Superelevation in Civil 3D Metric Template (Rate of change ... larger than 6% per 100m"

[bahzad_sultan]

Every time I create a superelevation in the Metric template I get this warning in the tabular editor of superelevation, "Rate of change of cross-slope is larger than 6% per 100m". I tried creating the same alignment in the imperial template, it worked fine. I think there is some issue with the template or maybe I am doing something wrong, can someone please help?

 

[ecfernandez · Accepted solution]

Hi @bahzad_sultan, welcome to the Autodesk Civil 3D Forums. Regarding your question, you should not worry about that warning if you are sure your transition length for the superelevated curves complies with the maximum relative gradient (less or equal) based on your design speed.

For instance, for a design speed of 50Km/h, according to AASHTO, it is allowed to have up to 0.65% for the gradient. Therefore, if your gradient is, say, 0.62, you'll have the warning in the software, but anyway, you can live with that since the value is not greater than your maximum (0.65%).

I hope this helps. Best regards!

[lim.wendy · Accepted solution]

Hi Bahzad,

Welcome to the Civil 3D community, and thanks for posting. As mentioned by Camilo, the warning message you’re seeing about the "Rate of change of cross-slope" being larger than 6% per 100m is generally benign, especially if your superelevation design meets the required standards for your design speed. The message might simply be indicating that the rate of change is approaching a threshold, but as long as it remains within the acceptable limits for your design parameters, it should not be a cause for concern.

If you have any other questions or if there’s something specific that seems off, please let us know!