Experimental investigation on the rail residual stress distribution and its influence on the bending fatigue resistance of rails

Abstract This paper presents an experimental study on the residual stress distribution of 60E2 (UIC 60) rails, and its influence on the rail bending fatigue resistance. First, a brief introduction concerning the rail bending fatigue resistance and the rail residual stress distribution is given. Second, an experimental investigation using the sectioning method on the residual stress distribution over the height and in the foot of the 60E2 rails is presented. Third, an experimental investigation on the residual stresses in the rail foot by applying the X-ray diffraction method is elaborated. Afterwards, the results of these two methods are compared. The residual stresses determined with the sectioning method show better consistency with those in literature. Subsequently, the residual stress results determined with the sectioning method are considered with the four-point-bending fatigue results and integrated into a new comprehensive Smith-diagram. As a result, the residual stress distribution is found out to be decisive when determining rail fatigue resistance. It is further concluded that rail bending fatigue resistance shows a good mean-stress dependency when the actual residual stress distribution is considered.