Double Shapes- Analysis vs. Modeling

In Revit Structure, the structural beam, column and brace are regarded as bar elements, and the analytical mode lines join with one another at the nodes, shown below,

        

For some steelwork however, the joints require the elements not to be overlapped with one another while two or more elements are connected, e.g., as the following image indicates, two C shaped elements are placed in parallel to bearing the forces or bending moments. If two beams are put there, there will be two parallel analytical lines from one node to the next, and it will cause the analytical error.

To solve the issue, two steel elements are created in one family, and a spacing is set to control the horizontal offset of the beams, shown below. As a result, both modeling and analysis purpose are satisfied in the project.