Crack Detection in Railway Axles Using Axle-Box Vibration Measurements: Experimental Investigation Using a Full-Scale Roller Rig

In this paper, an experimental investigation is carried out to assess the possible use of axle-box acceleration measurements to identify the presence of a transverse crack in railway axles, detecting components of axle vibration occurring at frequencies that are integer multiples of the axle’s frequency of revolution (N × Rev components). The experimentation was performed propagating the cracks of different dimensions induced into a pair of railway axles mounted on a freight wagon by means of full-scale roller rig tests. The results show that the 3 × Rev components of the horizontal axle-box acceleration is well correlated to the size of the crack and less sensitive to the effect of disturbances induced at the roller-wheel contact with respect to the vertical acceleration. Hence, they represent a promising possibility for the continuous monitoring of axle integrity. Specifically, the obtained experimental results suggest the possibility of detecting cracks with sizes larger than 11–12%...