Volume reduction happens immediately after the concrete is mixed. The volume reduction will generate stress when the concrete has achieved its final setting time because stress is not generated before the concrete has gained some strength. Autogenous shrinkage is therefore defined as the shrinkage that is measurable after the final setting time of the concrete.
at present days many kinds of advanced concrete are designed to have lower water-to-binder ratio and sometimes with large paste volume.
Those examples are high strength concrete and self-compacting concrete. When compared with normal concrete, those types of concrete have smaller, lower amount of and less continuous capillary voids, or in other words, have low permeability.