Valorization of Fluvial Sediments Treated with Hydraulic Binders and Influence of the Particle Size Distribution of the Incorporated Correctors on Their Properties

The large quantities of dredged sediments present a significant environmental and storage challenge, particularly when contamination levels are high. This study is focused on the valorization of dredged river sediments as road materials. Sediments studied come from the Kherrata dam and the Soummam river located in Bejaia (northern Algeria). Self-compacting materials for trench backfilling and road sub-layers are the two applications targeted. The raw sediments must first be characterized. Processing aptitude tests are carried out on sediments, this allow distinguishing them based on their characteristics. The treatments were optimized following these different experiments which were carried out according requirements for use as self-compacting materials and roads sub-layers. The fluidity of the self-compacting materials is a determining criterion, the compression strength and tensile strength are two parameters to be checked before the validation of the formulas retained for the two applications. Finally, the authorization age of the traffic on the treated layer is important. In the treatment of the two sediments, two sands with different grain size were combined with binders (cement or lime). The mechanical strength of the solidified materials is influenced by the grain size distribution of the added sands. In contrast to the low resistances obtained in lime mixtures, the cement treatment, in combination with well-graded and a spread grain size distribution sand, provides adequate strength and satisfies the regulatory requirements of the two targeted fields application, especially self-compacting materials. As a result, the appropriate formulations for each application can be selected based on the findings.