In Wet Fine aggregate 30% bulkage will occure . Concrete cube will be casted correctly by 150mm height
Ex M20 1:1.5:3
27% of fine aggregate in 150mm cube
27%wet volume include 8%(i.e., 30%bulkage of its dry volume)
After setting this 8% will reduce.
So 150mm cube la 8% reduction occure. But cube size doesn't reduce. Why?
I did not understood your question, yet will try to answer with basics.
Bulkage is false increase in volume due to adsorb water on surface of sand.
Today no one do concrete by doing volume batching.
For academics, you can calculate the bulkage and accordingle adjust the volume of sand to be taken for doing concrete.
Bulkage is term for perticular material i.e. - sand.
When it is mixed with other ingredients of concrete and the saturation level is reached which nullify the false increase volume of sand.
This is the reason even though we do not account for bulkage, it wont affect on volume of concrete poured location.
Where bulkage do affect.
In volume of mixed concrete, it make reduction due to bulkage. Say you made 1 cum but actual volume may be 0.9 cum or anything else depends bulkage in sand.
Now say from this 0.9 cum, you made a cube - cube will not shrink as the effect of bulkage had gone after mixing all ingredient.
Bulkage affects - workability, strength and durability etc.
Also it affect your cost of project due to wasting money on paying for false volume.
