Influence of Suction on Mass Loss of Compacted Clayey Soil from the Guabirotuba Formation in Southern Brazil

• Published in: Geotechnical and geological engineering 2024-09, Vol.42 (7), p.6339-6361
• Main Authors: Britto, Tainá Silva Sá, Silva Costa, Weiner Gustavo, Muñoz, Yeimy Ordoñez, Patzsch, Jacqueline Cristina, da Silva, Cleyton Stresser, dos Santos Izzo, Ronaldo Luis
• Format: Article
• Language: English
• Subjects: Civil Engineering; Clay; Clay soils; Compacted soils; Density; Desaturation; Earth and Environmental Science; Earth Sciences; Embankments; Erosion resistance; Filter paper; Geotechnical Engineering & Applied Earth Sciences; Hydrogeology; Membrane permeability; Moisture content; Original Paper; Permeability; Permeability coefficient; Permeability tests; Physical characteristics; Resistance factors; Saturated soils; Saturation; Soil chemistry; Soil compaction; Soil density; Soil erosion; Soil permeability; Soil properties; Soil resistance; Soil suction; Soil water; Terrestrial Pollution; Unpaved roads; Void ratio; Waste Management/Waste Technology; Water purification
• ISSN: 0960-3182; 1573-1529
• DOI: 10.1007/s10706-024-02894-2

Compacted soils are vital in constructing unpaved roads and embankments for infrastructure projects, requiring a thorough understanding of how different soil properties influence erosion. This research examined the influence of suction on the mass loss of clayey soil from the Guabirotuba Formation, compacted at various degrees of saturation and densities. The study involved initial physical–chemical, mineralogical, and morphological soil characterization. Tests were then conducted to determine the soil water characteristic curve, hydraulic conductivity, and erodibility using the filter paper method, permeability tests, and the Inderbitzen test. Samples were compacted to dry unit weights of 14.55 kN/m 3 , 15.42 kN/m 3 , and 16.28 kN/m 3 with saturation levels of 20%, 50%, 91.08%, 93.49%, and 95.60%. Results showed that variations in soil density altered the soil water characteristic curve, tending towards a unimodal shape with reduced void ratios. Soil permeability decreased in the desaturation zone of the curve. The study determined that soil mass loss is primarily influenced by saturation degree and density, with saturation emerging as the most crucial factor. Erosion resistance was observed to be lowest at 50% saturation compared to both 20% and optimal saturation levels, which was associated with a reduction in the unsaturated permeability coefficient. It has been found that the influence of slope is negligible. Therefore, soil saturation levels significantly affect erosion resistance, making the soil more susceptible to disruption when air continuously occupies the pore space.