Soils usually have many problems which limit their use as a construction material and as a suitable site for construction. Soils problems such as high water content, plasticity, activity, compressibility, and swelling potential and/or low permeability and strength often cause serious problems including bearing capacity failure, excessive settlement, and swelling, among other problems. As the availability of suitable construction sites decreases, it is becoming more important to utilize poor soils for foundation support and earthwork construction using different methods of soil stabilization.

The collective term for the methods which are employed to improve and modify certain unsatisfactory properties of natural soil is called soil stabilization. Methods of soil stabilization are numerous and divided mainly to mechanical, chemical, and physical methods.

Physical stabilization methods comprise several methods including electro-osmosis, consolidation, and thermal stabilization. Thermal stabilization refers to the artificial freezing and heating of soils for the purpose of improving the engineering characteristics of the ground soil. Both these processes involve the use of thermal energy, but they are quite different and opposite in their applications.

This paper concentrates on the study of the effect of thermal stbilization by heating on some clay soils. The selection of this specific method can be justified knowing that it was one of the most ancient methods used by man especially in old Egypt and Mesopotamia. Yet, it was ignored and not improved for many centuries until the last few years. Recently this method of stabilization took a momentum, Therefore, the concentration on the understanding and use of heating as an excellent soil stabilization method has increased drastically.

This paper is devoted to reveal the results of an experimental study that was carried out on two types of clays; Kaolin and Bentonite. These clays were heated gradually up to 600⁰c, and the effect of heating on swelling, compressibility, and strength of these clays were investigated.

The results showed that heating kaolin to a temperature of up to 300^oC caused the elimination of its free and adsorbed water. Heating to a higher temperature of 400^oC reduced its swelling and compressibi9lity, while heating to 500^oC resulted in increasing its strength. On the other hand, heating bentonite to 300^oC resulted in the elimination of its free and adsorbed water, while heating to 600^oC changed it to a nonexpansive state, reduced its compressibilitym and increased its strength. These changes were irreversable.

Keywords: Soil improvement, clay soil stabilization, thermal soil stabilization, clay soil heating, kaolinite, bentonite

Conference Title

2nd Internatiwwonal Conference on Civil Engineering-Palestine

Conference Country

Palestine

Conference Date

Nov. 25, 2019 - Nov. 26, 2019

Conference Sponsor

Engineers Association- Jerusalem Center

Additional Info

Conference Website