Title: Marine Dredged Sediments as a Partial Alternative to Sand in Cementitious Systems Using Particle Packing Optimization

Author(s): Parisa Heidari, William Wilson, and Patrice Rivard

Publication: Symposium Paper

Volume: 362

Issue:

Appears on pages(s): 639-650

Keywords: cementitious systems, environmentally friendly alternatives, marine dredged sediments, packing density optimization

DOI: 10.14359/51741018

Date: 6/14/2024

Abstract:
There is a growing concern regarding the accumulation of marine waste and the negative environmental impacts of cement-based materials. To address these issues, this study explores new possibilities for upcycling marine dredged sediments (MDS) from the Magdalen Islands in Quebec as an alternative to sand, which can be challenging to procure for islands. The characterization of these MDS showed their inert quartz nature. However, by employing packing density optimization methods, it was found that MDS can be effectively used as a partial replacement for sand. The study demonstrates that a 20% volumetric replacement of sand with MDS yields a maximum theoretical packing density of 0.796 and an experimental density of 0.747. The physical and mechanical properties of five mortar mixtures with varying volumetric ratios of MDS to sand from 0 to 50% were evaluated. The findings indicate that increasing the MDS dosage results in a slight reduction of slump flow. However, replacing 20% of the sand with MDS provides the maximum packing density and results in a 12% enhancement in 28-day compressive strength (with a slight increase in bulk electrical resistivity). These results highlight the importance of the development of closely packed granular skeletons in cementitious systems for the development of environmentally friendly alternatives to conventional cement-based materials.