VALORISATION OF FINE DUNE SAND IN ASPHALT CONCRETE

The south region of Algeria is characterized by a wide surface, a scattered population and a very small ratio of road length per habitant. To allow the development of agricultural, industrial and touristic activities between different cities in the south of Algeria, it is necessary to maintain and to develop the road infrastructure. However the development of these infrastructures necessitates the use of huge amount of certified aggregates from quarries which is not available in the vicinity of the need. For these raisons, in the framework of sustainable development, a strategy which consists in using local materials like fine sediments (dune sand) and other types of material is engaged. In this paper the main concern is about the development of a material including fine dune sand for wearing layer in the road construction. The semi grained bituminous concrete BBSG intended for wearing layers, known by the name BB 0/14, generally is prepared by mixing two components: aggregates and bitumen. The design of this material considers several criteria related to one hand to the aggregates, namely mechanical characteristics, shape, and cleanliness of stones, the blue value of the fine, the particle size of the mixture (% passing through), the choice of the bitumen grade and mechanical performance as well the water resistance of asphalt concrete 0/14. The present work aims to study the influence of the substitution of the fraction 0/3 mm of the crushed sand (usually used in this type of materials) by fine dune sand, on the mechanical performance including Duriez and Marshall Stability and water resistance.