David Bonds

Using Station Equations for Decreasing Progression

Discussion created by David Bonds on Nov 2, 2020
Latest reply on Nov 2, 2020 by Alan Sharp

Recently I came across an issue that I'm not sure has been addressed here, but found the fix for it.


I have an alignment with 5 or so equation stations, the last one decreasing in station rather than increasing.

For example:

"Zone 5" runs from station 708+57.21 to 798+15.60, with the equation at the end being 798+15.60 (BK)/ 306=32 (AH).

From 306+32 (the start of zone 6) the stationing decreases, while left and right orientation remains the same (to the end of project, 295+00).


To achieve this I entered the equation station to complete "zone 5" (798+15.60 BK/ 306=32 AH), and created another equation station with the "Back and Ahead" stations both set to 295+00. This completed "zone 6", reversing the progression while also leaving the left and right orientation as the plans intended.

(for reference, see attached image)