the strength of concrete is effected by water /cement ratio
as the water/cement ratio increases the strength of the concrete decreases
The water/concrete ratio, not mixing it well enough, quality of raw materials, the age of the concrete, and the temperature and humidity of the area surrounding the concrete.
Ken W. Day has written: 'Concrete mix design, quality control and specification' -- subject(s): Concrete, Quality control, Mixing, Specifications
It is typically measures in cubic yards. Anything over 2 cubic yards is a lot of mixing, so you'd likely want to order that from a concrete company in a ready mix concrete truck.
mortar are mixing by sand & cement and concrete is mixing by cement, sand & stone
no
exceed mixing and compacting
1:2:4
From 1:4 (one bag cement to 4 bag sand) to 1:6
1:4:8
exceed mixing and compacting
Small stones for mixing in concrete.
by mixing a nano-sized additive with cement.