Cumulative Fatigue Damage: CDM-Based Engineering Rule and Life Prediction Aspect

Abstract

Cumulative fatigue damage analysis plays a key role in life prediction of elements and structures subjected to field loading histories. A general methodology for fatigue life prediction of metallic materials under variable amplitude loading is proposed in this paper. A novel theory of cumulative fatigue damage is presented. It is based on Continuum Damage Mechanics approach which relates the damage rate to that of cyclic loading through the damage function. A new damage function related to isodamage lines and remaining life aspects is analyzed. The final result is a nonlinear fatigue damage rule. The nonlinear damage accumulation rule proposed in this paper improves the deficiencies inherent in other rules and still maintains its simplicity in the application. The relationship with other formulations is pointed out together with the advantages of the proposed model. A number of fatigue damage rules can be derived as a special case of the model developed herein. A wide range of fatigue data available in the literature as well as from the laboratory are used to validate the proposed rule. The agreement between prediction and experiment is found to be excellent. The prediction results are also compared with existing fatigue rules.

Cumulative Damage and Life Prediction Models for High-Cycle Fatigue of Metals: A Review

“…Batsoulas [71] introduced the concept of hyperbolic isodamage lines. He aimed to overcome the invalidity of the straight S-N isodamage lines observed when near the axes.…”

Fatigue Reliability Analysis of Wind Turbine Drivetrain Considering Strength Degradation and Load Sharing Using Survival Signature and FTA

“…The resultant mean amplitude-frequency histogram of the bending stress of the sun gear is presented in Figure 12a. Researchers proposed some fatigue damage rules, like linear, bilinear, and nonlinear rules [43,44]. Among these, the Miner linear rule [45] is generally accepted in engineering practice.…”

Nonlinear fatigue damage accumulation and life prediction of metals: A comparative study

“…Notice from Schijve and Yarema and Batsoulas that the number of damage nuclei will cause the load interaction effect which is larger under the higher loading stress. In addition, the number of damage nuclei produced by different loading stress levels will lead to the change of damage accumulation, and this effect will increase with the larger difference between the stress levels.…”

“…In engineering practice, fatigue failure of mechanical components and structures often occurs under variable amplitude cyclic loadings. [1][2][3] Fatigue life prediction of these components has become a critical issue for ensuring their operational reliability and structural integrity, especially under complex loadings. [4][5][6] In general, fatigue damage accumulates with increasing number of applied loading cycles, which causes the decrease of residual life of these components.…”

“…In engineering practice, fatigue failure of mechanical components and structures often occurs under variable amplitude cyclic loadings . Fatigue life prediction of these components has become a critical issue for ensuring their operational reliability and structural integrity, especially under complex loadings .…”