Recessed manhole in gravel

[ChristineLove]

What's your opinion on using a recessed manhole in gravel, and filling it with gravel? One contractor who's quoting for me says it's fine, another says there's a danger of the edge becoming exposed, sharp and dangerous. (Amazingly good site, btw. Thanks for the huge effort you make)

[cookiewales]

What's your opinion on using a recessed manhole in gravel, and filling it with gravel? One contractor who's quoting for me says it's fine, another says there's a danger of the edge becoming exposed, sharp and dangerous. (Amazingly good site, btw. Thanks for the huge effort you make)

couple of items to be careful with 1 you need to fix gravel in tray with some strong sand and cement with some sbr glue and treat gravel as well for tray.gravel on steel is a no no very slippy.2 haunch up sides of tray place gravel on haunch all should be fine cookie :;): ??? ps you can use thin recessed tray as for tiling

[Pablo]

I've done it plenty of times the way cookie mentions above with no problems and it looks and behaves fine. The thinner ones are cheaper and just as good.

[GB_Groundworks]

i did a product test for tony for a round 350 recessed man hole cover for soft landscaping areas, was plastic but designed for turf or gravel.

think they are launching the product very soon

[ChristineLove]

Thanks, Guys.

Can you explain in a bit more detail how to secure the gravel in the manhole cover, please? The contractor said loose gravel is no problem (!!) and said I can use PVA glue if I'm worried about it (??). I am assuming it will be a shallow cover/tray - do I just mix gravel and bonding agent together and spread the mixture in to fill the tray? Will it stick permanently to the tray?

[cookiewales]

Thanks, Guys.

Can you explain in a bit more detail how to secure the gravel in the manhole cover, please? The contractor said loose gravel is no problem (!!) and said I can use PVA glue if I'm worried about it (??). I am assuming it will be a shallow cover/tray - do I just mix gravel and bonding agent together and spread the mixture in to fill the tray? Will it stick permanently to the tray?

if you read my first reply it tells you what to do and pva is no good outside must be sbr cookie :;): :;):

[lutonlagerlout]

TBH cookie I cant make head nor tail of what you said,and i have been at it for 26 years :;):
the way i kinda read it is fill the tray with some strong mortar with SBR mixed into it and then scatter gravel onto that?

does that sound half right?
cheers LLL

[cookiewales]

TBH cookie I cant make head nor tail of what you said,and i have been at it for 26 years :;):
the way i kinda read it is fill the tray with some strong mortar with SBR mixed into it and then scatter gravel onto that?

does that sound half right?
cheers LLL

that's about the jest off it but a bit more fiennes 4 to1 sharp sand cement some sbr in water wash some gravel in sbr and water solution place on top of mix then spot board on top tap lightly till hits top of frame. and end result should be fine :;): :;): happy manhole

[simeonronacrete]

A few things...

How deep is the tray?
An sbr (Ronafix) modified screed would need to be a minimum of 6mm.
What traffic will it take? If cars, then the tray may flex. If it does, the bond between the screed will be stressed and may break, thus the infill mortar may fail. It may be advisable to use a recessed tray with a steel mesh welded to the base to aid adhesion.
As to the success of bonding/glueing aggregate to the top of the mortar, this may be a hit and miss as the mortar will need to be quite wet to hold the stones rather than have the stones bounce off from the surface of a semi-dry mortar. But, a wet screed is more at risk of shrinkage and cracking.

An option is to lay the Ronafix modified screed 3mm below final level, leave it with a profiled finish, let it cure for 7 days, then give it a light mechanical key to remove any loose material, and apply Ronadeck Fast Grip on top of the screed.

If you want to know more, give us a call.



Edited By simeonronacrete on 1275336755