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working out quantity of concrete
Posted: Fri Jun 01, 2007 10:36 pm
by joey
hi i wanted to know how to work out quantity of concrete i know volume is LxWxD but want to know how to converte this to the amount in tonnes ? thanks
Posted: Sun Jun 03, 2007 3:00 am
by joey
bump
Posted: Sun Jun 03, 2007 3:09 am
by TomVan
A 4" pour is basically 75 square feet per yard
Re: working out quantity of concrete
Posted: Sun Jun 03, 2007 4:26 am
by rod gervais
joey wrote:hi i wanted to know how to work out quantity of concrete i know volume is LxWxD but want to know how to converte this to the amount in tonnes ? thanks
OK - 27cf = 1 c yard - and 1cy = 4050# of stone concrete.
1 cu meter is 0.764554861 of 1 cy - thus 1 cm is 3096 # -
Now - a short US ton is 2000# and a Tonne is 1.102311311 US short tons - so if we work this out as follows:
1cm = 3096# (us) - which is 1.548 US tons - which is then 1.706 tonnes/
So 1 cm of concrete is 1.706 tonnes.
Rod
Posted: Sun Jun 03, 2007 7:10 am
by joey
so i have a total of 80ft x 1.75ft x 1.75ft =245ft3
245ft3 / 27 = 9 cubic yards.
so if i was to mix all in sand and ballast 850kg bulk bags and cement in a ratio of 4 to 1 how much ballast cement and water would i need ?
sorry to be a pain.
Posted: Sun Jun 03, 2007 9:18 am
by rod gervais
joey wrote:so i have a total of 80ft x 1.75ft x 1.75ft =245ft3
245ft3 / 27 = 9 cubic yards.
so if i was to mix all in sand and ballast 850kg bulk bags and cement in a ratio of 4 to 1 how much ballast cement and water would i need ?
sorry to be a pain.
Joey,
Please explain "ballast" - I am not familiar with the term.
Rod
Posted: Sun Jun 03, 2007 9:48 am
by TomVan
Please explain "ballast" - I am not familiar with the term.
aggregate
Joey,
Are you thinking of mixing 9 yards yourself? Thats quite a bit to do by yourself or with the help of friends. You might consider getting a pre mix truck delivered.
Sounds like your trying to make a design mix for cement/sand /aggregate ratios?
1 x Cement
2 x Fine Aggregate (Sand)
4 x Coarse Aggregate (Gravel/Rocks/Ballast)
If all these are dry, a water to cement ratio of around 0.55 is required. So therefore if you use 25kg of cement that will equal 13.75 litres of water. However, frequently parts of your mix like the sand will be damp, and so you will have to carefully modify your mix so that it is not sloppy.
Tom
Posted: Sun Jun 03, 2007 7:36 pm
by joey
ballast is the term used in the uk for stone etc. bulk bag = 1 ton but not less than 850kg mixed ballast which is the stone with the sand in the correct ratio to mix concrete. for example if you had 4 tons of mixed ballast and a ton of cement that would give you 5 tons of concrete excluding the water.