Characterisation of compacted road sandcretes: Study applied to Senegal

The import of bituminous binders to Senegal is putting a strain on the balance of trade which is already in deficit. It is therefore essential to find substitutes for these materials. The use of concretes made from fine aggregates exclusively is an alternative to materials using bituminous binders; this type of concrete can be made using local materials, naturally occuring sands from dunes and residual sands from the crushing process. Studies have been carried out on four compacted concretes made from fine aggregates exclusively using 0-3 mm filled sands produced from the crushing of limestone, sandstone, cherts and basalts. The physical characteristics and mechanical performance of these materials are very encouraging for justifying the choice of sandcrete in road construction. A comparison with flexible pavements has shown that an economic advantage varying between 54% and 110% can be obtained, depending on the type of addition and the road classification.Original Abstract: En substitution aux materiaux hydrocarbones dont l'importation greve la balance commerciale deja deficitaire au Senegal, les betons de sable peuvent etre une alternative de taille n'utilisant que des materiaux locaux, excedentaires (sable des dunes) et residuels (sables fillerises de concassage). Les etudes ont porte sur quatre betons de sable compactes utilisant comme ajouts, des sables fillerises 0/3, residus de concassage de calcaire, de gres, de silexite et de basalte. Les caracteristiques physiques et les performances mecaniques des betons confectionnes sont largement rassurantes pour justifier le choix des betons de sable compactes en structures de chaussees. En effet, en comparaison avec des chaussees souples, des economies financieres variant entre 54% et 110% peuvent etre realisees suivant le type d'ajout et la classe de trafic consideres.