Influence of interfacial transition zone at aggregate surface caused by bleeding on permeability

Bleeding occurs due to the different density of concrete materials. The internal bleeding water is a part of the bleeding water restrained on the lower surface of the aggregate. By creating porous zone after concrete hardening, it becomes a penetration path of deterioration factors, which leads to a decrease in the durability of concrete. In this research, the purpose is to clear the influence of changes in the aggregate interface in concrete accompanying bleeding on permeability. Concrete with different amount of bleeding was prepared and air permeability test was carried out. Furthermore, air permeability test was performed the pore existing on the lower surface of the aggregate, which was made by internal bleeding water. As a result, the air permeability increased in the tests penetration through the pore on the lower surface of the aggregate.