I’m not quite sure why, but planners tend to come up with interesting ways to calculate the average slope of a site. It seems like using triangles would be best, but sometimes they want to use contours. Unfortunately Civil 3D doesn’t have a way to calculate the Average Slope of a surface based on contour lengths.
So to fix this deficiency I’ve created a report to perform the calculation for you. The report utilizes the formula in the above picture. The report is installed into the Toolbox, and the user executes the Average Slope Calculation. After selecting a surface the user is prompted to select a point to place an AutoCAD table. The table can then be exported to a csv file if needed in another format. The precision of the numbers is taken from the settings of the drawing.
Contour – Surface Commands Settings > Add Contour Labeling Settings > Elevation
Area – Surface Feature Settings > Area
Grade – Surface Feature Settings > Grade/Slope
Here is the report in action.
The cost for the report is $200/site or office. To purchase the report either use the button below or send me an email. Orders are usually processed within 24 hours.