Surface: exclude great height drops

[j_vdvelde]

Good day,

I've been working on C3D for quite a while, but never encountered this 'problem' before.

A shape file was delivered, containing height lines for a canal. It stretches about 30km (20 miles).

The shape file is the only data I have but I have to use it.

In the picture below the lit up line is the profile that resambles the surface, that was created with the shape file. The blue vertical line resambles the side of the canal.

As you can see below, near the side of the canal the height drops quite fast. This does not occur outside and I just want the line to stop at a more logical height (no need to be the exact value)

As side information: below you can see the lit up line being the side of the canal. In the above picture it's the blue line. The white lines are polylines (!) created from the shape fale, which are used as breaklines in the surface.

 

I have used the maximum / minimum height, bus as you can see tha yould delete some actual used data.

I could trim each white line, but with 30km canal this will cost me 2 days.

Working woth a boundary also isn't verry time efficient.

Is there any more convenient way of removing any height drip steaper then, say, 1:1?

I'm a fan of Dynamo if that leads to the solution.

[Jeew-m]

Hi,

I am thinking about analyzing the surface for elevations and trace the spots with higher elevation variation. Possibly with a separate colour.

Then extract that colour triangles from the surface.

And then you can think about someway of doing it to suit your need.

[nkiakas]

Hi @j_vdvelde 

Looks like the shape files where not filtered before sharing and you loaded unwanted data.

Could you share the the shape file(s) or you DWG after importing the shape files?

It looks like matter of deleting few unwanted (garbage) points (vertexes)

[j_vdvelde]

I've attached the SHP.  Had to ZIP it, because the original file was too big for the system (82MB; 71 is allowed) . Please keep the file size in mind when importing.

The DWG I cannot attach; with the loads of stuff that's already in it, it's over 2GB in split data (13 mms files).

When you import it into Civil you'll see the edges come down to a 'point zero' as if there was a boundary in the original model. This is unwanted data indeed so if it will be erased: perfect!

Deleting the unwanted points manually would cost lots of time and we're on a budget 😉

If this can't be done fast / easy it's just too bad and we'll keep going on with the unaltered files.

[Pointdump]

Hi James,
I see the shp file, but where's the dbf,shx, and prj files?
Dave

[j_vdvelde]

There isn't a SHX, PRJ or DBF file... I just got this SHP and import with MAPIMPORT as Esri shapefile.

[Pointdump]

James,
Well that's something I've never seen before. MAPIMPORT does indeed bring those contours into the drawing. No Object Data, but each polyline has an elevation. And what's up with the dense 0.25 steps surrounding the shapefile?
I don't know a way to eliminate those dense contours. Maybe someone will chime in with something.
What part of the world does this represent? You might want to look for better data.
Dave

[nkiakas]

Hi @j_vdvelde 

I agree with @Pointdump comment above.

I imported your shape file but i can't create surface from break lines (your polylines), my system is old for tasks like this.

It looks like the shape file has only contour lines with 0.25 step. Due to the nature of the file i would suggest you to edit the file with a GIS software. I am sure you will find tools in specialized GIS software.

Also please let me know. What it tis surface 37km long, only 70 meters width, with several branches...is it an existing road? If its a road, i think you data have very low quality elevations, because the depressions are a lot along the road (if its a road). Looks like the elevations collected with photogrammetry methods, and potential obstacles (buildings/trees) creating great errors in the elevations.

[j_vdvelde]

This file is a compilation of multiple multibeam scans of a canal for river transport, located in the Netherlands.

I suspect there was a boundary around the measurements that was mixed up with the actual data, which in turn results in these steap sides.

Just removing these sides will not do the trick, as other data in the middle of the canal will be erased too.

Thank you all for helping me wowards a solution, but we've decided we're not going to edit and go on with these strange shapes. And notify out contractor this is all we have.

[Pointdump]

James,
Good elevation data at your Area of Interest to be found >>>Here<<<.
Dave

[j_vdvelde]

Thank you. This website indeed is great for environmental elevations, I'm already formilliar with it 🙂

The Geotiles contain 'AHN' data made with awsomely accurate satellite scans. These satellites however, do not scan underwater. Also, the multibeam scans I refer to, are made right after the canal was dredged to depth to serve as reference depth and is needed to check if all shores stull are stable.