What is the best way to take a surface from Civil 3D and make it into the Finished Design surface in TBC-HCE so that I can apply site improvements to it?
To be able to apply Site Improvements in BC-HCE you will need the 3D Breaklines for the areas where the Site Improvements will be applied and in BC-HCE they will need to be a part of the SUrface Model. You have two choices
1) You can output a 3D DWG File from Civil 3D that contains all of the Points and Breaklines / 3D Lines that you want to form the surface model from, and then let BC-HCE create the "Design Surface" from those directly. On import of the DWG you will need to convert all of the 3D Breaklines into Linestrings (see Trick to do that below) and then change the Properties of all the Lines that you want to use to bound Site Improvements to Sharp and Texture Boundary. Now build your surface model from the Points and Lines and get your Design Surface as you want it. Now you can apply Site Improvements to the Surface (you can use the Takeoff Processes to do that or just the process of applying SIte Improvements followed by Create Subgrade Surface for the surface interfaces that you need to create e.g. Bottom of Engineered Materials or a specific surface layer like Bottom of Asphalt Pavement etc,
2) You can selexct the Surface along with the 3D Breaklines and Points that make the surface in Civil 3D and output the Surface and Poingts and Breaklines to a LandXML File. Then you import the LandXML file into BC-HCE and basically do the same as above. The downside to LandXML is that you will lose the Layers, Colors and Linestyles of the CAD file - but if you have any Highway Geometry in the model then you should use LandXML method at least for that data.
If you have a lot of CAD Lines or CAD Polylines and you need to convert them to Linestrings, the easiest way to do that is as follows
1) Draw a piece of Text a long way from the project (at least 100') and enter the text as e.g. 100.000
2) Use the Elevate Lines command and use Text as the method, select all the lines that you want to convert and then select the text that says 100.000 - make sure your distance tolerance (offset Tolerance is set to a number smmaller than the distance from the text to the nearest line - i use 0.001 for this to be sure - that way the Text cannot elevate any of the lines.
The trick here is that to elevate lines we make them Linestrings and then change the elevation based on the text we find near the lines within the search distance - because your text is 100' away and your search distance is 0.001 it never finds any matches so no elevations get changed, however all the lines are now Linestrings.
Now keep the lines selected, right click and go to properties and find the property called Surface Sharpness and select Sharp and texture Boundary.
Now create the surface model from the Points and Breakline Data that you imported.
Once you have a Surface you can use the Takeoff Workflow or you can use the Quick approach by using the Apply Surface Site Improvement command to apply the site improvements defined in the MSI Manager to the areas of the project bounded by the model Breaklines that carry the Sharp and Texture Boundary setting.
On completion of assigning the Surface Site Improvements you can then run the Create Subgrade Surface command to build the Surface Interfaces that you need for the Project. You can create e.g Bottom of Engineered Materials of a specific Layer Top or Bottom (the layers are defined in the Site Improvements in the MSI Manager).
Hope this helps - let us know if you need more information
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