Techniques for Modeling Curved Framing

Revit models curved beams with represented at a true arc; however, like most structural analysis software, Robot Structural Analysis Professional requires arcs to be discretized into linear segments. In Revit there are two options to consider when transferring curved beams to Robot. The first approach is to leave the Analytical Beam with its default true arc geometry. The Revit-Robot link will automatically discretize the arc into linear segments that are approximately 1 foot in length. This approach is fine for curved beams in isolation; however, the discretization does not account for intermediate members framing into the curved beam. Thus, duplicate nodes may be created and instability introduced into the model. For a better outcome, select the Approximate curve parameter of the Analytical Beam and indicate the level of discretization. Furthermore, select the Use hard-points parameter to force discretization at the nodes of intersecting framing. These discretized segments will transfer to Robot Structural Analysis Professional as shown in Revit. Once the curved beams are transferred to Robot, use the Members dialog to create “superbars” out of the linear segments. Robot will then view this “superbar” as a single element for design optimization rather than many individual elements. Robot will not transfer the discretized segments back into Revit. Effectively, the Revit-Robot transfer of curved beam in a one-way trip from Revit to Robot. Thus, any updates to curved beam will need to be done manually in Revit.

 

Comments

[Pete Umbaugh]

That's excellent! Thanks for sharing.