Why no priorities for Slabs and columns?

[Achille Pavlidis]

Maybe I'm getting paranoid, but i want to understand why there aren't priorities for slabs and columns, and why it is impossible to get a perfect outcome in 3d views and elevations.

In the attached image you can see a simple structure i have modeled to help me understand the process.
It is a single story building, consisting of columns, beams, slabs and walls.

I have assigned different layers for each element (i.e. a layer for columns, a layer for beams, etc), and tried different layers priorities between them.

At the end of the various attempts i have reached to the conclusion that the best result comes when all the different layers have the same priority. And the result is what you see on the attached image.

But as you can see in the red circles, there are many snags that are visible.
There are "boxes" that form in the angles where there is intersection between column-beam-slab.
Similar snags formed also with walls and beams, but by assigning different priorities, the redundant lines disappeared.
It would be nice to have the same ability to assign a different priority to the slab and/or the column to avoid these snags.

I know it is impossible to avoid some "cosmetic" work on the elevations, but i'm trying to eliminate as much as possible.

What is your opinion on this?
Do you face the same problem?

[Erika Epstein]

Do you have beams embedded in the roof slab?
When I recreated this, I only had 3 beams where there is no roof and did not reproduce your problem.

[Achille Pavlidis]

yes, i do. In concrete structure this is the correct way to design the beams.

[Barry Kelly]

This may be related to a problem I have been complaining about since version 10 I think.
Used to be fine back in 8.1

Beams sitting on the edge of a column that continues up behind it do not mitre correctly.
Beams on there own are fine.
Straight beams are fine.
It is only in a corner situation.
One beam will cut away corectly but the second beam seems to undo part of the cut on one side of the referenc line.

Solid Element Operations are the only way I can solve the problem.

Barry.

[Achille Pavlidis]

hmm... i don't think Barry.
When i have only columns and beams i don't have this problem
The problem appears when slabs enter the equation...

see attached image.

[Barry Kelly]

Your beams have a weaker priority than the columns.
Mine have a higher priority.

If I set mine beams lower then I get the same outcome as you - so that is another solution to my problem (thanks).

But as you say slabs don't have priorites so there is nothing you can do except modeling it differently so beams and slabs don't overlap or using Solid Element Operations.

Everything (walls, beams columns, slabs & roofs) should all have their own individual priority strengths.

Barry.

[Achille Pavlidis]

Ok, i have added a Wish on this matter...

http://archicad-talk.graphisoft.com/viewtopic.php?t=33137

please cast your vote!

[Erika Epstein]

Achilles,
I can't help wonder why you are placing beams and slabs so they occupy the same space? When you do this, you get the result that you show.
How will this assembly be built?

[Achille Pavlidis]

I know it seems weird, and incorrect to have the beam entering inside the slab, but this is the only way. The assembly will be built with poured concrete on site.

In reinforced concrete structures the beam is integral part of the slab and it is calculated this way. When i get the formwork design by the structural engineer i have the beam quotations that read: Beam001: 25/50. This means that that particular beam is 25cm wide and 50cm high, including the thickness of the slab.
So it is easier to design the beam entering the slab instead of having to subtract each time the thickness of the slab (which varies very frequently) and place the beam below the slab.
And the columns also occupy part of the beams and slabs.
It would be really too cumbersome to have to subtract each time the slab thickness from the beam height and then subtract the slab thickness plus beam height from the column height, just to avoid intersections.

[Erika Epstein]

Good point. I've just modeled it so it looks right architecturally and then the engineer does there work.

With 14 we now have better interface with structural engineers,but when I sent models to them this joint did not come up as a problem. I'll ask him how it works on their end with the models I send.