<abstract xmlns="http://www.w3.org/1999/xhtml"><p>The objective of this research was to investigate the effect of adding thermally treated clay on some engineering properties of the untreated expansive clayey soil. Three expansive clayey soil samples obtained from three different sites in the south of Syria have been investigated. They were thermally treated up to three different levels (450°C, 650°C and 850°C) for 3 hours. Three replacement levels of thermally treated clay were used, i.e. 0%, 10% and 20%. The X-ray diffractometer (XRD) technique has been used to detect the crystalline and glassy phase in the clayey samples before and after the thermal treatment. Pozzolanic activity of the thermally treated clayey soil has been studied using the modified Chapelle test and the mechanical strength test at each of the temperature levels. Atterberg limits, compaction, free swell, swelling pressure and linear shrinkage have particularly been investigated. Test results revealed the positive effect of thermally treated clay when added to the natural soil. Plasticity index (PI) was reduced by about 60% when 20% thermally treated clay was added to the natural soil. In addition, 6% lime was added to further investigate the combined effect of lime and calcined clay on the properties of the clayey expansive soil. All investigated properties were significantly improved when 20% thermally treated soil and 6% lime were added together. For instance, swelling pressure and linear shrinkage values were reduced to less than 15% or even much less when compared with those of the natural soil. Scanning electron microscopy (SEM) and energy-dispersive X-ray (EDX) analysis were employed as well.</p></abstract>

The objective of this research was to investigate the effect of adding thermally treated clay on some engineering properties of the untreated expansive clayey soil. Three expansive clayey soil samples obtained from three different sites in the south of Syria have been investigated. They were thermally treated up to three different levels (450°C, 650°C and 850°C) for 3 hours. Three replacement levels of thermally treated clay were used, i.e. 0%, 10% and 20%. The X-ray diffractometer (XRD) technique has been used to detect the crystalline and glassy phase in the clayey samples before and after the thermal treatment. Pozzolanic activity of the thermally treated clayey soil has been studied using the modified Chapelle test and the mechanical strength test at each of the temperature levels. Atterberg limits, compaction, free swell, swelling pressure and linear shrinkage have particularly been investigated. Test results revealed the positive effect of thermally treated clay when added to the natural soil. Plasticity index (PI) was reduced by about 60% when 20% thermally treated clay was added to the natural soil. In addition, 6% lime was added to further investigate the combined effect of lime and calcined clay on the properties of the clayey expansive soil. All investigated properties were significantly improved when 20% thermally treated soil and 6% lime were added together. For instance, swelling pressure and linear shrinkage values were reduced to less than 15% or even much less when compared with those of the natural soil. Scanning electron microscopy (SEM) and energy-dispersive X-ray (EDX) analysis were employed as well.

Thermally Treated Clay as a Stabilizing Agent for Expansive Clayey Soil: Some Engineering Properties

Studia Geotechnica et Mechanica

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

The objective of this research was to investigate the effect of adding thermally treated clay on some engineering properties of the untreated expansive clayey...

Thermally Treated Clay as a Stabilizing Agent for Expansive Clayey Soil: Some Engineering Properties

Article Category: Research Article

Published Online: Nov 22, 2018

Page range: 220 - 232

Received: Jul 23, 2018

Accepted: Oct 04, 2018

DOI: https://doi.org/10.2478/sgem-2018-0025

Keywords
thermally treated clay, soil improvement, plasticity index, linear shrinkage

© 2018 Aref M. Al-Swaidani et al., published by Sciendo

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

Thermally Treated Clay as a Stabilizing Agent for Expansive Clayey Soil: Some Engineering Properties

Article Category: Research Article

Published Online: Nov 22, 2018

Page range: 220 - 232

Received: Jul 23, 2018

Accepted: Oct 04, 2018

DOI: https://doi.org/10.2478/sgem-2018-0025

Keywordsthermally treated clay, soil improvement, plasticity index, linear shrinkage

© 2018 Aref M. Al-Swaidani et al., published by Sciendo

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

Keywords
thermally treated clay, soil improvement, plasticity index, linear shrinkage