Pouring slabs at different times - connect with rebar/helibar?

[Nolobes]

Hi,

First time post - go easy on me.

I'm building a side-return extension on my victorian terrace which also requires the removal of two internal walls which divide the kitchen into 3 rooms.

To keep the house functional and to save money, my plan is to work my way back from the end of the house (the actual kitchen is in the first third currently).

I need to dig out the entire floor and start it from scratch, so was planning to set the slab in stages, to minimise the disruption.

I have the end of the house dug down and ready to go (once I've put down the hardcore, blinding sand and DPM).

My question is, can I create a form to prevent the concrete from reaching the wall which I'll be removing, but set in it some steel rods which will protrude from it horizontally, then when I've removed the wall, do the same again for the 2nd third, but allow that pad to set up to the first and as a result envelop the steel rods? Does that make sense?

I'll try and explain a different way. Can I lay the pad for the whole room in stages, if I connect them in some way? If so, how would I do that?

Thanks.

 

[KenGMac]

Nolobes, good evening.

Short answer is yes you can, If you pour the [say] first area of slab, up to what is / was called up here a "Stop End" then yes you can at the time of pouring the concrete insert [generally] 20.mm bars through the stop end so that there is a [sort of] 50 / 50 split in the length of the steel 20.mm bar between the concrete and where the next concrete pour will poured sometime soon.

If you Google something like "construction joints in concrete" there will pop up a load of different images, all basically like the description above.

The stop end is generally timber, through which you can bore slightly over sized holes for the steel dowels, when the concrete is poured but NOT set tap the steel dowels in to the holes, keep them [reasonably] level then tap them lightly to make sire of a good tight grab by the setting concrete. Removal of the stop end can result in destroying parts of the stop end, be careful here so as not to damage the top surface of the newly poured concrete, the latter is easily done on fresh set concrete.

Ken.

 

[Nolobes]

That's great, thanks. What length of steel do you think would be required to connect 2 x (3000mm x 2000mm) pads 100mm deep?

 

[KenGMac]

800.mm to 1.0.m gives you a grab of 400 / 500.mm into each pour.

Ken.

 

[jeds]

If you want to look one up, these types of joints are normally called 'daywork' joints.