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Modeling
About Archicad's design tools, element connections, modeling concepts, etc.

Slab and wall intersection

Anonymous
Not applicable
Hello everyone. How can i do slab and Wall intersection at outside of slab?
7 REPLIES 7
Marc H
Advisor
If you use the 'collision method' for the wall/slab intersection (intersecting them by overlapping them), the building material priority values will do much of the work for you. If you already did this, you may want to check the building material priority rankings. I find these are not always what they should be. For example, if one uses 'steel framing' (higher rank than concrete) instead of 'lightweight metal framing' (lower rank than concrete), it will produce a poor result.
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Marc H
Advisor
In follow-up to my reply, I recreated your situation and have the materials merge properly by first checking the core and skin building material priorities against each other, then colliding the wall down over the slab. I did this in section view to better see the results. You could then apply the same parameters from the successful wall to the other walls in plan view.

Note: I find it useful to create different building materials for different real-world situations. For example, I have one for FR GB and one for regular GB so they do not merge when intersecting. I assign the FR GB a higher priority, even though they are basically the same material. This helps to better predict the results when you use your composites. There are no doubt other methods, but I find this one simple and easy to manage.



The GS video may also be helpful:

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Lingwisyer
Guru
By the looks of it, you have the slab set to "core top" and the wall at +0 to story. If you want the wall to cover the end of the slab, you will need to extend the wall below the story to meet the bottom of your slab composite.



Ling.

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Anonymous
Not applicable
thank you for answers. i think they work but what about quantities about wall? I think it changes bec wall will be at top of the slab?
Lingwisyer
Guru
If the Intersection Priority of your slab core is stronger than that of your wall core, it will clip the wall core, so only your exterior skin will be extended.



Ling.

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Barry Kelly
Moderator
rocknkaya wrote:
thank you for answers. i think they work but what about quantities about wall? I think it changes bec wall will be at top of the slab?

The quantities should be fine.
Give it a test.
Model a wall and slab that intersect and check the quantities.
Now separate them and see if the quantities have changed.

Barry.
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Anonymous
Not applicable
ok i will try it. thank you for all answers and give your time.
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