Numerical Analysis Model for Fatigue Life Prediction of Welded Structures

Lee, Chi-Seung; Lee, Jae-Myung

Journal of KWJS 2009;27(6):49-54.
Published online January 13, 2010.

용접구조물의 피로수명예측을 위한 수치해석모델

Numerical Analysis Model for Fatigue Life Prediction of Welded Structures

Abstract

In this study, the numerical analysis model for fatigue life prediction of welded structures are presented. In order to evaluate the structural degradation of welded structures due to fatigue loading, continuum damage mechanics approach is applied. Damage evolution equation of welded structures under arbitrary fatigue loading is constructed as a unified plasticity-damage theory. Moreover, by integration of damage evolution equation regarding to stress amplitude and number of cycles, the simplified fatigue life prediction model is derived. The proposed model is compared with fatigue test results of T-joint welded structures to obtain its validation and usefulness. It is confirmed that the predicted fatigue life of T-joint welded structures are coincided well with the fatigue test results.

Key Words: Continuum damage mechanics, High cycle fatigue, Simplified fatigue life prediction model, Welded structures