Analytical versus structural model

The Revit link comes down to exchanging the analytical model between SCIA Engineer and Revit.

In Revit as well as in SCIA Engineer, there are 2 different representations of the model in each project. These are the analytic model and the structural model.

The analytical model is used for calculations. It is a model in which a beam or column is represented by a single line. The cross-section that belongs to that beam or column is assigned to that line, and thus the properties of that beam or column are assigned to that line as well. A plate or wall in the analytical model is represented with a plane with no thickness, but the material and the thickness of the plate or wall are also assigned to that plane. For analysis of the structure (forces and stability), this analytical model is used.

The structural model is used for drawings and shows the volumes. For example in SCIA Engineer, the structural model must be activated to display a volumetric representation of the entire model. In Revit the emphasis lies on this volumetric representation, but this does not ensure a good underlying analytical model at all! In the end, a modeller uses this structural model to see how the realisation of the project will look like and to create drawings etc.

Now the problem occurs:
When the Revit link is used between Revit and SCIA Engineer, the analytical model is used. The structural (volumetrical) model gets neglected and therefore it is important that the analytical model in Revit is correctly constructed. So the modeller has to understand the importance of a correct analytical model of the project!

Good looking structural model can contain a very bad underlying analytical model - see the next picture - the beam is clearly not connected to the columns in the analytical model:

How it is displayed in Revit - Analysis elements have a centre line, which is displayed in Revit by coloured lines.