Influence of Sea Sand and River Sand on the Formulation of Ordinary Concrete

Sand is one of the main constituents of concrete. Its granular skeleton enables the aggregates to be combined with cement, giving concrete greater compactness. This research evaluated the influence of sand type on the formulation parameters of ordinary concrete, specifically the dosage of each constituent, the cement/water ratio and the compressive strength. Two types of sand were chosen for this study: sea sand and river sand from Rabat (Morocco). These sands underwent characterization tests to ensure their feasibility of use in concrete. Using the Dreux Gorisse method, two formulations were studied. The first consisted of cement, water, crushed sand, sea sand and GI and GII gravel. The second uses the same constituents, but with replacement of sea sand by river sand. The characterization results confirmed that river sand is marked by its high fineness, elevated cleanliness and low water absorption capacity, illustrated respectively by a fineness modulus of 2.49%, a sand equivalence coefficient of 75% and a water absorption coefficient of 0.79%. As for sea sand, it has a considerable cleanliness and high-water absorption (1.50%). Furthermore, river sand exceeds sea sand in terms of concrete strength. This strength difference can be explained by the high cleanliness and rounded texture of river sand, which ensures excellent compactness and better cement adhesion. Also, the presence of chlorides in sea sand can reduce its strength. In summary, it appears that the sand type has an impact on the concrete formulation and on its properties in terms of density, compactness and strength.