The chemical analysis of soils for identification of dispersivity

Abstract

The dispersivity of clay soils in water and its influence on the stability of engineered structures has been a topic of serious concern in civil projects for many years. One of the main problems is the difficulty in positively identifying such soils and thereby reducing the potential for failure of the structures. Although a number of identification methods have been proposed, no single method has proved to be entirely successful. This paper concentrates on the chemical analyses of the samples, which are generally carried out by research or commercial laboratories, usually specialising in agricultural testing, and on the discrepancies in results obtained from different laboratories, often using different test methods, as well as on the variations in the interpretation of the results. These variations can lead to conflicting conclusions resulting in inconsistent identification of potentially dispersive soils.