Microstructure of a compacted silt

• Published in: Canadian geotechnical journal Vol. 33; no. 1; pp. 150 - 158
• Main Authors: Delage, Pierre, Audiguier, Martine, Cui, Yu-Jun, Howat, Michael D
• Format: Journal Article
• Language: English
• Published: Ottawa, Canada NRC Research Press 25-03-1996; National Research Council of Canada
• Subjects: Applied sciences; Buildings. Public works; Exact sciences and technology; Geotechnics; Soil mechanics. Rocks mechanics; Mercury porosimetry; Clay; Grain size analysis; Scanning electron microscopy; Proctor test; Silt; Experimental study; Microstructure; Soil mechanics; Cohesive soil
• ISSN: 0008-3674; 1208-6010
• DOI: 10.1139/t96-030

This paper presents a qualitative and quantitative study of the microstructure of a compacted silt, carried out using a scanning electron microscope and mercury intrusion pore size distribution measurements. Samples have been statically compacted at three water contents: on the dry side of the standard Proctor optimum water content, at the optimum, and on the wet side. The wet sample has a matrix type structure, with a clayey fraction filling the voids and adhering to the silt-sized grains, whereas the other samples display a structure characterized by a skeleton made of silt grain aggregates linked together by clayey bidges. The distribution of water and air within the microstructure of the compacted soil is described for each of the three compaction states.
Key words: compacted soil, microstructure, scanning electron microscope, pore size distribution, mercury intrusion, clay hydration.