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The wheel wear properties of heavy haul bogies running on the Da-Qin railway line were measured. The hollow and asymmetric wear are indicated. The wheel/rail contact geometry relationship was calculated on the basis of the measured wheel profiles. The dynamic simulation model using SIMPACK software for C80BF Gondola with ZK7 radial bogie and C80B gondola with ZK6 cross brace bogie was established. The hollow depth effect on wheelset attack angle and lateral force was quantified. According to the actual conditions of Da-Qin railway line, the hollow wear was predicted using a numerical method. Based on these results, the hollow wear maintenance standard was recommended. Finally, a field test for asymmetric hollow wear was described.

Many factors could affect the grinding force during rail grinding processes. Therefore, the grinding force modeling is necessary for predicting the grinding forces under different rail grinding parameter conditions. In this study, 3D models of grinding wheels were constructed based on the surface topographies of real grinding wheels. By means of simulation of rail grinding processes using the DEFORM-3D, the influences of grinding parameters on the grinding forces were explored. Furthermore, in order to verify the simulation results, rail grinding experiments were conducted using a rail grinding friction testing apparatus. Both simulation and experimental results showed that the grinding force increased with the grinding pressure and the granularity of grinding wheel and decreased with the rotational speed of the grinding wheel. A correction factor ks of 0.894 was obtained using the least square method to reduce the error between the simulation and experimental results from 10.22 to 4.42%.