Today, we managed to fill a further 31 hollow columns in our retaining back
wall. This is 8 bags of cement, mixing each bag with 6 builders bucket of
ballast.
We found that putting in slightly more water in the mix, helps with the
pouring the concrete down into the hole and the vibrator thingy is very good
at knocking down the mixture. Very glad to have bought one off the web!
We found that putting the water in first and 1 bucket of ballast, mixed up
before then adding the bag of cement. This creates a very wet and slurry
mixture to help distribute throughout the further 5 buckets we then put in
all at once and while the machine is stopped. Cannot add them while it is
going because the slurry will get pushed out of the drum!! We are using
about 12litres of water to bring up the resultant concrete to a good
“flowing” consistency.
So in summary, the concrete we are making is:
1 bag of cement
12 litres of water
6 large builders bucket (3 gallon / 13.5 litre capacity) of a mixture of
small stones crushed up to pea sized (10mm) and sharp sand.