Effect of Vertical Wear of Unmovable Frog Nose Rail on Dynamical Wheel-Rail Contact in Turnout Zone

Abstract:

The distribution law of the vertical wear of frog nose rail is analyzed based on test data and literature， and the vertical wear profile of the frog nose rail in each level were created according to this distribution law. Aimed at the 60 kg?m^－1 rail No.12 single open turnout of ordinary railway， a heavy haul train-turnout coupled dynamical model was established based on the theory of vehicle-turnout coupled dynamics to calculate and analyze the influence of the vertical wear of the frog nose rail on dynamical wheel-rail contact in frog area when the heavy haul train passes through the turnout. The results show that the region where the top width of the nose rail is 20-40 mm is the region where the vertical wear is more serious. With the increase of the vertical wear of the frog nose rail， the maximum of wheel-rail contact force in the wheel load transition area and the volatility of contact force curve in the transition area generally are increased， even the wheel-rail contact relationship is deteriorated， and the smoothness of the wheel load transition between the nose rail and the wing rail is decreased. When the track geometric irregularity is good， the vertical wear of the frog nose rail top width of 40 mm should be controlled within 5 mm.