Creating Transitional Depth Site Improvements Between Areas

This one comes up from time to time.

You have an airport runway that has a set of material layers to be constructed and a taxiway or apron area that butts up against the runway that has the same material layers but different material thicknesses. The engineer has designed the area between the two areas with a 2’ transition zone over which the material thicknesses vary from one side to the other. In addition both sets of layers may have a Geotextile layer that needs to be laid that we want the area quantity of that may or may not be present in the two adjacent stacks of material.

This will use the Material and Site Improvement Manager to define the materials and the site improvements for the Runway and the Taxiway / Apron and also the transition zone between the two areas.

The key issue that I see relates to the thin membrane between the two areas. TBC has a limit that anything less than 2.5mm thick (0.0984252 feet) does not need to be present on both sides of the solution yet allow the other common materials to transition. The key is to enter the thickness of this material at something less than 2.5mm or 0.09 inch (i.e. 0.1 inch is too large so use 0.05 inch and you will be fine.

The process steps include

Use MSI Manager to create the materials needed (Concrete, Aggregate, Sand, Membrane)
Use MSI Manager to create a Site Improvement for the Runway area
Use MSI Manager to create a Site Improvement for the Apron and Taxiway Area
Use the MSI Manager to create a Site Improvement for the Transition Area and set the Transition Flag on the Site Improvement

Create the 3D lines for the surface areas
Add them to the design surface
Set the Surface Sharpness property of the lines in the surface to be Sharp and Texture Boundary

Add the Site Improvements to the Runway, Taxiway and Transition Zone
Build the subgrade surfaces

View in 3D or with Surface Slicer View

Video shows you how

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