Experimental Investigation of the Soil-Water Characteristic Curves (SWCC) of Expansive Soil: Effects of Sand Content, Initial Saturation, and Initial Dry Unit Weight
Soil-water characteristic curve (SWCC) is an essential parameter in unsaturated soil mechanics, and it plays a significant role in geotechnical engineering to enhance theoretical analysis and numerical calculations. This study investigated the effects of key factors, such as the percentage of sand,...
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MDPI AG
2024-02-01
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| author | Ammar Alnmr Mounzer Omran Alzawi Richard Ray Safwan Abdullah Jihad Ibraheem |
| author_facet | Ammar Alnmr Mounzer Omran Alzawi Richard Ray Safwan Abdullah Jihad Ibraheem |
| author_sort | Ammar Alnmr |
| collection | DOAJ |
| description | Soil-water characteristic curve (SWCC) is an essential parameter in unsaturated soil mechanics, and it plays a significant role in geotechnical engineering to enhance theoretical analysis and numerical calculations. This study investigated the effects of key factors, such as the percentage of sand, initial degree of saturation, and initial dry unit weight, on the SWCC of expansive soil by measuring the matric suction using a pressure apparatus method. The empirical equation of SWCC was obtained using the Van Genuchten and Fredlung Xing models, and the processing of experimental data checks the fitting of the two empirical models. The findings revealed that the Fredlung Xing model fit the relationship between matric suction and volumetric water content of expansive soil better than the Van Genuchten model, indicating that the pressure apparatus approach’s experimental data are correct and acceptable. The study also found that the matric suction increased with decreasing percentage of added sand at the same volumetric moisture content, and the increase in initial dry unit weight increased the matric suction, with the water retention capacity decreasing significantly after adding 20% sand. Moreover, as the initial degree of saturation increased, the volumetric water content decreased, and the characteristic curves became identical when the initial saturation degree reached 90%. Finally, to minimize the water retention capacity of expansive soils, the study recommended adding a percentage of sand not less than 30% to the expansive clay sample. |
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| institution | Directory Open Access Journal |
| issn | 2073-4441 |
| language | English |
| last_indexed | 2024-04-25T00:19:18Z |
| publishDate | 2024-02-01 |
| publisher | MDPI AG |
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| series | Water |
| spelling | doaj.art-b05cd8f9ceaf41e890c294cb8d0bab0d2024-03-12T16:57:29ZengMDPI AGWater2073-44412024-02-0116562710.3390/w16050627Experimental Investigation of the Soil-Water Characteristic Curves (SWCC) of Expansive Soil: Effects of Sand Content, Initial Saturation, and Initial Dry Unit WeightAmmar Alnmr0Mounzer Omran Alzawi1Richard Ray2Safwan Abdullah3Jihad Ibraheem4Department of Structural and Geotechnical Engineering, Széchenyi István University, Egyetem Ter 1, 9026 Győr, HungaryDepartment of Geotechnical Engineering, Tishreen University, Latakia P.O. Box 2230, SyriaDepartment of Structural and Geotechnical Engineering, Széchenyi István University, Egyetem Ter 1, 9026 Győr, HungaryDepartment of Geotechnical Engineering, Tishreen University, Latakia P.O. Box 2230, SyriaDepartment of Water and Soil Science, Tishreen University, Lattakia P.O. Box 2230, SyriaSoil-water characteristic curve (SWCC) is an essential parameter in unsaturated soil mechanics, and it plays a significant role in geotechnical engineering to enhance theoretical analysis and numerical calculations. This study investigated the effects of key factors, such as the percentage of sand, initial degree of saturation, and initial dry unit weight, on the SWCC of expansive soil by measuring the matric suction using a pressure apparatus method. The empirical equation of SWCC was obtained using the Van Genuchten and Fredlung Xing models, and the processing of experimental data checks the fitting of the two empirical models. The findings revealed that the Fredlung Xing model fit the relationship between matric suction and volumetric water content of expansive soil better than the Van Genuchten model, indicating that the pressure apparatus approach’s experimental data are correct and acceptable. The study also found that the matric suction increased with decreasing percentage of added sand at the same volumetric moisture content, and the increase in initial dry unit weight increased the matric suction, with the water retention capacity decreasing significantly after adding 20% sand. Moreover, as the initial degree of saturation increased, the volumetric water content decreased, and the characteristic curves became identical when the initial saturation degree reached 90%. Finally, to minimize the water retention capacity of expansive soils, the study recommended adding a percentage of sand not less than 30% to the expansive clay sample.https://www.mdpi.com/2073-4441/16/5/627soil-water characteristic curve (SWCC)unsaturated soilsuctionvolumetric water contentexpansive soilssand |
| spellingShingle | Ammar Alnmr Mounzer Omran Alzawi Richard Ray Safwan Abdullah Jihad Ibraheem Experimental Investigation of the Soil-Water Characteristic Curves (SWCC) of Expansive Soil: Effects of Sand Content, Initial Saturation, and Initial Dry Unit Weight Water soil-water characteristic curve (SWCC) unsaturated soil suction volumetric water content expansive soils sand |
| title | Experimental Investigation of the Soil-Water Characteristic Curves (SWCC) of Expansive Soil: Effects of Sand Content, Initial Saturation, and Initial Dry Unit Weight |
| title_full | Experimental Investigation of the Soil-Water Characteristic Curves (SWCC) of Expansive Soil: Effects of Sand Content, Initial Saturation, and Initial Dry Unit Weight |
| title_fullStr | Experimental Investigation of the Soil-Water Characteristic Curves (SWCC) of Expansive Soil: Effects of Sand Content, Initial Saturation, and Initial Dry Unit Weight |
| title_full_unstemmed | Experimental Investigation of the Soil-Water Characteristic Curves (SWCC) of Expansive Soil: Effects of Sand Content, Initial Saturation, and Initial Dry Unit Weight |
| title_short | Experimental Investigation of the Soil-Water Characteristic Curves (SWCC) of Expansive Soil: Effects of Sand Content, Initial Saturation, and Initial Dry Unit Weight |
| title_sort | experimental investigation of the soil water characteristic curves swcc of expansive soil effects of sand content initial saturation and initial dry unit weight |
| topic | soil-water characteristic curve (SWCC) unsaturated soil suction volumetric water content expansive soils sand |
| url | https://www.mdpi.com/2073-4441/16/5/627 |
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