Hello,
Ok, I know my subject sounds like a stupid question--why would one add a station equation if the ahead station is equal to the back station? The short answer: to (possibly) cut down on work later.
Can one add a station equation to an alignment in Geopak COGO where the ahead station is equal to the back station but still introduce a Region change? If so, how does one do that?
In my experimentation with COGO, I was able to create a station equation when the difference between the ahead and back station was greater than or equal to 0.01 ft. (I was working with the decimal setting set out to 6 decimals.) Is that the minimum allowable difference or can that be set to a smaller value? When I tried to station a chain with ahead and back station difference less than 0.01 ft. or zero, COGO would insert a new point like it always does, but it would not create a new region after the added point.
So why would one consider doing this?
It has been my experience that when once a vertical alignment (profile) has been set, if changes are made to corresponding horizontal alignment (chain), then a lot of manual editing is required to fix the profile. Also, if a station equation is added to a chain, there are additional difficulties when working with the corresponding profile. For a road project, this is not a big deal, usually--it's not a big deal to re-enter a profile or manually edit a profile to shift VC's.
However, I'm working on a mile and a half long multi-use path project along an existing road with limitations on space, which is forcing the horizontal alignment to weave it's way through obstacles and the vertical alignment to hug the existing ground as much as possible. The preliminary horizontal alignment had around 85 horizontal curves and the vertical alignment over 100 vertical curves (VC's). Compared to a typical road project, this is a large number of horizontal and vertical curves for one and a half miles!
I'm in the early stages of design and am looking to make my life easier later on when we get design revisions. I foresee changes to the alignment and want to avoid having to fix 100 VC's every time. To limit the effects of the changes, we are considering breaking the project into segments along the design alignment. We would like to introduce station equations every-so-often to mitigate the need to shift every VC after a revision. Therefore, I'd like to have the equations and regions already set up so that equations don't have to be added later. The thing is, we don't want the equations to appear on the plans unless there has been a revision, which is why these "preemptive" equations are being added with the ahead stations equal to the back stations.
A related article with a problem I'm trying to avoid:http://communities.bentley.com/products/road___site_design/f/5922/p/46182/103948.aspx#103948
Thank you in advance for any help or suggestions.
i am also looking for same in mx road