When the amount of water in concrete increases than in returns fluidity of concrete increases. Now when the fluidity of concrete increases then as a result density of concrete decreases and when this happens than heavy aggregates settle down and lightweight aggregates moves to the upper surface of concrete and thus a non-uniform distribution of strength occurs in the cross-section of concrete
Overcome Bleeding in Concrete
Take at least that much amount of water which will be required for filling voids inside the particles.
Take an extra amount also which will be absorbed on the surface of particles.
Take also some extra amount of water that will lubricate the particles of sand, cement and aggregates.
If only that much amount of water is added to the concrete during batching then chances of segregation and bleeding will be minimized.