Walls: co-ord structural + architectural models ?

[MKEllis]

Hi,

[Edited: Apologies - partly duplicates query from this post: From October 2013 that makes a few suggestions]

We're looking for some guidance on the best approach for coordinating the architectural and structural model elements.

We have linked models, shared coords set up, and the structural model has the steel frame, structural floors etc. set up, whilst the architectural model has walls, windows, floor finish (screed+insulation) etc. The models are playing together nicely for the moment.

The main issue that we have hit so far - is what to do with walls - Who models them - and what is the best approach ?

I understand that there will be some duplication in the models - walls for eg. the Structural engineer also needs to place walls in order to place foundations etc.

But how should we deal with this wall duplication ?

We have tried amending our wall (a cavity construction) to leave an air gap where the structural concrete block appears - so that this links in from the structural model - but the windows do not cut this linked in wall (not sure if the engineer needs to establish this cut in his model ?)

Do you just live with a duplication of the walls - and filter the engineer's one out in the linked model ?

What about quantities - if you have duplication across the two (or more) models, does this pose a problem in measurements ?

Any guidance would be really appreciated, many thanks

Martin

[MKEllis]

Been doing some more research on this and it seems that there are as many 'solutions' as there are opinions on it.

For the moment, I think we will run with either:

1. Maintain walls in two parts - the structural core (blockwork) in the structural engineers model, and the remainder of the wall (finishes+thermal) in the architects model. For this approach what is the best way of forming an opening in the structural wall to accomodate a window opening hosted in the architects wall ? Other than forming the opening, it allows more flexibility for tweaking the structural core in the structural engineers model independently of the rest of the wall - ie cut outs for steel, bracing, stopping wall core at underside of steel beams - whilst allowing the rest of the architectural wall (And finishes) to remain continuous.


2. Model the whole wall in the architectural model - select it as 'structural' then copy/monitor it into the structural engineers model - select "copy original" for the wall type - and tick for door/openings to be automatically replicated. This allows the structural engineer to place foundations etc. using this copy/monitored wall. (Interstingly - it seems to mirror the wall type for some reason when we've tried this approach).

Still not sure whether this is a reasonable approach, whether we are missing something obvious. And we still haven't figured out how to cut an opening in the core wall outlined in 1.

Any ideas appreaciated.

Thanks

Martin

[MKEllis]

We're going with option 2 above.

But, our structural engineer doesn't want the whole cavity wall shown in the structural model, just the structural core (215mm block).

It seems that it is possible to substitute a 215mm Blockwork wall in place of the whole cavity wall build up in the structural engineers model via the Copy Monitor process (by using the settings, and selecting the substitute wall as 215mm). It will need a bit of setting up to make sure it is in the correct laterall position (rather than the default wall centerline).

Is this a sensible approach ? - it seems that it retains the openings, and looks correct. I am not sure on the structural functionality in Revit with this approach, will the engineer lose anything in doing it this way (any impact on the analytical model)?

Should he instead model his own wall (but then we are back to the - how do you inherit / monitor openings from windows / doors from the architect's model) ?

Thanks,

Martin

[rosskirby · Accepted solution]

Your approach is generally what I'd recommend.  The structural engineer should copy/monitor your walls, which include the core CMU and the architectural finish materials, and in his/her model, substitute whichever wall type he uses to represent structural CMU walls (which would not have the architectural finish materials).

[MKEllis]

Thanks Ross.

We are feeling our way into file sharing in Revit - our structural engineer is also fairly new to Revit.

Does copy/monitoring the wall in this way (with a substituion of the wall type with a simplified core-only version in the structural model) have any impact on the analytical model ?  In other words - is there a disadvantage when compared to having the structural engineer model relevant part of the wall himself (apart from how to form openings in this wall in a linked/monitored fashion) ?

I think I'm going to have to put a tutorial guide together for everything that we are piecing together so that we can share it amongst our consultants.

Many thanks again,

Martin

[rosskirby]

---

@MKEllis wrote:

Does copy/monitoring the wall in this way (with a substituion of the wall type with a simplified core-only version in the structural model) have any impact on the analytical model ?  In other words - is there a disadvantage when compared to having the structural engineer model relevant part of the wall himself (apart from how to form openings in this wall in a linked/monitored fashion) ?

---

Not as far as I'm aware, but I'm not a structural engineer, so there's that.  As you said, the disadvantage with having him/her model the structural core wall and you model separate walls is that you have to manually join the geometry in your model in order to get hosted families to cut through all the walls, and you have to manually align/lock all your walls.  If there are only a few such walls, then it may be worth it, but I would consider it a time-suck to have to do it throughout a huge project, where there's never enough fee to cover it.

[constantin.stroescu]

Hi Martin,

 Unfortunately for me , our structural engineer offices still use AutoCAD, so  my personal experience is limited in this realm, but I keep hoping they will try one day to make a step forward....For the moment I try to prepare my mind for this collaboration ....so I keep diging...

maybe this links from AU (Autodesk University ) can throw some light on the problem, if you'll make time for watching them:

http://au.autodesk.com/au-online/classes-on-demand/class-catalog/2011/autodesk-revit-structure/bette...  

and

http://au.autodesk.com/au-online/classes-on-demand/class-catalog/2012/autodesk-revit-for-structural-... ( especialy Module 3,4...)

Constantin

[MKEllis]

Thanks again Ross - sometimes it's just good to know that you are on the right track.

We are working up a section of the building - just a couple of structural bays - to quite a high level of detail to dry run the file exchange and set up to familiarise ourselves with the issues before embarking on the whole model. We're needing to go into some detail to tease out the problems but it seems to be working quite well (as in - it is raising a fair number of coordination workflow queries).

Martin

[MKEllis]

Hi Constantin,

thanks for the links - I had seen those before (the AU on demand classes are great) - they are good tutorials for the wider collaboration steps (especially the one that looks from both structural and architectural sides) - but they stop short of some of the detailed workflow practices.

This was another of the useful tutorials: Who owns what - best practices for coordinating all disciplines

Collaboration with BIM really does shine a light on some of the idiosyncracies in the way architects / structural and MEP engineers work too.

Thanks again,

Martin