An assessment method of the cross and vertical sections is presented based on the heavy-haul train-track coupled dynamics. The assessment error between the train longitudinal dynamics model and the train-track coupled model is discussed. Combining with the line conditions and train formations in China, the train longitudinal impulse and wheel-rail interactions in different lines are evaluated. The results indicate that the difference of degree of freedoms of the train brings the slight error in the train longitudinal forces. The vertical section with the concave curve has significant influence on the train longitudinal and lateral dynamics. Based on the assessment results for the line style parameters, some design values can be corrected.