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cadmastr
2004-10-29, 07:11 PM
I have created the alignments, profiles, contours of several roads and cul-de-sacs of which intersect in several places the main new road. the problem is that I have contours crossing each other instead of interpolating (?). I have also created a surface using all new contours created for each road...the intersections at best is just lovely...NOT...

What suggestions would you have for me...

I still haven't been able to work out my culdesac solving problem..

thanks for your help

MHultgren
2004-10-31, 04:27 PM
You can approach this in a couple ways. One is to create a cross section of your curb, gutter and pavement at 1:1 scale, place 3D plines at the elevations desired along the back of the curb of the Cul-De-Sac and Curb Returns and then project your section along these Back of Curb plines.

Another approach is to create 3D breaklines for your curb, flowline, back of walk, and centerlines and then trim your TIN at the BCR and ECR of the returns. Place a point at the CL intersection and use the TIN and your breaklines to define your surface(s). This will work in the Cul-De-Sac also.
The thing to remember when creating the 3D lines is when prompted for the spacing along a curve, make sure it is a small increment so your surface looks smooth. I use a spacing of .5 for returns and CDS. The linework is a little choppy, but a 40 scale plan does not look too bad. If you want a smoother curve, make the spacing smaller, like .1 or something. Remember though, the smaller the spacing, the larger the file will be when you build your surfaces.
HTH

mjfarrell
2004-10-31, 05:58 PM
Good point on adding the additional vertices,
however there is no reason the linework for
your face and back of curb lines would get choppy.
These plan lines could be regular cad objects
(nice for snapping to when prompted for Point on Curve)
and the 3d polylines used to model the surface are
not even displayed in the plan view.