Revit to Structural Analysis Workflow - Analytical Model Cleaning

[Trenno]

Hi all,

I'm interested in exploring a Revit to Structural Analysis software workflow, particularly for steel roof structures.

I'm searching for the best way to 'clean' an analytical model prior to exchanging with structural software. From the BIM techs, I hear that it will take a 'unreasonable' amount of time to accurately model steel members in Revit such that all members/nodes are aligned and connected.

So far, I've come across Bentley's solution, detailed below.

[URL unfurl="true"]https://communities.bentley.com/products/structural/w/structural__wiki/modeling-and-node-generation-best-practices
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Anybody have any other workflows or suggestions that could help? Much appreciated.

 

[serrojo]

I think this task is more a tam work than an individual, depending on the scale of the project and the number of typical solutions... you get to "clean the analytic model" but the architectural implications are to much to afford for the structural engineer.
In my experience the architects have an area measure tool based on closed/separated rooms (It is the most important thing to them!), that room separators stop working at almost any change/movement of structural elements, so they have to be well trained and guided to respect the analytical model, so you cloud work with it.
In my office there are 90% architects and 5% structural + 5% systems engineers. So today we're working on establishing a new chapter in the Office's BIM Standart, titled: " Respect The analytical Model!"
My common practice is to get the fresh architectural plans and do my modelling/analysis/design neglecting the BIM Model, and if there are changes (Always are!!) we do regular coordination between the specialties, and the results are integrated by price engineers into the collaborative model.
We're always on a tight schedule (6 months for project) so no time to waist "cleaning" a LIVE model that changes every day!

Regards

MSc. Eng. Serguei Joa
Structural Engineer
Bouygues Batiment International, Cuba.

 

[Celt83]

The revit to analysis and back process is still a pain for structural.

Common issues between all the software are:

The members maps, ie a txt file or proprietary file type that contains all of the translations to go from your revit family to you analysis software member type. Having a strong template here will help you but you'll likely be changing this file with every model and potentially every design pass unless you have every steel shape and size loaded in Revit.

Cleaning the analytical model will take longer than it is worth, you really need to model in Revit exactly as you would model in your analysis software. If you didn't model this way prepare for hours of work to clean the analytical model and then additional scrubbing in your analysis software. Two way communication between Revit and Analysis software will likely be broken in the instance of additional scrubbing of nodes, floor levels, etc. happens in the analysis software.

The most success we have had with this, and success is being used very liberally here, is going Revit to IFC then IFC to Ram Structural System but we have yet to get a truly working solution for the reverse path.

 

[Trenno]

Celt83, I'm trying to start at a very basic step - establishing simple geometry from the Revit model. I think that's what takes the longest for engineers and if draftees can attain a reasonable level of accuracy, then why not try to save the initial double up of geometry models.

I'd even be happy with a few connected nodes and sticks.

 

[Celt83]

If your looking to go to Ram Structural System then I'd suggest the IFC route.

If your looking to go into a node based software ie RISA, RAM Elements, or STAAD then I would recommend using Dynamo to export element end node coordinates to a CSV file that you can just copy paste to the x,y,z node tables in those software packages. I have a rough script than will grab all columns and framing elements and give you the x,y,z end node coordinates and proper node i and j ends for the member creation, if you interested PM me and I'll scrub out some of our in house stuff to get you started.