Optimization and valorization of a clay and dune sand mixture for use in road construction

Abstract

Road construction plays an important role in the development of a country like Morocco. Most of the expansive soils found in the country are clay or marl, which have a "normal" state that is dry and dense. The problems created by these soils in the construction field are primarily due to soil swelling. For this reason, we have chosen to focus our work on the swelling behavior of clayey soils and evaluate the influence of adding dune sand in geotechnical studies to stabilize and modify the physico-chemical and mechanical characteristics at different percentages, considering oedometer tests.The treated and untreated soil samples are compacted at the optimum Proctor (WOpt and γDmax). The results of the compressibility tests show that the preconsolidation stress and consolidation of the treated samples are higher than those of the untreated samples. It has also been observed that dune sand reduces the compressibility index (Cc) and swelling index (Cg). Therefore, it can be said that stabilization with dune sand significantly improves the mechanical characteristics of the studied clay.The utilization of the studied materials presents a clean and cost-effective alternative in the field of road construction.