Boral Rapid Set No-Mix Concrete is a proportioned blend of dry aggregate, graded sands, cement and additive mixture suitable for post hole applications where lower than normal strength is acceptable.
Boral Rapid Set No-Mix Concrete cannot be mixed in a wheelbarrow or mechanical mixer like normal concretes.
The additive used in the mix reacts instantly with cement allowing very little to no mixing time or compaction.
Calculate the volume of the hole in cubic metres (using V = πr2h) and then subtract the volume of your post. This will give you the volume of concrete required. Simply multiply the volume figure by 108 (108 bags per cubic metre) to give the amount of 20kg bags needed to fill the void.
No mixing required. Simply pour in approximately 1.5 litre of clean water in the hole. Add half the contents of the bag and then tamp with a steel rod to entrain the water into the mix.
Empty the remaining half of the bag contents and add a further 0.5 litre of water. Tamp again and finally compact the surface.