OpenRoads Designer - Corridor Contours Do not Tie into Existing Contours

Hello. 

I am having issues getting the proposed contours from a corridor to tie into the existing contours. Please see the screenshots and scenario below. 

At STA 736+10, the End condition seeks and ties to the existing surface as desired. *Note How the proposed contours tie into the existing contours prior to STA 736+10 (left of the vertical cyan line)

At STA 736+12.5, the end condition does not tie to existing surface. This results in the proposed contours to the left of the cyan line not tying into the existing surface. This is the case from STA 736+10.01 to STA 736+14.99.

At STA 736+15.00, the end condition ties back into existing surface. 

Ultimately, I need the proposed contours on BOTH sides of the red notch to tie into the existing surface. There appears to be a 5ft section (between STA 710+00 and 715+00) where the end condition does not solve to existing surface. My template interval is 5ft. I have tried changing to the template interval with no luck. I have also tried adding Key Stations with no luck. 

If anybody has any thoughts that could lead to a solution, I would be VERY grateful. 

  • At 736+10 your end condition approaches the existing ground from beneath; I suspect that is the situation prior to this station as well.  At 736+15 it approaches from above.  When your hinge point emerges from beneath existing ground, the end condition will abruptly catch at the bottom of the slope.  No matter how many template drops you have, you'll have the same issue with the contours not tying in.

    You could:

    1. Drop a conic slope (Model Detailing tab in 2020R2) at the point where the hinge point emerges.  I've never used this so I don't know how effective it will be, but it is conceptually an appropriate method and should provide the most realistic model.
    2. Add an end condition that will tie in the second time it encounters the existing ground.  This will change your model upstream of 736+10 but it will tie in to the existing ground continuously.
    3. Live with it.  Is the material and construction cost worth the effort to clean up the model in this location?

    There are other considerations for this area though.  For instance, how does the wall affect construction sequencing?  Following from that, will field conditions match your existing ground model at the time the slope is built?

  • Tip: Use the "Key Station" tool place custom Template Drops at odd locations. Instead of decreasing the interval (which may unnecessarily bog down the corridor), place Key Stations in areas that you want to densify the corridor.

  • At STA 736+12.5, I am guessing that you are looking at an interpolated section - which means the corridor wasn't processed at that station.  I am guessing you manually typed in that station to view the cross section - instead of scrolling through the cross sections with the arrows.  When you scroll through with arrows - you only view the processed template drop cross sections

  • At STA 736+12.5, this is definitally the case.  Place a few template drops in that area to see better results.  basically there is like 15' difference between calculated end conditions between two adjacent template drops.  The area inbetween the 15' difference is interpolated. 

  • I agree that it could be an interval thing.  The way I see it, if the model had infinite intervals, then all contours would tie in exactly to the existing ground.  But what could be the case:  there is likely NOT a template drop thats placed exactly where a proposed major contour meets the existing ground.  It is likely that major contours are meeting the existing ground between template drops.  The model and contours between template drops are interpolated from the adjacent drops.  In other words, the corridor is not being processed where major contours meet the existing ground - which is why it appears disconnected.