Effect of Soil’s Acidity and Saturation on Degradation of Fracture Toughness of Buried Cast Iron

Abstract

There has been limited research in the past on the effect of varying soil’s acidity measured as pH and saturation measured as moisture content on the fracture toughness of buried cast iron as per comprehensive literature review. This paper presents findings obtained from a long-term test designed to investigate the combined effect of varying levels of soil’s acidity and saturation on the fracture toughness of buried cast iron over time. Relations for the change in candidature fracture toughness of the corroded cast iron over time as a function of soil’s pH, moisture content, and corrosion pit depth are developed. Moreover, a relation correlating the change in microstructure and the fracture toughness of the corroded cast iron is also developed. The significance of the current paper is that it reports that soil’s corrosivity induces a change in the microstructure and composition of cast iron, which consequently affects the fracture toughness of the corroded cast iron.