fatal consequences. Calculation results regarding the accumulation of fatigue damage in supporting structures are commonly highly useful when investigating the causes of an operating failure or in further efforts to adjust principal parameters due to device adjustment (for instance in order to increase lifting capacity of cranes) or when estimating residual life of a device after some failure or an overhaul. This paper offers a few examples of how the process of fatigue life prediction can practically be applied. Fatigue life is determined by means of ESA (Experimental Stress Analysis) and CAE (Computer Aided Experiment). Nowadays, for the purposes of fatigue life evaluation CAE systems enable the combination and the interaction of various methods altogether: ESA, FEM (Finite Element Method) and MSS (Mechanisms System Simulation).