topic Re: Slab Edge in Modeling

Slab Edge

Anonymous — Thu, 25 May 2023 15:39:41 GMT

Two questions: 1) How do I get rid off the line separating the slab from the thickened edge, which is a profile. Both are structural concrete; 2) If the priority of concrete is higher than earth, then why doesn't the concrete footer cut the earth automatically? Thanks.

Re: Slab Edge

Steve Jepson — Fri, 17 Apr 2015 00:03:55 GMT

As with anything in ArchiCAD, there are many ways to get what you need. And you always can.

You could use Solid Element Operations on the mesh your using for the soil.
Footing and Stem wall are Operators, Mesh the Target - Subtract.

As for the thickened slab edge and slab - you may want to consider merging them into a morph so they can be all one monolithic element. ?

This is a curious detail. Why is the slab edge thickened?

Re: Slab Edge

Anonymous — Fri, 17 Apr 2015 00:21:55 GMT

Steve,

Thanks. I will use the SEO to subtract the footing from the mesh. But that is what I did for the wall. I was just curious about the role of priority in this aspect, because if it works for many materials, it should for the mesh.

As for the thickened edge slab, even if it is a non-structural slab on grade and it does not support any bearing load, I always thickened the edge of slab so that when it is loaded with anything heavy it will hold, including differential settlement. In this case, the slab is for a garage.

Re: Slab Edge

Barry Kelly — Fri, 17 Apr 2015 01:59:53 GMT

So long as you have used the same Building Material for both the slab and the thickening then they should merge in section with no need to connect or convert to morphs or any thing else.
If the slab is a composite (as mine is here even though it only has one skin) then it must use the same BM as the thickening in the composite settings.
My thickening is just a simple slab with an angled edge but it could have also been a composite.
They must also touch exactly top to bottom.
If there is a gap or they overlap then you will see the line of the top and bottom surfaces.

Unfortunately the footing (slab) and mesh do not interact automatically in section (3D).
You must perform a Solid Element Operation on them.
There is no Priority Based Connections for meshes.

Barry.

Re: Slab Edge

Anonymous — Fri, 17 Apr 2015 02:19:27 GMT

Barry, thanks for the response. The slab and the profile are both concrete, and the slab is not a composite. The problem was the fact that the complex profile was saved and used as a beam. Once I edited the complex profile to make it a wall and not just a beam only, the two merged. Thanks again.

Re: Slab Edge

Barry Kelly — Fri, 17 Apr 2015 02:33:55 GMT

Cheikh wrote:
The problem was the fact that the complex profile was saved and used as a beam. Once I edited the complex profile to make it a wall and not just a beam only, the two merged.

I have also done it where the thickening was saved as a complex profile as a beam only and it still merges in section.

The good thing about using complex profile is it can clash (overlap) with the slab and it will still merge - unlike if both are slabs.

Barry.

Re: Slab Edge

Anonymous — Fri, 17 Apr 2015 02:48:51 GMT

Barry, I am baffled. After editing the complex profile and made it a beam only, it merged with the slab as you said. So I am not sure then what the problem was, but it is solved. Question: The "Use Building Material" is checked but greyed out. Why?

Re: Slab Edge

Barry Kelly — Fri, 17 Apr 2015 03:01:31 GMT

You need to select the fill in the profile editor to activate that option.

I didn't notice that this post is in the 'Schedules' section of the forum so I have moved it to the "working in Archicad' section.

Barry.

Re: Slab Edge

Anonymous — Fri, 17 Apr 2015 03:04:05 GMT

Ok, Barry. Thanks again.

Re: Slab Edge

Steve Jepson — Fri, 17 Apr 2015 21:04:34 GMT

The one element I never use for a garage slab is a Slab.

Garage slabs have a slope, and usually multiple slopes if you model the slope on each side of the garage door to prevent water traps. Sometimes they have a floor drain too. That, and for a slab that has special geometry on the bottom, the regular Slab is never adequate. This is why you may want to consider making it into a morph at some point. Not just for the graphics.

I start with a roof for the sake of uniform thickness and slope.

The complex profile beam is good because you can give it a slope to match a roof/slab.

In the end, my garage slab ends up being a morph because there is no other single element that can have all of these things I want, and is easy to adjust for each new project I re-use it in.

Re: Slab Edge

Anonymous — Fri, 17 Apr 2015 21:31:56 GMT

Steve, thanks for the input. You made a very good point. I am just finding out that as much as we want to use parametric tools, we often have to revert to converting some into morphs and keep going. Thanks again.

