Effect of Heat on the Properties of Expansive Soils

Abstract

Expansive soils, known for having negative effects on construction projects, create difficulties due to their unpredictable volume fluctuations in reaction to moisture variations. The issues these soils present cannot always be solved by using conventional soil stabilizing techniques. The primary objective of this research entitled The Effect of Heat Treatment on the Properties of Expansive Soils was to examine the viability of adopting heat treatment as a novel method to improve the engineering properties of expansive soils. It aims to produce mineralogical modifications and positive physical behaviour improvements that reduce swelling and shrinking and improve load bearing property by submitting soil samples to regulated heat treatment. The employed methodology involves laboratory experiments encompassing soil sample collection, controlled heat treatment using digital thermostat furnace with temperatures ranging from 100oC to 600oC for a duration of one hour. These tests cover Free Swell, Linear Shrinkage, Sieve Analysis, Atterberg Limits, Compaction tests and CBR . Data analysis and optimization was followed to establish relationships between treatment parameters and property enhancements. The results of the study indicate that heat treatment can actually improve the engineering properties of expansive soils by decreasing plasticity and swelling properties and increasing density and CBR. In this particular study, most of the improvements were achieved at a temperature of 500oC.