I was chatting with an architect about a new project he's doing in utrecht and he mentioned a "ball floor"... or rather a "ballen floor" which seems to translate into this. he didnt know the english but im guessing its "ball floor". anyway what is it? i assume its a lightweight concrete floor used to reduce the structural weight as the core is small?

What kind of building is it? That might give us a leader...

its a tall building, built over a train station.

its a tall building, built over a train station.
ballen is the dutch verb to play ball...

perhaps its a games floor:lol:

I was chatting with an architect about a new project he's doing in utrecht and he mentioned a "ball floor"... or rather a "ballen floor" which seems to translate into this. he didnt know the english but im guessing its "ball floor". anyway what is it? i assume its a lightweight concrete floor used to reduce the structural weight as the core is small?

http://www.bubbledeck.com/

basically the bits in between reinforcement are just concrete. concrete is heavy, so replace with a void former, in this case a ball. This reduces the selfweight of the slab making it more economical. this is mainly used in deep slabs spanning greater distances. not sure if it has been used in the UK yet. but once it has been tried once, you will probably see a lot of it

I feel enlightened :)

So it's like hollowcore, but without the core :?

I feel enlightened :)

So it's like hollowcore, but without the core :?

try the link. its actually just like an insitu pored slab on formwork with the balls cast into it.
Hollow core is extruded off site and then brought to site as a solid concrete slab

thanks chompo. this is the building in question that uses it, its in holland by the way. i was chatting to the architect about it and he said "ballen floor" and wasnt sure of the english for it. i thought it could mean ball floor and then realised "i dont know what a ball floor is" but only the next day. rather than sounding an ignorant mong to him i thought i'd ask here.

http://www.skyscrapernews.com/images/pics/985UtrechtsCurvingTwinTowers_pic1.jpg

Bubbledeck .. that's a new one on me. It claims to be 65% of the weight of a standard in situ slab, with the same bending strength, 90% of the stiffness although offset by the reduced self weight, but much reduced theoretical shear of 60% of a standard slab, although shear is not often reached as it's bending that is usually pushed to the limit first. Sounds like an interesting product, nice and simple but effective, I wonder if we'll start to see it widespread in the UK?

well i think the reason for this was this particular building does apparently have very narrow cores to maximise the floorplates inside. combined with the fact its over a train station and you can see the need to keep the weight down.

try the link. its actually just like an insitu pored slab on formwork with the balls cast into it.
Hollow core is extruded off site and then brought to site as a solid concrete slab

The basic difference between hollow-core and BubbleDeck is that hollow-core is a one-way spanning system, while BubbleDeck is a biaxial slab (as it is concreted on site) spanning in arbitrary direction. Hence it doesn't need any beams thereby creating a slim flat slab structure.