Creating the Required Alignment From the Plans (PI Method)

In order to convert the sections from 2D CAD or PDF sections, we will require the alignment. In this case the alignment (Horizontal and Vertical) was provided in a form best suited to the PI data entry method.

When creating the alignment from the plans, I typically tabulate all the data from the plans in Excel first and then use that information to build the alignment in TBC - you can do it direct from the plans into TBC, but it is harder to trace back to find a problem if you do it that way.

Note: When tabulating in Excel, it is often a good idea to ref the Page number of the PDF file where the data line was extracted from, in case when entering the data you find an issue - maybe a Typo or a missed data item and you need to go back and cross check the tabulation data.

The following videos show how to Import PDF Files of the Plan Sheets into TBC and to georeference them using Coordinate Grid locations. It then shows how to enter the PI information (the frame of the alignment as a check. It then shows how to create the full alignment using the reference frame as the source of coordinates and then looks at reviewing the TBC computed Geometry against the information provided on the plans.

The second video shows the process of extracting the Vertical Alignment Data, Tabulating it in excel and then using that information to build the vertical alignment.

Now that you have all of the alignment data created, you are ready to execute the CAD or PDF Section conversion process to move the sections from 2D drawings to 3D linework that can then be used for surface and corridor modeling purposes. Note that the PDF sheets in the Plan View will help you determine why there are gaps in the cross sections (typically for Bridges or Tunnels) so you know where to bound your surfaces and to create “gaps” in the earthworks model.

This hopefully shows all of the major steps in converting Cross Sections into a 3D model. Once our VDC team has finished with the Model, I will present the results here as well so you can see the finished result.