How Revit Shares Coordinate Systems with Civil 3D
In a Revit project, all elements have internal coordinates unique to that project, which only Revit recognizes. However, to ensure that the model’s position is recognized across other linked models, sharing coordinates is essential. You can export shared coordinates from only one file, which then defines the coordinate system for all other project files. Once you acquire coordinates from one file, you must publish these coordinates to the remaining files.
When importing terrain data from AutoCAD Civil 3D (referred to here as Civil 3D), a common issue arises: the coordinate systems of Civil 3D and Revit often differ. This mismatch can prevent editing of Civil 3D-created surfaces within Revit, causing frustration. The following explanation shows how to align Revit terrain coordinates with Civil 3D’s coordinate system.
First, use the already prepared surfaces in Civil 3D as a reference, as illustrated below:
By marking a specific point in Revit, you can establish corresponding reference points to define the shared coordinate system:
Use the shortcut key ID in Civil 3D to pick and record the coordinates of this point:
Next, open Revit and link the CAD file. Attach the CAD drawing to the site for future use. Customize the elevation according to the site and set the origin accordingly:
Then, move the Project Base Point in Revit to the marked project reference point and set the coordinate system elevation. Note that North/South corresponds to the Y coordinate, while East/West corresponds to the X coordinate.
Once the coordinate system is set, the next step is to publish the shared coordinate system.
Select the option to publish the coordinate system, then click on the linked CAD reference drawing as prompted. This action publishes Revit’s internal coordinate system to the linked DWG file, synchronizing it with the DWG file’s coordinates. Consequently, when importing a DWG file representing original terrain data at a mileage station, you can also import another measured DWG file based on this coordinate system directly into Revit. During import, the coordinate system can be selected for synchronization.
After confirming this setup, future imports can be directed into the shared coordinate system efficiently and quickly.
This process allows any edits made in CAD to be seamlessly imported into Revit, enabling smooth progression to subsequent steps.
Related Tutorials:
How to Add Shared Parameters in Revit
Application of Revit Project Parameters and Shared Parameters
Must log in before commenting!
Sign Up