Browse Forums Paving & Concreting 1 Feb 24, 2009 3:11 pm If a site has uncontrolled fill and one option is to lay reinforced concrete piers followed by concerete beams around the perimeter of the proposed slab, does the concrete slab then have to be suspended on top of the concrete beams or can the concrete slab be layed inside the concrete beams covering the concrete piers in the gound? Re: Uncontrolled Fill 2Feb 24, 2009 7:12 pm What classification is you site?
Generally you'll find your engineering design will specify 350mm diameter piers into natural ground at least 400mm... These only have to be reinforced with N12 bar, but if you go over about 1800mm you typically then add a cage... The piers are spaced around 2400mm apart along the footing line, and in a grid under the slab... This N12 bar is generally turned into the footings which on a M class slab will be 400mm deep x 300mm wide... The slab, 100mm then sits on this... The other option is a waffle pod... Same deal, but with piers at 3600mm (every 3rd rib)... The pier is not tied to the slab in this case, but rather rests on these piers allowing for soil heave... Electrical Engineer... Don't hold that against me... And keen owner builder... Mainly the building part!! Re: Uncontrolled Fill 3Feb 24, 2009 7:27 pm Thanks for this info.
When you say "The slab, 100mm then sits on this... " Does this mean that the 100mm slab is poured inside the footings perimeter? Re: Uncontrolled Fill 5Feb 24, 2009 8:12 pm So the 100mm concrete slab is suspended on the footings?
That means that there is a 100mm gap between the soil (under the 100mm slab) and the suspended concrete slab on the footings? Re: Uncontrolled Fill 7Feb 24, 2009 8:40 pm Ok I think I understand now.
Lets see if I have it right (roughly!) 1. Dig pier footings and pour concrete into them with appropriate Reinforcement. 2. Dig a 400mm trench along the perimeter of the pier footings and pour concrete into the trench with appropriate reinforcement 3. Pour concrete slab inside perimeter as well as 100mm on top of trench footing Have I got this right? It's a little difficult without a sketch. Re: Uncontrolled Fill 8Feb 24, 2009 9:08 pm PM me your email, and I'll include some sketches from the Australian Standards...
Why do you need this data? Electrical Engineer... Don't hold that against me... And keen owner builder... Mainly the building part!! Re: Uncontrolled Fill 9Feb 24, 2009 9:21 pm Sure whats your email adress?
I'm studying and trying to better understand how slabs have to be on Uncontrolled Fill. I can explain further to you via email. Re: Uncontrolled Fill 10Feb 24, 2009 9:25 pm Electrical Engineer... Don't hold that against me... And keen owner builder... Mainly the building part!! 2 4332 yeah i couldnt picture it issue either, but i could clearly picture what they were doing wrong haha 2 5264 If you're in a flood zone, not only are you dealing with the importation of fill and laying it down in 150 lifts to achieve compaction, you're going to have to consider… 4 5517 |