"capacity of a concrete truck,the large usual sixe is 9 yards,the smaller are about 3 yards"
Actually over the years the size of mixer drums has increased
You will notice the large the drum the more axles the truck has plus it depends on what make a mixer it is 1) London 2) Jaeger 3) Rex
The early 3 axle trucks with a rex mixer carried 5 cu yards
That increased to 7 cu yards
London and Jaeger drums carried 8 cu yards
On trucks with 3 axles and a tag (4th axle that trails the truck) carried 12 yards or 10m3
The newer 5 axle trucks usually hold 14-16 cu yards
Please understand that 1 m3 = 1.3 cu yards
1 cu yard/27 cu ft of 20 mpa concrete at a 3" slump weights - 3400 lbs
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