StruSoft StruXML Revit enables two - directional communication between Autodesk Revit and StruSoft FEM-Design. It is a powerful, but at the same time easy to use, tool that transfers the analytical model along with its properties between the two programs.
One can fully benefit from the link, when the analytical model in Revit is well prepared and contains all the necessary information. And this part - preparation of the analytical model, appears to be a rather common problem.
The majority of support issues that I receive from our users does not apply to our Add-In itself (for which we provide a full customer support), but to the analytical model issues (which in theory is not really StruSoft's area of expertize). Anyway, I am always trying to advise the customer and at least, give some hints about the possible issues with the model. I will also try to collect some ideas in this article.
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Second part of this article is available here.
Situation 1: There is no analytical model in my Revit project , or some of my elements do not have analytical model.
Solution:
Analytical model is an integral part of any structural element in Revit Structure. By structural elements I mean:
- Structural Column
- Structural Framing: Beam and Brace
- Structural Wall
- Structural Floor
- Structural Foundation: Isolated, Wall, Slab
a. Enabling analytical model
Each of the structural elements have an Instance parameter called "Enable Analytical model". If the parameter is checked, the analytical model will be present for the particular element.
b. Analytical model visibility
If you enabled analytical model for all structural elements in your project but you still can not see them, the problem may lie in the visibility settings. Revit gives an opportunity to create many different views of the model, and to decide upon visible elements in each of the views separately.
If you want to see only the analytical model in a current view, go to "Visibility/Graphics Overrides" that can be found in the Properties dialog of a current view.
First go to Model Categories tab and uncheck "Show model categories in this view" not to see any physical elements in the given view.
Then, go to Analytical Model Categories tab and check "Show analytical model categories in this view". Make also sure that each category listed below is checked.
Situation 2: Analytical elements in my model are not connected.
Solution:
Revit offers a few tools to adjust the analytical model. One can change the position of analytical element by modifying the "Analytical Alignment" settings that are found the properties dialog of each analytical element, or can modify the elements manually.
Solution:
Revit offers a few tools to adjust the analytical model. One can change the position of analytical element by modifying the "Analytical Alignment" settings that are found the properties dialog of each analytical element, or can modify the elements manually.
Auto-detect adjustment is the default adjustment method and it is carried out automatically when you build the model. While the physical model is created, the placement of analytical elements is automatically adjusted in order to receive the most accurate analytical model.
Auto-detect adjustment is performed in accordance to the tolerances that are defined in the "Analytical Model Settings". They are:
- Horizontal auto detect: it is the maximum horizontal distance between the analytical and physical model that can be used when Auto-detect justification method is chosen.
- Vertical auto detect: it is the maximum vertical distance between the analytical and physical model that will be used when Auto-detect justification method is chosen.
If the "Auto-detect" adjustment method does not create a consistent analytical model, or if you want to place your analytical elements in a specific way, use the "Projection" method.
You can decide the location of analytical model of an element in relation to the grids or levels of the structure, or in relation to the physical element itself. In case of linear analytical elements, you can decide upon the horizontal and vertical references separately for each of the ends.
Look at figure below where, as an example, possible horizontal and vertical references in case of an Analytical Beam are shown:
c. Manual adjustment for slabs, beams and columns
Apart from the methods of analytical model adjustment described in the previous paragraphs, Revit allows you to manually adjust analytical elements.
Upon choosing "Analytical Adjust" command (→ Analyze tab → Analytical Model Tools panel), the "Edit Analytical Model" mode is displayed.
Click an analytical node in order to activate it and reveal its 2D handles, then you can drag the node.
Read more about manual adjustment in Revit Help.
d. Manual adjustment for walls
"Wall Adjustment" command can be accessed from the "Edit Analytical Model" mode. It allows you to manually adjust an analytical wall in relation to the position of another analytical wall, beam, column or node of analytical floor.
Read more about manual wall adjustment in Revit Help.
Situation 3: How can I check if my model is well connected?
Solution
There is no one perfect way to check if the analytical model is well connected. Especially when the model consist of few hundreds / thousands of elements is it difficult to judge it. But there are couple of ways that can be combined or used depending on a case, to check the analytical model connectivity.
a. Filtering analytical nodes
Analytical node is
present at each end of the linear element (beam, column) and at each corner of
a surface element (plate, wall). Analytical nodes are usually not displayed by
default, even if a Show analytical model
category in this view command is selected. To display
analytical nodes in your structure, select "Analytical Nodes" category to be
visible in the given view as shown in figure below.
Every
analytical node has a new instance property called Connection Status. It is a read-only parameter that displays the
connection status of an individual analytical node. The connection status of
each analytical node can be: Connected (Auto-Detect
or Manual), or Unconnected.
The Connection Status parameter, when involved into a proper Filter definition, can be used to
determine the connectivity of the overall structure. Watch this video showing how to set the filters.
When the filters are set, one can easily see if the all the nodes that are suppose to be connected, are actually connected. In the example below one can see that some of the nodes marked in red are unconnected (connection between column-beam, or beam-beam). Please keep in mind that nodes at the end of columns / beams or unconnected corners of walls or plates that are meant to be unconnected will also be displayed in red.
In case of large models it is a good practice to create many analytical views. In each of the views one can only display chosen elements e.g. only analytical beams and columns, only analytical slabs and walls, only analytical walls, etc. This way it is much easier to control the connectivity of a certain group of elements. You can also apply the filters to each of the view separately.
c. Export to FEM-Design and mesh
Another good practice is to export a part of the model to FEM-Design, even if it is unfinished yet. In FEM-Design one can easily prepare the mesh on the imported model and check how good it is. In case there are some small displacement between the elements, FEM-Design will throw a warning about it along with an exact coordinate point of the problematic spot. This gives you a chance to fix the analytical model in an early stage and possibly not copy the error to next storeys.
