No fines concrete is a kind of special concrete mixture that as the name suggests by itself, it contains little or no fine aggregate. It is produced by omitting the fine, material sand from the conventional concrete, so its main components just include coarse aggregate, cement and water. The compressive strength of no fines concrete is very low and depends on the water-cement ratio, cement content, and aggregate grades.
Adding no fine aggregates in this concrete leads to that there are voids left in the coarse aggregate, which makes the concrete lightweight and reduces its overall strength and also offers an architecturally attractive look. The course aggregates used in no fines concrete may be any of the usual type or the light weight aggregate. Very often only single sized coarse aggregate, of size passing through 20 mm retained on 10 mm is used. The single-sized coarse aggregates are surrounded and held together by a thin layer of cement paste giving strength of concrete.
No fines concrete is not suitable for reinforced concrete structure applications. However, the walls made of it can be used in cold countries due to its good thermal insulating characteristics.