Re: Slab Edge

Steve Jepson — Fri, 17 Apr 2015 21:57:56 GMT

I think a Slab object would be very useful and not that hard for some GDL guru to make.

It could have slab edge, slope, number of nodes on the edge we could adjust vertical to make additional slopes, reinforcement options, type of fills under it, control joint spacing, floor drain option... perhaps all that needs to happen is to make a request for it ? It would be something we could use for all kinds of slabs. Sidewalks, driveways, patios, decks...

I like the idea of this as an object so we could make special configurations and save them as Favorites.

If there was such a Slab Object, I am not so sure I would use it as much as just copy and paste form other project and tweak to fit. ?

For all I know, there already is a Slab Object.

Your garage slab could be modeled with just beams or roofs.

Being able to put a custom edge on a roof or a slab would be very useful too.

Re: Slab Edge

Anonymous — Mon, 20 Apr 2015 03:21:38 GMT

Steve
It doesn't actually need to be an object on it's own.
Slab Accessories have given us the power to do this and MANY other things for years.
Being project builders, the accessories save us easily around 3 or 4hrs per project, at around 15 projects a week. That's a lot of time saving!
Graphisoft NEED to promote this functionality more!

For an example I helped a junior draftee create and use a full waffle slab and footing setup,
in around 2 minutes. That's with the draftee stumbling through some settings.
The beauty of it is though, as the floor slab changes, so does the footing and waffle!

Re: Slab Edge

Anonymous — Mon, 20 Apr 2015 13:26:07 GMT

Kristian,

Thanks for chiming in. Very interesting. It would be great if you could find a way to show us how you did. My first problem, though, is getting the tool to work. I have the Accessory installed but when I try to use it on a slab, it shows "Missing Slab Accessory Objects." How do I fix the missing slab accessory? Thanks.

Re: Slab Edge

Anonymous — Mon, 20 Apr 2015 17:54:24 GMT

Hello Cheikh,
It may be that you did not download the "Accessories Library" when
you downloaded the goodies add-ons.
How to do this may be different for your version of AC but in my version
it is done the following way.
Go to the Help menu, select the "Goodies" link which will take you to
a web page where the accessories add-ons are listed.
Notice that you have to download the version of each for your operating system
and AC version.
What is not clear and is critical is you have to scroll all the way to the bottom
of the page and download the "Accessories Library".
I hope this helps.
Peter Devlin

Re: Slab Edge

Anonymous — Mon, 20 Apr 2015 19:03:45 GMT

Peter, thanks. It turned out that I needed to just add the Accessories Library to the Library Manager. Now It works.

Re: Slab Edge

Anonymous — Mon, 20 Apr 2015 19:39:45 GMT

Hello Cheikh,
Thanks for posting back in response to my suggestion.
I am glad it worked.
Many on this forum do not let us know if a suggested solution worked or not.
Leaving us wondering and frustrated with the lack of information.
Peter Devlin

Re: Slab Edge

Anonymous — Mon, 20 Apr 2015 20:39:20 GMT

Peter, you are welcome. My rule of thumb is that if someone takes the time to provide a post with some suggestions, the least I owe them is a courtesy response of the outcome. This also helps others who may stumble on the post and wonder whether the suggestion worked on or not. BTW, have you used the slab tool the way Kristian described it. That sounds neat.

Re: Slab Edge

Anonymous — Mon, 20 Apr 2015 21:30:36 GMT

Hello Cheikh,
You wrote "have you used the slab tool the way Kristian described it".
I have not and I don't know if the accessory object can be configured
to make a deepened slab footing. I use a library part,I wrote for the purpose,
in the case of a level slab, and in the case of a sloped slab (roof)
I specify a sloped cast in shoulder in the stem wall to support the
edge of the slab. I model the shoulder by putting a narrower wall
on top of q wider wall. The slope in the bottom and top of the two
walls is accomplished using a very thin roof to trim to roof the walls.
It occurs to me to use a narrow roof with one edge sloped placed
under the slab edge to form the deepened footing at the slab edge.
This will work for sloped as well as level slabs. Now, of course ,
we can use complex profile walls and beams to make a stem wall with shoulder.
Thanks,
Peter Devlin

Re: Slab Edge

Anonymous — Tue, 21 Apr 2015 03:09:05 GMT

Hi Cheikh

We us the 4D Library here and so the footing accessory has been developed extensively by Ben Cohen. It is quite Australia specific but it is hugely parametric. Ben also makes a roof accessory that is even more amazing!!

To use the accessories though, select the slab/s you want to add the accessory to and
then under Design>Design Extras>Accessories>Slab Accessories, select footing accessory and have fun.