RCF에 의한 횡방향균열 응력확대계수 계산

초록

Calculation of stress intensity factor is essential to predict remaining life of a structure, possibly fractured by a growth of crack. Repeated rolling-sliding contact loadings on wheel and rail give rise to rolling contact fatigue which brings on severe rail damage. In this paper, stress intensity factors, S.I.F. of a head checked rail are calculated by varying crack orientations, wheel and rail surface friction coefficients and crack face friction coefficients. From the analysis results, we conclude that the crack opening S.I.F.s are increased by increasing the friction coefficients of railroad surface, and in vertical crack, the maximum crack opening S.I.F.s are calculated in front of crack location. On the other hand, the maximum crack sliding S.I.F.s are calculated on the top of crack location. In slanted crack, the S.I.F.s are reduced about 50% compared to those of vertical crack by the influence of crack closure.