BECO walls

Well, after a bit of head scratching the retaining walls have started to go up.
To hold back the ground and take the weight of the building the walls needed lots of steel bars in to make them strong...but it was a bit of a squeeze to get the concrete in! So we've used some blocks with more space and have been able to have a bit less steel so now it's all go. The walls get built really quick and the concrete is pumped in layers and that's it.
Can you see the nozzle putting the concrete into the wall?






















This is looking down on the concrete inside the BECO sandwich. The retaining wall will be finished soon.
We really must find out how concrete is made and what from...

BECO BUDDIES!

We've been away to visit the place where the BECO blocks are made...what are they?

Well they are 'Insulating Concrete Formwork' and what might that be?

It is a very clever way of making a concrete sandwich! Big blocks made of polystyrene (which is very light but quite strong) are put together just like LEGO blocks. They have a space in the middle and this is filled with concrete (and some steel bars to make it stronger). We have used ours to make a 'retaining wall' that's a special wall that is round the back of the nursery up against the ground and it holds the ground back, so it has to be strong and keep the water out.

http://www.becowallform.co.uk/index.html

SORRY...we didn't get to the Sharrow Festival. We have gone on our first mission, to Thorne near Doncaster to see BECO blocks being made. We'll tell you all about it when we get back.

MONSTER MACHINES IN OUR PARK!
What's all this then?

Well, we probably haven't said before but the new school is going to have 'ground source heating'. What on earth is that you might ask (as we did)?

Well, it is heating from the earth. Yeah, come on who are you kidding you might say!

A little way down the temperature of the ground is always about 12 degrees celsius because it has stored the heat from the sun, we can use this to heat the school. If you're really clever like our engineer you can make it cool the school in summer becasue you can take the heat from the school and put it back in the ground.

'Ground source heat pumps (GSHP) transfer heat from the ground into a building to provide space heating and, in some cases, to pre-heat domestic hot water. ' So says the Energy Saving Trust. You can go to their website (follow this link).

http//www.est.org.uk/myhome/generating/types/groundsource/ if you want to know more.

You can lay pipes in trenches, but our site is too small and if we did that in the park it would mess up the whole park and that wouldn't be fair on everyone else. It can also work if you drill long holes deep into the ground and put pipes into those. The school will need quite a lot (30 or 40 maybe, nobody knows yet) and our site is still too small.so we have asked the people who own and look after the park if we can have our heat from there and they have said OK.
So the machine (drilling rig) in the picture is drilling a test hole. It will be at least 100m deep!!! WOW. We couldn't even run that far! It took nearly 2 days to drill. Can you see us on the drilling rig? It was very messy as the ground is drilled there is lots of water and stuff that comes out of the hole.

When it was finished all we could see were these two pipes!

There is a special van in the park at the moment. It is connected to the pipes and is testing to see how much heat there is in the ground. It needs to stay there for 4 days to do a proper job. It will be gone before the festival as long as it is left alone to get on with the test.

CONCRETE for the nursery
26 June








We went to site with Tom to see the first concrete being poured for the building. It was the floor of the nursery. Did you know you can pour concrete? It's just like porridge!

It's bought to site in a lorry that has a big drum that goes round and round all the time to keep it mixed and stop it going hard on it's journey. You can just see the concrete lorry on the right hand side of the picture.

To get the concrete to where it needs to go you could move it all in wheel barrows and make lots of journeys but that would take ages and the school would never get finished in time. So, to make it quicker the builders use a pump. The concrete lorry puts its concrete into the pump (which is also on another lorry) and the pump has a long nozzle like a elephants trunk. Can you see the long yellow arm reaching across the picture? This puts the conctrete just where it is needed.

Pouring the concrete is called 'casting' and the floor is called a 'slab' so this was 'casting the nursery slab'. Now work can carry on to build the rest of the nursery.