Concreting Floor in Earth Lagoon

[AlfM]

We are constructing a clay lined lagoon and thinking of concreting the floor. We have a bit of moisture at depth and not convinced we'll have a 100% solid base for the concrete so not ideal. So probably wet/damp clay and digging further will likely just get wetter.

What are our options for the concreting? Terram? Hardcore thickness, concrete thickness, mesh? Is it possible to almost form a 'floating' floor as in it will hold itself together as one 18 m x 18 m slab which is surely enough of a lump to be alright to drive on?

 

[BAC]

We are constructing a clay lined lagoon and thinking of concreting the floor. We have a bit of moisture at depth and not convinced we'll have a 100% solid base for the concrete so not ideal. So probably wet/damp clay and digging further will likely just get wetter.

What are our options for the concreting? Terram? Hardcore thickness, concrete thickness, mesh? Is it possible to almost form a 'floating' floor as in it will hold itself together as one 18 m x 18 m slab which is surely enough of a lump to be alright to drive on?

As clean as you can get it. Visqueen the floor, single layer of mesh and also add fibres for added piece of mind??

 

[AlfM]

As clean as you can get it. Visqueen the floor, single layer of mesh and also add fibres for added piece of mind??

How thick of concrete? Would you think the slab would stay in one piece and float on whatever was underneath?

 

[Blue.]

How thick of concrete? Would you think the slab would stay in one piece and float on whatever was underneath?

At least 6"

It wouldn't be the end of the world if it did crack (a little) I think it would be fine,just don't go horsing around with a 25t shovel in it.

 

[BAC]

How thick of concrete? Would you think the slab would stay in one piece and float on whatever was underneath?

Could always put in a dry mix blinding and then place the slab on top?

Slab depth, probably 200mm? As @eulb says, keep heavy traffic off the best you can. In all honesty, visqueen could act as a secondary liner??

 

[Blue.]

Could always put in a dry mix blinding and then place the slab on top?

Slab depth, probably 200mm? As @eulb says, keep heavy traffic off the best you can. In all honesty, visqueen could act as a secondary liner??

If its clay lined it wouldn't need it,I agree about fibres,I'd flood it with concrete,self levelling at 200mm would be a top job.

 

[Dry Rot]

My first question would be, where is the water table? My second question is, if the base is clay, why line it? Clay is impermeable to water, though it does depend. We had to construct some fish ponds and got in a specialist. We were thinking of visqueen sheets. He pointed out that we had plenty of peat on site which can do the same job at no cost. This surveyor told us that he had created lagoons in the Middle East by just scooping a depression in the sand, then spraying with bitumen. Our contractor up here (north of Scotland) created duck ponds for the RSPB and said he had never yet had to lay a membrane. He made one for us which is quite large. No lining and it is always full of water. Just thought.