Improvement of the mechanical performance of dune sand for using in flexible pavements

Abstract

Roads and highways stand for important parts of the construction sector, where the excessive use of natural products has become serious threat to the economy and the environment. This is why nowadays researches focus on both the use of local materials and the improvements of the mechanical behavior of such materials. The purpose of this work is the study of dune sand which is found in abundance in the region of Djelfa (Algeria) for possible use in pavement foundations. Some mixtures of sand and hydraulic binders (cement, pozzolan + lime) were investigated in order to improve their mechanical characteristics. The prepared mixtures were subjected to classification tests, tests of grain size distributions, tests of compaction with modified Proctor, shear strength, tests of bearing pressure (CBR unsoaked and soaked), compressive and tensile strength. The obtained results have shown that some mixtures are of high mechanical characteristics and could be then used in layers of pavement foundations.