FEM-Design API – Deconstruct your models and take advantage of the information in them
For a while now we have been working on facilitating the way our clients can communicate data with FEM-Design. This allows us to offer our clients our API toolboxes for Dynamo and Grasshopper that can be used to create parametric models, run iterative analyses and much more. Moreover these toolboxes can also be used for communication with physical representation models in Revit and Tekla.
New feature - Deconstruct
In the latest update of our API toolboxes we introduced the possiblity to deconstruct FEM-Design models. The deconstruct methods allows us to extract information from existing FEM-Design models, such as geometry, materials, sections, reinforcement etc. This information can be used to make changes in physical representation models in Revit or Tekla.
Our clients are usually much better than us at using our products to their true potential - and we are confident that this holds true for our API toolboxes. However, in this post we are going to scratch the surface of how the deconstruct methods can be used to take advantage of the information in an FEM-Design model and communicate this information with a physical representation model in Revit or Tekla. The following example is executed with our API toolbox for Dynamo and Revit but the principle is analogous for Grasshopper and Tekla.
Transfer information from a calculation model to a physical representation model
I many cases we want to transfer information from our calculation model to our physical representation model. Today plenty of us perform this task manually as it is difficult to connect the two models. The models usually differs as the calculation model is very simplified from the physical representation model and connecting the two thus becomes difficult; nevertheless we want to keep our calculation model simplified. However, there are some solutions to this problem. By comparing the geometry of the calculation model with the geometry of the physical representation model we can connect elements even though they might differ with regard to size, shape and placement, as long as these differences are within some defined tolerance.
In the video below we visualize how an element is mapped (connected) even though there are differences in length and placement. The mapped element is given an identifier than can later be used to access the element.
When the elements are connected we can start to transfer data from our calculation model to our physical representation model. In the video below the section and material of a connected element is updated.
This can of course be used on larger models.
The same principle can be used on other types of elements such as slabs, walls and beam. The neat thing with mapping the elements is that we can adjust distribution of for example reinforcement to our physical representation model; in other words we can transfer reinforcement to each respective element and adjust the distribution from our simplified calculation model to fit our physical representation model!
Case: prefab wall vertical joint connections
So how can this be applied on a specific problem?
When we construct prefabricated concrete structures we need to determine how and for what force individual elements shall be connected in order to create a viable structural system.The wall to wall connections (vertical joints) are typically designed as a shear connection with some individual coupling fasteners. The connection should be designed for the shear forces that occur in the connection. Moreover any tension forces that might occur must be regarded. The capacity of the connection is determined by the type and amount of coupling fasteners holding the joint together.
When type and amount of coupling fasteners have been determined for each respective connection these components can be added to the physical representation model. When added to the physical representation model schedules and material take-offs can be extracted.
How can we automate this?
Usually we have the following data:
- A calculation model (a database of information about material, geometry, loads and resulting forces)
- Coupling fastener capacities
- BIM-objects of coupling fastener components
- A physical representation model (a BIM-database)
What we need to do is to:
- Extract information from the calculation model (geometry of connections and connection forces).
- Find respective conncetion in the physical representation model by comparing geometry of the calculation model with geometry of the physical representation model according to the method described earlier.
- Determine type and amount of coupling fasteners for each respective connection by comparing the connection forces with the coupling fastener capacieties. Moreover, we can set up a condition such that a minimum amount of coupling fasteners are used and a best-fitting type is found for each connection.
- Add the components as BIM-objects for each respective coupling fastener for each respective connection in the physical representation model.
Example isolated model
The following example is created using FEM-Design 3D Structure, Revit and Dynamo (using our API toolbox). The workflow can also be established using FEM-Design 3D Structure, Tekla and Grasshopper (using our API toolbox). In order to visualise the principle arbitrary capacities of coupling fasteners and a very simply BIM-object representing the coupling fastener has been used.
Example larger model
The same workflow is of course applicable on larger models.
Want to learn more?
Please contact us if you want to learn more and find solutions to your specific problems. We offer basic courses and workshops tailor made to your specific problems. Please contact Andreas Oscarsson with any requests for offers: