Abstract
While traditional methods of soil stabilization using cement or lime have been extensively researched, there is a notable gap in understanding the mechanical behavior of soil stabilized with innovative materials. This study aims to investigate the mechanical properties of soil stabilized with polyurethane (PU) foam, nanosilica, and basalt fiber. Unconfined compressive strength (UCS) and direct shear tests were conducted on reconstituted silica and calcareous samples treated with various combinations of these additives. Various parameters, including additive content, curing time, and freeze–thaw cycles, were thoroughly examined. The findings demonstrate a significant increase in UCS and shear strength parameters (c and ϕ) with the addition of PU foam, nanosilica, or their combination with fiber. Notably, the combination of PU and basalt fiber exhibits the most promising performance in improving the mechanical behavior and freeze–thaw durability of silica and calcareous sand, especially for short curing times. Additionally, calcareous samples consistently exhibit higher UCS, and shear strength compared to silica samples. Furthermore, the analysis of failure patterns and the microstructure of the samples using scanning electron microscopy provides insights into the effectiveness of these stabilizing agents and their influence on the mechanical properties of the soil.
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Shahidi, S., Bayat, M. & Zareei, S.A. Enhancing Mechanical Behavior of Silica and Calcareous Sand through Polyurethane Foam, Nanomaterial, and Fiber. Indian Geotech J (2024). https://doi.org/10.1007/s40098-024-00971-0
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DOI: https://doi.org/10.1007/s40098-024-00971-0