Exploratory of the freezing-thawing behavior of clay and steel slag mixtures

Abstract

Stabilization of clayey soil has been studied by mixing different additives to the soil to increase its strength and durability. Recently, there has been an increasing interest in the stabilization of soils with natural pozzolans. Nevertheless, very few articles have investigated the impact of basic oxygen furnace (BOF) slag additives under freeze-thaw cycling. This study presents the results of an experimental research study on the durability behavior of clayey soils treated with BOF slag. In this study, the effects of clay soils on the bearing value were investigated by adding 3%, 6%, 9%, 12%, 15%, and 20% BOF slag to the clay mineral sample within the scope of ASTM D-5918 tests. California bearing ratio (CBR) tests were then applied before and after freezing-thawing processes to the samples prepared at these optimum conditions. The relationship between the determined freezing and swelling speeds and the strength losses of the soil samples after freeze-thawing processes were investigated. For this purpose, eight mixtures with different geotechnical properties were subjected to freeze-thaw experiments on a total of 24 soil samples, each of which was repeated three times. Results show that the addition of steel-making slag to clay soils lead to favorable effects on freezing-thawing behavior. The effects of BOF slag on the clay sample after the freezing and thawing cycle were investigated and interpreted by considering their macro and micro phase structure. The findings indicate that using BOF slag has positive effects on strength and durability of clayey soil.