To apply Site Improvements to create Subgrade Surfaces you do not even have to use the Takeoff Workflows. The rules are as follows
- The lines that you want to use as a boundary for a Site Improvement have to be a part of the surface to which you are applying the Site Improvements.
- The lines that you want to use as a boundary for a Site Improvement have to be 3D and will need to be linestrings. If you have CAD Lines or Polylines, you can convert all of the lines in one pass using the Convert to Linestring TML Command (Use TML Status from Rockpile Solutions website to download and install the TMLs on your PC if you do not already have them).
- The lines that you want to use as a boundary for a site improvement have to be tagged in their properties as Sharp and Texture Boundary in the Surface Sharpness field
The lines do not have to be closed polygon areas, but collectively a group of lines that meet the criteria above need to form a closed area - i.e. you can have 4 separate lines that touch or cross at the corners of a square, and provided that there are no gaps the Site Improvement will flood to the square and set the Site Improvement Property on that area.
The application of the Site Improvement and the creation of the Subgrade Model takes care of the minor offsets required to eliminate vertical step flags in the subgrade model. You do not have to offset the lines to work this process. That will likely cause more problems than adding any value.
The Materials that make up the Site Improvements will normally be defined in the Earthen Select Category or a User Defined Category in the Materials and Site Improvement Manager (MSI Manager). e.g. Asphalt, Concrete, Sand, Gravel, Aggregate etc.
The Site Improvements will be defined in Categories of Site Improvement within the MSI Manager. A Site Improvement is the stack of materials that is to be found in that area - e.g. a Gravel or Aggregate Base, a Sand Layer and an Asphalt or Concrete Layer. The Site Improvement defines the stack of Materials and the thickness of each material layer.
To apply Site Improvements to a Surface Model, use either the Takeoff work processes, but if you aren't doing Takeoff and only want a subgrade adjusted model, then you can use the Apply Surface Site Improvements Command. This will ask you for the Surface to which you want to apply the Site Improvements. It will ask you for a Name for the Site Improvement e.g. Road Pavement, it will ask you for a layer - each Site Improvement is represented by a point that carries the Site Improvement Attributes. The Point will be placed on this layer. I use SITE - SI Markers as my layer for this and I have it in the 99 - SITE DATA layer group. It will ask you to select the SIte Improvement (from the list of Site Improvements that you have defined in the MSI Manager and it will then ask you for a location for the Site Improvement - place the point in the area that you want the Site Improvement to be applied - eg the Road or the sidewalk or building pad etc. You will see the color that you defined for the Site Improvement in the MSI Manager will flood the area to indicate the area that has the Site Improvement - if it floods out of the area then you have one of the following issues
- One or more of your lines does not have the Sharp and Surface Texture applied
- One or more of your lines is not 3D
- One or more of your lines is not included in the surface model (use the Selection Set - Members of Surface XXX in View Filter Manager to check that)
- You have a gap between lines where the Site Improvement flooding can squeeze through and flood an adjacent area.
Once you have applied all of your Site Improvements, you can use the Create Subgrade Surface command to create the Subgrade Adjusted Surface for any Material Layer in the Site Improvements. Note that the Material Layers will be like the Top or Bottom of Sand or Aggregate or Asphalt or Gravel etc. Typically model the Bottom of the Material Layers that you need surfaces for. The surface created will be either a continuous surface or a surface made up of islands e.g. if you did base of Sod for Parking Islands, you would have one surface with lots of islands - one for each parking island.
If you just want the bottom of the lowest subgrade in each area where you applied a Site Improvement and Finished Grade in between where no Site Improvements were applied, then use the Bottom of Engineered Materials option to create that surface.
Note that if all you care about is the base of subgrade, then all you need in the MSI Library is one Material called Subgrade and then a number of Site Improvements, one for each total depth of subgrade materials - so for example an area covered in 6" Asphalt, 4" Sand, 6" Aggregate would be a total of 16" (1.33') thick. So a Subgrade called Subgrade 16" which has one layer of Material Subgrade that is 16" thick would cover the need. Then you would just create Subgrades like Subgrade 6", Subgrade 10" Subgrade 12" Subgrade 16" and then just apply the one that is applicable in each area, then create the Subgrade Surface using the Bottom of Engineered Materials and you will be good to go.
This whole process is captured in the video download link below
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