How is the class of a curve determined if the high rail has varying super elevation measurements?

When determining the class of a curve, especially when the high rail has varying super elevation measurements, the best approach is to analyze the difference between the measurements. This method allows for a more accurate assessment of how the varying super elevation affects the curve's dynamics. By subtracting the difference between the highest and lowest super elevation measurements, one can determine the critical factors that influence the safe passage of vehicles on the curve, which is essential for maintaining safety and operational efficiency.

Utilizing the difference provides insights into how the curve may behave due to the variations in elevation, directly affecting aspects like speed limits and wear on the track. Other methods, like averaging readings or using standard charts, do not consider the specific variations present in the measurements and may lead to less precise conclusions about the conditions of the curve. Consulting with an engineer can be valuable, but the primary determination of class based on these values ideally relies on a quantitative assessment of the measured differences.