Tutorial – Road Surveying – Part 1: Create Topography

Tutorial – Road Surveying – Part 1: Create Topography


hi welcome to this virtual severe tutorial video where I will demonstrate to you how you can create a topographic model of this motorway this terrain had been created earlier on with the outputs from my photogrametry process you see that I can navigate around very easily in virtual severe but actually this is just a big basket of pixels without any structure and it also contains a lot of noise which becomes very apparent when I turn on the slope color map in a real world you would expect a less bumpy road so before I can use this data in a design software like civil 3d or magnet I need to convert it to a structured vectorial data set without all that noise virtual surveyor contains the workflows to handle that process very efficiently okay start this motorway contains several lanes and you see that it’s located on top of a bank sighs you see ditches and along the entire bank you’ll find drains that deviate the water from the motorway down to the ditches I’m going to trace the brake lines along the bank and the ditches first I create a layer called banks enable a polyline drawing mode and change the name prefix to bank Izu min to the breakline that I want a trace and I start drawing I click here just before this drain after the drain and I continue to the next drain click here and after click here and after and so on now I repeat the process for the bottom bank click here here here for the drain after the drain and so on then I create a second layer to trace the break line of the ditches I call this layer ditches and then change the name prefix from bank to ditch and the line color from yellow to green Izu min to the start of the ditch and I start tracing again here like this I can do this for the other side as well all right it looks good of course I continue this process to model the entire road and then the result will look like this you see that I also added a third layer for the bottom of this ditch and on the road I’ve added these red lines here to mark the side of the road okay now I’m going to triangulate my survey and verify if it aligns well with the terrain and make sure all the objects I want to triangulate are turned on and I click triangulate when the triangulation appears I can zoom in and see if all triangles fit well with my actual topography doesn’t fit well I could add some points or add some additional lines and update the process but in this case it looks good okay then I select the triangulation level the terrain to this triangulation I make sure the reference level is sent to 3d polygons and I click modify terrain and when the process is finished the terrain fits the actual triangulation when i zoom out a little and turn on the slope color map again you’ll see that this road doesn’t contain any noise and that I have all the layers available here the describe my topography then I can export my survey and triangulation to a CAD file which the engineers can use in their design packages I will further complete the entire topography in another tutorial video I hope you enjoyed this tutorial and that it was useful and as always if you have any questions don’t hesitate to reach out to us on support dot virtual severe calm