Setting Elevations of Intersection Curve from Feature Line parallel to Centerline

[bmcelhiney678153]

Hi,

I want to project elevations at a certain grade from a feature line parallel to my centerline up along a curve, perpendicular to the original feature line. This way I know for sure the slope along my intersecting roadway to the centerline is exactly 2%. Is there a way to do this using just feature lines and not in a corridor setting? Using the elevation by reference tool doesn't give you exactly perpendicular lines for projecting.

Thanks.

[BlackBox]

I want to project elevations at a certain grade from a feature line parallel to my centerline up along a curve, perpendicular to the original feature line. This way I know for sure the slope along my intersecting roadway to the centerline is exactly 2%. Is there a way to do this using just feature lines and not in a corridor setting? Using the elevation by reference tool doesn't give you exactly perpendicular lines for projecting.

Welcome to AUGI!

If you're modeling a Corridor, that is what Assemblies are for... Then you simply modify a Region's Targets accordingly (i.e., for this Region I want to Target this layer for edge of pavement, etc.).

You can model an entire surface from Feature Lines, using OFFSETFEATURE Command to account for both horizontal, and vertical shift, but why waste the project budget to do so? (rhetorically speaking)

Cheers

[bmcelhiney678153]

I'm actually dealing with gaps in a corridor at a roundabout and using feature lines to bridge the gaps. My issue is I need to project from my back of curb to front of walk which aren't parallel lines. It is similar to intersection curves, so that's why I used that language.

[BlackBox]

My issue is I need to project from my back of curb to front of walk which aren't parallel lines. It is similar to intersection curves, so that's why I used that language.

I appreciate the language you're using, as it helps us to understand your situation; however, the point remains, that you're making it more complicated than it needs to be (albeit unintentionally), IMO.

I'm actually dealing with gaps in a corridor at a roundabout and using feature lines to bridge the gaps.

Not sure how you're modeling your corridor region, but I do not experience this issue, and I have to model them (roundabouts) quite often... Perhaps there are some simple changes that can be made to resolve the matter.

More information is needed.

[bmcelhiney678153]

Thank you for your responses. Currently the way our model is set up, the corridor regions on the legs end before reaching the circulatory area region. Our circulatory area doesn't include any outer curb lines because they may not reach where the actual inscribed circle is. I know we could probably use a small corridor assembly to run along the curb, but thought it'd be easier to create feature lines out on the BOC to "fill in the gaps" that the corridor isn't reaching. This is no problem since we have elevations to tie into on either end and can easily figure out the curb elevations between. However, I'm seeking an easy way to project from my BOC to front of walk (two lines that are not parallel with one another) and get that slope to be exactly 4%. The elevation from adjacent reference wants to project to the front of walk feature line at strange angles unless I put in a bunch of elevation points on the front of walk feature line. I know I could project elevations to certain elevation points placed on the feature line by hand, but I was hoping for an easier, automated process.

[BlackBox]

Thank you for your responses. Currently the way our model is set up, the corridor regions on the legs end before reaching the circulatory area region. Our circulatory area doesn't include any outer curb lines because they may not reach where the actual inscribed circle is. I know we could probably use a small corridor assembly to run along the curb, but thought it'd be easier to create feature lines out on the BOC to "fill in the gaps" that the corridor isn't reaching. This is no problem since we have elevations to tie into on either end and can easily figure out the curb elevations between. However, I'm seeking an easy way to project from my BOC to front of walk (two lines that are not parallel with one another) and get that slope to be exactly 4%. The elevation from adjacent reference wants to project to the front of walk feature line at strange angles unless I put in a bunch of elevation points on the front of walk feature line. I know I could project elevations to certain elevation points placed on the feature line by hand, but I was hoping for an easier, automated process.

Create an Alignment over your BOC, with the appropriate Profile elevations, add said Alignment as a baseline to your Corridor, run an Assembly the maintains the desired 4% slope, and modify that Region's Target to be your Sidewalk layer.

Again, you're essentially performing the same task, now just in more steps than is necessary.



You could simplify the entire process, IMO.

You've got your approach roads Corridor Regions covered (the 'legs') based on your typical section Assembly presumably. Great. I assume that your legs end at the point of tangency for each access to your roundabout. Awesome.

To manually model a roundabout with four individual approach roads, you'll need to create five Alignments - note that there are multiple ways of accomplishing same, I'm simply trying to convey what I feel would be the simplest to grasp, and you may be advanced well beyond such an example - The first Alignment, represents the inscribed 'island' of your roundabout. The second, third, fourth, and fifth Alignments represent the non-parallel, non-standard segments that connect the outside of two separate approach roads.

First Alignment, set your Profile grades, and run your Assembly by adding your Alignment as Baseline to your Corridor - you now have an 'island'. It is up to you if this Alignment is the interior edge of pavement, or the circle representing the outer edge of pavement.

Second Alignment, this physically connects the point of tangency of one approach road to the point of curvature so-to-speak of the adjacent approach road, and should coincide with the termination of both Corridor Regions. set your tie in elevations to both the connection Corridor Regions at edge of pavement, and include any critical elevations for your roundabout's grading. Add your second Alignment to Corridor as Baseline, and run the applicable 'curb return' Assembly, Targeting both the adjacent Alignments representing the approach roads, and the First Alignment used to create your 'island' for the interior side of this new Region. For the exterior, simply Target your 4% sloped component of the Assembly to be your Sidewalk layer.

Repeat for all other remaining connections.



You now have a fully modeled roundabout, which connects all adjacent roads, and correctly grades 4% from back of curb to your sidewalk between the typical section Assembly of both adjacent Regions. Lemon squeezy... It took me longer to type out, than it would to perform the task! HaHa

HTH

[BlackBox]

Thank you for your responses. Currently the way our model is set up, the corridor regions on the legs end before reaching the circulatory area region. Our circulatory area doesn't include any outer curb lines because they may not reach where the actual inscribed circle is.

This sounds to me like you've not targeted properly - if you target the appropriate layer, and/or Alignment, the Assembly will automagically 'reach' as needed while maintaining the slope criteria you designate.

I know we could probably use a small corridor assembly to run along the curb, but thought it'd be easier to create feature lines out on the BOC to "fill in the gaps" that the corridor isn't reaching.

OFFSETFEATURE Command will account for vertical offset of Feature Lines, but by definition offsets resultant Feature Lines equidistant (not necessarily parallel). If you want to model this 'bandaid' with Feature Lines, then you need to calculate the appropriate grades at each critical location, and then edit the Feature Lines elevations accordingly before adding to your surface as breaklines.

Cheers