STUDYING THE EFFECT OF THE ADDITIONS ON EXPANSIVE SOILS

Abstract

Expansive soils cause damages to civil engineering structures in various parts of the world, because they swell when absorb water and shrink when they dry out. Additional stresses applied to the structures due to the swell pressures are important in explaining some of the damages to the structures in expansive soils. Therefore the prediction of the swell pressures and taking them into consideration in the design of structures is needed. In this study, the relationship between the index properties and swelling characteristic of expansive soils is examined. The earlier studies showed that an increase in dry density and plasticity index of the soil cause an increase in swell pressure, while a decrease in natural moisture content cause an increase in swell pressure. In this paper, ALmarj soil will be used because of their properties to compare the swelling before and after adding the additions, that will be:- 1. Fine aggregate 2. Burned oil. These additions are choosing because they are cheap and recyclable available materials. The experimental study results show that, the soil properties after adding these additions have been changed with different ratio.