I have back filled some drain tranches (and round an ic) with pea gravel, I now need to make the level up to the current soil level. The area will then get a concrete slab poured on it. It is a back yard so only have to cope with people walking on it.
The soil that has been dug up is rather fine and sandy, it is OK to put it well compressed in the tranches over the pea gravel – or will it over time just run into the gaps between the pea gravel?
(One option I have thought of is to rake some cement into it as I put the layers in.)
Fine soil/sand over pea gravel
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seanandruby
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Is it a grity sand or a sand/soil type that (probably by now with weather ) turns to liquid when wet?
As dug material for back fill is usually stockpiled and sealed by tracking in with a digger, or haunched and smoothed off with the back of the bucket to keep it dry, on a small redidential site it is nest covered over to keep it dry. Any material that too clayee ( is that actually a word ) , or if your sand/subsoil is the type that has turned liquid then it will be useless now and uncompactable so will need mucking away and replaced with more solid material like mot, crush and run, or concrete.
As you can imagine soil types are different over the country. If it is ok to use then maybe place a layer of geo textile over the gravel if your worried it will trickle down.
As dug material for back fill is usually stockpiled and sealed by tracking in with a digger, or haunched and smoothed off with the back of the bucket to keep it dry, on a small redidential site it is nest covered over to keep it dry. Any material that too clayee ( is that actually a word ) , or if your sand/subsoil is the type that has turned liquid then it will be useless now and uncompactable so will need mucking away and replaced with more solid material like mot, crush and run, or concrete.
As you can imagine soil types are different over the country. If it is ok to use then maybe place a layer of geo textile over the gravel if your worried it will trickle down.
sean
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lutonlagerlout
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seanandruby
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Never had any complications when using sand under and over gas mains etc: hydrocompaction can be a good thing in many cases. It is in effect having a cover slab over the trench. Mucking away good s dug backfill in favour of importing unnecessary material is both costly and wasteful. As suggested, if the sandy soil is not suitable then by all means go for a more robust material. Other things to consider is your pipe shallow and then will need concrete surround.
sean