Mechanical and thermo-physical characterization of mortars made with uncontaminated marine sediments

In a context of sustainable development, civil engineering must increasingly use recyclable materials to preserve natural resources. Sediments could be a solution in the context of their recovery in several areas. Uncontaminated marine sediments were used to partially substitute sand aggregate in the formulation of mortars. Five mortars were manufactured with different percentages of sand substitution. Physical, chemical, mineralogy, and mechanical characterization were carried out in order to investigate their possible use and impact in cemented-based materials. The mechanical strengths and the elastic modulus of mortars were analyzed. The hydration kinetics of the mortars were studied at different temperatures. The acceleration of the chemical reactions was also assessed through the determination of the apparent activation energy of mortars. Finally, the microstructure of two formulations of mortars was observed by Scanning Electron Microscope (SEM). Results show a drop of the mechanical properties with the increase of the percentage of substitution. This can be attributed to the natural composition of sediments and to the increase of the total porosity of the mixtures. The measured heat released of mortars increase with the increase of sediment content. This result suggests an additional chemical activity linked to the presence of sediments within the matrix.

Automated summary

In the context of sustainable development, civil engineering is increasingly using recyclable materials to preserve natural resources. This study explores the use of uncontaminated marine sediments as a partial substitute for sand aggregate in mortars. The results show a decrease in mechanical properties with an increase in sediment content, indicating a potential impact on the performance of cement-based materials.