A platform for research: civil engineering, architecture and urbanism
A platform for research: civil engineering, architecture and urbanism
Free swell potential of lime-treated gypseous soil
https://orcid.org/0000-0003-0776-2297
Abstract Lime treatment generally enhances the geotechnical properties of the soils. However, some studies have reported an adverse effect, especially in the presence of gypsum. To develop an understanding of the underlying mechanisms, a study of fine-grained soil with different amounts of gypsum was carried out. The influence of curing conditions (curing period and curing temperature) and wetting-drying cycles on the swell potential of fine-grained soil with (0, 5, 15 and 25%) gypsum was investigated to assess the long-term behavior of this type of soil (i.e. gypseous soil) when used in the construction of road and pavement structures. Mineralogical and microstructural studies (porosimetry, X-ray diffraction and scanning electron microscopy) were carried out to evaluate the cementitious materials and the presence of ettringite. The results show that increasing the gypsum content decreased the swell potential of the untreated soil samples. On the other hand, the swell potential values of soil samples started decreasing after the first wetting–drying cycle then reached equilibrium. Lime treatment results show that the suppression of swelling in lime-treated soil samples without gypsum was partly lost after the first cycle, especially for short curing periods and for both temperature values (20°C and 40°C), while long-term curing periods (more than 28days) gave good results with respect to the suppression of swell potential values. Lime treatment of gypsum-containing samples showed an adverse effect on swell potential. The swell potential values increased with curing period and curing temperature, due to the formation of ettringite. Lastly, wetting–drying cycles caused an increase in the swell potential values of gypsum-containing samples, cancelling out the beneficial effect of lime treatment to control swell.
Highlights Lime addition and curing conditions enhanced the swell potential of natural soil. In the presence of gypsum, swell potential is due to ettringite formation. Osmotic suction, contributed to increasing swell potential. The first wetting–drying cycle causes more distress for the gypsum soil.
Free swell potential of lime-treated gypseous soil
https://orcid.org/0000-0003-0776-2297
Abstract Lime treatment generally enhances the geotechnical properties of the soils. However, some studies have reported an adverse effect, especially in the presence of gypsum. To develop an understanding of the underlying mechanisms, a study of fine-grained soil with different amounts of gypsum was carried out. The influence of curing conditions (curing period and curing temperature) and wetting-drying cycles on the swell potential of fine-grained soil with (0, 5, 15 and 25%) gypsum was investigated to assess the long-term behavior of this type of soil (i.e. gypseous soil) when used in the construction of road and pavement structures. Mineralogical and microstructural studies (porosimetry, X-ray diffraction and scanning electron microscopy) were carried out to evaluate the cementitious materials and the presence of ettringite. The results show that increasing the gypsum content decreased the swell potential of the untreated soil samples. On the other hand, the swell potential values of soil samples started decreasing after the first wetting–drying cycle then reached equilibrium. Lime treatment results show that the suppression of swelling in lime-treated soil samples without gypsum was partly lost after the first cycle, especially for short curing periods and for both temperature values (20°C and 40°C), while long-term curing periods (more than 28days) gave good results with respect to the suppression of swell potential values. Lime treatment of gypsum-containing samples showed an adverse effect on swell potential. The swell potential values increased with curing period and curing temperature, due to the formation of ettringite. Lastly, wetting–drying cycles caused an increase in the swell potential values of gypsum-containing samples, cancelling out the beneficial effect of lime treatment to control swell.
Highlights Lime addition and curing conditions enhanced the swell potential of natural soil. In the presence of gypsum, swell potential is due to ettringite formation. Osmotic suction, contributed to increasing swell potential. The first wetting–drying cycle causes more distress for the gypsum soil.
Free swell potential of lime-treated gypseous soil
https://orcid.org/0000-0003-0776-2297
Abstract Lime treatment generally enhances the geotechnical properties of the soils. However, some studies have reported an adverse effect, especially in the presence of gypsum. To develop an understanding of the underlying mechanisms, a study of fine-grained soil with different amounts of gypsum was carried out. The influence of curing conditions (curing period and curing temperature) and wetting-drying cycles on the swell potential of fine-grained soil with (0, 5, 15 and 25%) gypsum was investigated to assess the long-term behavior of this type of soil (i.e. gypseous soil) when used in the construction of road and pavement structures. Mineralogical and microstructural studies (porosimetry, X-ray diffraction and scanning electron microscopy) were carried out to evaluate the cementitious materials and the presence of ettringite. The results show that increasing the gypsum content decreased the swell potential of the untreated soil samples. On the other hand, the swell potential values of soil samples started decreasing after the first wetting–drying cycle then reached equilibrium. Lime treatment results show that the suppression of swelling in lime-treated soil samples without gypsum was partly lost after the first cycle, especially for short curing periods and for both temperature values (20°C and 40°C), while long-term curing periods (more than 28days) gave good results with respect to the suppression of swell potential values. Lime treatment of gypsum-containing samples showed an adverse effect on swell potential. The swell potential values increased with curing period and curing temperature, due to the formation of ettringite. Lastly, wetting–drying cycles caused an increase in the swell potential values of gypsum-containing samples, cancelling out the beneficial effect of lime treatment to control swell.
Highlights Lime addition and curing conditions enhanced the swell potential of natural soil. In the presence of gypsum, swell potential is due to ettringite formation. Osmotic suction, contributed to increasing swell potential. The first wetting–drying cycle causes more distress for the gypsum soil.
Free swell potential of lime-treated gypseous soil
Aldaood, Abdulrahman (author) / Bouasker, Marwen (author) / Al-Mukhtar, Muzahim (author)
Applied Clay Science ; 102 ; 93-103
2014-10-24
11 pages
Article (Journal)
Electronic Resource
English
Free swell potential of lime-treated gypseous soil
| Online Contents | 2014
Soil–water characteristic curve of lime treated gypseous soil
| Elsevier | 2014
Mechanical Behavior of Gypseous Soil Treated with Lime
| Online Contents | 2020
Soil–water characteristic curve of lime treated gypseous soil
| Online Contents | 2014
Geotechnical properties of lime-treated gypseous soils
| Online Contents | 2014