Viewing Corridor Surface Slopes

Published on September 8, 2009

Viewing the corridor surface slopes allows you to evaluate the finish design surface of the corridor surface for minimum and maximum slopes.

Perform a slope analysis of the finish surface of the corridor model to locate flat and steep slopes.

In Tool Space dialog, Prospector tab:
- Expand Surfaces
- Right-click ‘Finish Surface’, select Surface Properties
In Surface Properties dialog box, Analysis tab:
- For Analysis Type, select Slopes
  Note: The criteria for the analysis are stored in this surface’s properties.
- Check Preview.
  The preview summarizes the total area for each range.
- Notice the analysis queries and renders surface triangles differently according to the slope range they fall within. A red shape indicates a surface triangle with a slope less than 0.5% and a purple triangle indicates a surface triangle with a slope greater than a 2:1 (50%).
In Surface Properties dialog box, Information tab:
- For Surface Style, select Slope Analysis
- Click OK
In the drawing area:
- Notice the red area indicates a pavement slope less than the minimum 0.5%. This situation generally occurs when a flatter longitudinal grade in the design profile and the level crown (sometimes referred to as zero high side) station in the superelevation transition coincide. This small area is acceptable.
- Notice the purple area indicates a cut or fill slope greater than the maximum 2:1. This situation was caused by the steepening of cut slopes to daylight inside or on the existing right-of-way. This may require special erosion control and soil stabilization consideration in areas where the slope exceeds the maximum 2:1.