Manhole concrete fillet repair

[Diyisfun]

My septic tank has 3 manholes in the lawn, the concrete fillet round the edges is cracked & does not look nice.
To repair I was thinking of digging away grass & old concrete, then make a wooden frame to go round the metal lid leaving about 3" of space & then mixing concrete & replace the old.
Is this how it should be done?
also
Should I use sharp sand & cement or ballast.
What ration should the mix be?
Thanks

 

[noseall]

Sounds ok.....

.....as long as there is enough 'meat' in the concrete ring then it should be weighty enough to take care of itself.

Use 6 parts ballast to 1.5 cement with a shovel of sharp sand to give a bit of fat.

Other alternatives are to have a brick or slabbed perimeter around the frame/lid.

 

[Diyisfun]

Noseall, thanks for that I want concrete as I want to have a flower bed around it.
How deep should the mix be & do I need to put any wire in it for strength (I was thinking chicken wire as I have some).

 

[noseall]

Reinforcement would be good as long as you can get decent cover over the metal - fiddly but doable.

As long as the conc has time to fully cure and there is only pedestrian traffic then you may be fine without reinforcement.

 

[Diyisfun]

It will not be walked on, only maybe the odd fork stuck in it when Im having a dig.
Many thanks, just need to wait for the snow to clear & I can get going.