A probabilistic interpretation of the Miner number for fatigue life prediction

Abstract

The Miner number M, used as a tool for lifetime prediction of mechanical and structural components in most of the standards related to fatigue design, is generally accepted as representing a damage stage resulting from a linear progression of damage accumulation. Nonetheless, the fatigue and damage approach proposed by Castillo and Fernández-Canteli, permits us to reject this conventional cliché by relating M to the normalized variable V, which represents percentile curves in the S-N field unequivocally associated to probability of failure. This approach, allowing a probabilistic interpretation of the Miner rule, can be applied to fatigue design of mechanical and structural components subjected to variable amplitude loading. The results of an extensive test program on concrete specimens under compressive constant and load spectra, carried out elsewhere, are used. A parallel calculation of the normalized variable V and the Miner number M is performed throughout the damage progression due to loading allowing probabilities of failure to be assigned to any value of the current Miner number. It is found that significant probabilities of failure, say P=0.05, are attained for even low values of M, thus evidencing the necessity of a new definition of the safety coefficient of structural or machine components when the Miner rule is considered. The experimental and analytical probability distributions of the resulting Miner numbers are compared and discussed, the latter still providing a nonconservative prediction in spite of the enhancement. A possible correction is analyzed.

Probabilistic S-N fields based on statistical distributions applied to metallic and composite materials: State of the art

“…75 Correia et al 76 and Blaso´n et al 77 evaluated the cumulative fatigue damage of riveted metallic connections with puddle iron from Fa˜o bridge for different percentile curves with the purpose of interpreting the Miner number for fatigue life prediction. The same path was made by Ferna´ndez-Canteli, 78 where this author used the probabilistic fatigue model to evaluate the cumulative fatigue damage of the concrete.…”

Evaluation of Energy-Based Model Generated Strain Signals for Carbon Steel Spring Fatigue Life Assessment

“…The linear Miner's rule is widely adopted in fatigue analysis due to its simplicity. Since the tolerance of fatigue analysis is high, this method is very safe and acceptable because the deviation was below 10% [34]. The fatigue life of the coil spring could be predicted with known material properties; steel alloy SAE 5160 is a type of carbon steel which is widely used in coil spring products, with the properties of the material shown in Table 1 [22,35].…”

Probability Distribution Type for the Accumulated Damage from Miner’s Rule in Fatigue Design

“…Previous studies within the literature have proposed the Normal [4], Log-Normal [5], 3 Parameter Weibull [6] and Fréchet [5] distribution types for the accumulated fatigue damage from Miner's Rule. However, these studies have relied on an assumed distribution type of ' ' from S-N data sets [4,5,6], along with an assumed S-N curve shape [5]. However, the choice of distribution type for is often debated [2] and cannot be assumed a-priori for new S-N data sets.…”