Analysis of Wheel-Rail Contact Stresses Through a Turnout

The turnout represents a complex component of the track structure that generates high levels of vertical and lateral dynamic forces. This in turn results in high levels of wheel/rail contact stress and corresponding high rates of track degradation, significantly greater than in conventional track. Furthermore, the location of these high contact stresses vary as a vehicle negotiates the turnout. This paper presents the results of a series of analyses and computer simulations developed to examine the wheel/rail contact behavior as a vehicle negotiates a turnout and to determine the location and magnitude of the associated wheel/rail contact stresses. These analyses include a procedure for aligning the wheelset profile to the rail profile pair, based on the actual rail profiles, as it varies through the turnout. Using the point-by-point alignment, the analyses then determine the location of the wheel/rail contact patch and then calculate the magnitude of the contact stress profile in that patch. The result is a map of the wheel/rail contact stress as a vehicle moves through the turnout.