How to achieve - Paraty house style cantilever from reinforced concrete,

[studiodm]

Hello,

I am currently working on a house similar to Paraty Style house of Marcio Kogan, and the cantilevers are quite long, they come up to 6 m. I don't want to have a very thick slab, and I also don't have option to additional support in front. How is it possible to achieve this. I don't have much experience with similar, I will be using reinforced concrete. I would appreciate any advice for this mater

Thanks

 

[KootK]

Post-tensioned concrete might be an attractive option.

I like to debate structural engineering theory -- a lot. If I challenge you on something, know that I'm doing so because I respect your opinion enough to either change it or adopt it.

 

[hokie66]

I would think that in the pictured structure the side walls cantilever. The wall beside the stair at the lower level also provides support for the slab. Hard to tell about the upper slab. A 6000 cantilever is not achievable without a lot of depth in some of the structural elements.

 

[thaidavid40]

The cantilever floor beams will need appreciable depth, to limit both stress and total deflection, as @hokie66 pointed out. But keep the floor slab to the bare minimum thickness that meets the criteria, to limit the supported dead weight. I sense a very expensive design, and construction, here!

Thaidavid

 

[studiodm]

Thank you all for your comments, I think there might be an option for a prestressed concrete solution, or steel beams inside the concrete, which one do you think its better? Where it is going to be built, I am not sure they have much of an option for a prestressed concrete, I am aware it is going to be quite expensive though.

 

[BUGGAR]

I like the way they tapered the floor, wall and roof slabs to make them appear thinner.
I'm curious about the foundation. I bet that will cost more than the structure?

 

[dhengr]

Studiodm:
Precast conc. planks, with topping, bearing on the top and bottom chords of some full story heigh steel trusses. The trusses are anchored into the foundation in the back span, and they are fabricated with a positive chamber (upward) out in the canti. section, so that they are approx. flat with a little more than the DL loading in place.

 

[drawoh]

studiodm,

I am not an expert, but I just looked up "Paraty Style house of Marcio Kogan". The thing is embedded into a mountainside. Probably, this helps their foundations a bit. The side drawing views show a flight of stairs going down from the front of the upper section, right where I would want to place a column.

I hope your contract is cost plus!

--
JHG

 

[Jc67roch]

I agree with outside walls as deep concrete beams for the cantilevers and the slabs designed to span between them (maybe with some interior walls to help). You might also try to design as a concrete "hollow tube" shape overall! However, this would require a LOT of temporary shoring until all concrete was connected and set to act as one. OR get as precast sections and post tension together - like bridge sections. Good luck with this one!!! Wish I had clients that could afford cool, ambitious projects like this!

 

[jike]

I think that you would be surprised at the actual slab thickness because your eyes are fooled by the "thin" tapered edges. I agree with the thought of the cantilevered side walls with a post tensioned slab spanning between them.

 

[studiodm]

Thank you all for your comments,

@dhengr I am considering this option, it seems reasonable. Although I was discussing with the client, and he is insisting on ICF blocks, I am just quite unsure that they can provide some of their products for this type of a house.