pouring trench foundations in stages

[sm_jamieson]

Is is possible to build trench foundations in stages, or does it have to be in one pour? For example, using a cement mixer, can it be done over several days? Obviously the joins would be of concern. Simon.

[Rob Morley]

No room for a few blokes with wheelbarrows to get mix from the truck to the site?

[AlexW]

Sounds a lot easier.

You can also get concrete pumped in on a boom/crane, the big ones can span a house. Not sure how pricey though.

Alex.

[ben]

Not recommended matey due to foundation sink over the years, one block of concrete could sink in the middle...any idea what would happen then? :-(

[AlexW]

Pour in layers and/or reinforce maybe?

Alex.

[Rick]

Again probably a false economey, round my way ready mix is 60 quid a cube, if you buy 6 cubes in one go. The materials alone won't be far off this price, unless you buy direct from the quarry in 20 tonne wagon loads.

I beleive you need a 200mm of steel mesh into each piece to be considered a join, but you will need an engineer to confiorm this, with will cost 100 quid alone.

Rick

[Capitol]

What dimensions?

Regards Capitol

[Chris Bacon]

A concrete pump is very very pricey.

[Chris Bacon]

It can certainly be done in stages, time factors and the (possible) use of retardant admixtures are important. Call up Readymix or someone (even if you don't intend to use them) and get some advice.

[Paul Andrews]

The readymix I used came in a lorry that couldn't tip to the furthest foundation trench ( 5metres from the closest), so I built myself a sturdy chute, 3.5m long, with one end resting on a workmate, the other overhanging the far trench. lorry could easily reach closest end of shute - worked like a dream! Took about forty minutes, if I remember, from start to finish.

I would have been there forever mixing my conrete and it would have needed a lot of reinforcement: 5m3 of pour.

Just remember, you will be lifting the equivalent weight of the trench at least once over (filling the mixer) and more likely closer to twice over - getting it where it would need to be and you'll have an inferior solution to a single pour.

If you can possibly use readymix, I would. I was considering mixing the concrete myself untill I realised how long it would take and the sheer effort involved.

Paul

[Hugo Nebula]

On 20 Sep 2005 09:18:07 -0700, a particular chimpanzee named sm [e-mail] randomly hit the keyboard and produced:

Make sure the joins are away from corners and changes in levels. Put

12mm diameter reinforcing rods in the ends of your trenches to act as a key for the next one, and scabble the surfaces of the exposed concrete for a better key.

[Lobster]

Having recently laid a (very small) floor slab on my own using a mixer, I'd say "too right"!

Another potential solution if you have limited access to the site is to find a minimix-type supplier; there are Transit-sized flatback trucks around with little mixers on the back for delivering readimix

David

[Rick]

I have limited access to my site, what we did was put the readymix at the top of the track, use 2 dumpers to ferry it down, and a mini digger to get it from the dumpers to the holes.

Rick