A Review Study of Techniques and Use of Thermal Stabilization of Soil

Abstract

The process of stabilization is performed at a large scale by using various procedures to improve and modify soil properties. Searching a good method for stabilization is really a big deal of concern till date. Thermal stabilization is one of an important method among the various methods of soil stabilization. Therefore, exploring thermal stabilization may result utilization of soil profitably. When the temperature is elevated, the moisture content and other volatile substances starts decreasing. This results in transfer of heat to the soil minerals, due to which soil behaviour is changed.

Furthermore to re-check this result and to treat the fine-grained soil, we have reviewed papers written by different researchers, some are as follows:

1. de Folly d’Auris et al. (2016) carried out the study on Thermal technologies applications for soil remediation.

Cang Tonga et al. (2017) studied on the implementation of the solar-ground coupled heat pump with seasonal storage system (SGCHPSS).

Charles K. Kabubo et al. (2017) carried out the study on the Effect of Heat on the Properties of Expansive Clay Soil.

Habibaafrin et al. (2017) studied Soil Stabilization, a process of improving shear strength with an increment in bearing capacity of soil.

I.M. Litvinov et al. used the thermal method of consolidation for eliminating the settling properties of loess sand to a depth of 10 to 15 m below the footing base, which resulted increase in load  bearing capacity of these soils.

Julia E. Vidonish et al. (2016) the principal environmental consequences of a variety of common thermal treatment procedures for hydrocarbon-contaminated soils were investigated and proposed frameworks for sustainable and lowimpact deployment based on a comprehensive examination of soil science, ecosystem ecology, and energy and water requirements.

Lanhua Dai et al. (2014) Heating of a solar aided ground source heat pump system (SAGSHPS) was investigated under various heating operating modes. Experimental performance analysis was used to look at the properties of the SAGSHPS.

Majed M. Abu-Zreig et al. (2001) studied on the behavior of clayey soils by influence of heat treatment.

Yan Gao et al. (2020) in China researched on Developing and rising Heat Storage of a Solar- Assisted geothermal heat pump.

Zihms S.G. et al. (2013) discussed the impact of high temperatures on soil engineering properties.

Thus we believe that thermal conductivity decreases as the moisture content decrease which leads to formation of dry zone. This dry zone creates an insulating blanket which further inhibits the dissipation of heat from the source and this makes the soil properties to be changed.

As a result, it is technically possible to use heat to stabilise fine-grained soils. The temperature, as well as any potential changes in soil qualities, are given in the following statement. 

• At 100°C, heating causes a large increase in clay strength, resulting in a decrease in soil compressibility.
• At 500 C° structure of clay changes permanently causing decrement in plasticity as well as moisture absorption capacity.
• Clay particles fuse at 1000 C° resulting in solid particles like Brick

As a result of heating the soil, it will undergo irreversible changes, making it more robust and harder. As a result, treatment would have an overall negative impact. 

• Compressibility Declines
• Cohesiveness Rises
• Internal friction angle and modulus of elasticity rise.

It is taken under note that by heating treatment given to soil increases its strength. The increase in strength in fine-grained soil is owing to a modest rise in temperature produced by a reduction in electrostatic repulsion between the soil particles. We also observed pore water movement due to changes in thermal gradient and evaporation rate, which resulted in a decrease in moisture content. Therefore, it is observed that to stabilize the fine-grained soil is technically feasible by heating.

The paper’s objective is to review the different thermal stabilization techniques based on previous experimental studies. The point of attention is, comparison of thermal stabilization with other method.