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Fine-grained soils exhibit highly complex hydro-mechanical behaviour, largely controlled by their pore structure and its evolution under environmental loading. Chemical alteration and wetting–drying cycles are key processes that affect the microstructure of clay and silt, influencing permeability, compressibility, strength, and hydraulic hysteresis. Previous studies have demonstrated that chemical interactions can induce particle aggregation or dispersion, alter diffuse double-layer thickness, and modify pore throat geometry (Delage et al., 2006). When combined with cyclic wetting–drying, these mechanisms may lead to irreversible microstructural rearrangements, which are not adequately captured by traditional void ratio-based descriptions (Romero & Simms, 2008).
Despite extensive research, conventional constitutive models generally describe these effects through empirical parameters, without explicitly representing the pore-scale mechanisms that govern soil response(Alonso et al., 1990). Advances in high-resolution pore-scale characterization, including image-based analysis and pore network modelling, have enabled quantitative assessment of pore size distribution, coordination number, throat constriction, tortuosity, and connectivity metrics (Blunt et al., 2013). Wetting–drying cycles are increasingly recognized as path-dependent phenomena, where pore evolution is influenced by both the current moisture state and the chemical and hydraulic history of the soil. Studies have systematically identified mechanisms such as irreversible pore collapse, snap-off-induced fluid trapping, chemically induced swelling or dispersion, and progressive connectivity degradation (Or & Tuller, 1999; Wildenschild & Sheppard, 2013).
This study aims to investigate the evolution of pore structure in fine-grained soils under chemical alteration and cyclic wetting–drying. It examines how pore fluid chemistry and moisture fluctuations influence pore topology, connectivity, and flow pathways. SEM images of soils with varying water content and ethyl alcohol provide initial insights into pore stabilization and changes in stiffness. The findings will support the development of pore-structure-informed constitutive models that capture hysteresis, path dependency, and environmental loading effects in geotechnical and geo-environmental applications.
| References | Alonso, E. E., Gens, A., & Josa, A. (1990). A constitutive model for partially saturated soils. Géotechnique, 40(3), 405-430. https://doi.org/10.1680/geot.1990.40.3.405 Blunt, M. J., Bijeljic, B., Dong, H., Gharbi, O., Iglauer, S., Mostaghimi, Paluszny, A., & Pentland, C. (2013). Pore-scale imaging and modelling. Advances in Water Resources, 51, 197-216. https://doi.org/10.1016/j.advwatres.2012.03.003 Delage, P., Marcial, D., Cui, Y. J., & Ruiz, X. (2006). Ageing effects in a compacted bentonite: a microstructure approach. Géotechnique, 56(5), 291-304. https://doi.org/10.1680/geot.2006.56.5.291 Or, D., & Tuller, M. (1999). Liquid retention and interfacial area in variably saturated porous media: Upscaling from single‐pore to sample‐scale model. Water Resources Research, 35(12), 3591-3605. https://doi.org/10.1029/1999WR900262 Romero, E., & Simms, P. H. (2008). Microstructure investigation in unsaturated soils: a review with special attention to the contribution of mercury intrusion porosimetry and en |
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| Country | India |
| Green Housing & Porous Media Focused Abstracts | This abstract is related to Green Housing |
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