The Significance of Grain Size Distribution for the Behaviour of High Strength Concrete for Road Purposes

In the last years high strength concrete has been used more and more frequently for road construction in Norway. To obtain good abrasion properties and a good wurkaL,ility the quality of the coorco oggrogateE and the ovrall grain qi7 ,9 distribution is very important. By improving the abrasion properties it often happens that the properties of the fresh concrete are harmed. Therefore compromises are necessary to guarantee satisfactory results. This paper presents the experiences gained from 12 road surfacing projects. Based on these analysis and on previous experiences gained from field and laboratory tests the following guidelines are proposed: requirements for the mechanical proportios of the coarse aggregates expressed in the Norwegian abrasion value (Abr), in the Norwegian friability value and in the abrasion resistance according to the formula Abr T S upper and lower limits of the grain size distribution of the sand aggregate and the overall grain size distribution (normally 0-16 mm).