Behavioral analysis and structural evolution of bothkennar clay: Insights from laboratory and field investigations

Bothkennar clay is a type of soft clay found near the Firth of Forth in Scotland, at the Bothkennar site, which was established in the late 1980s as a national research center for advanced studies on soft clays. This paper analyzes the behavior of Bothkennar clay under both natural and remolded conditions, drawing on data from laboratory and field experiments. Special attention is given to the results of triaxial tests and oedometer tests, which are crucial for understanding the stress-strain response under different stress paths. The analysis largely employs the Cam-clay model, a widely used constitutive model in geotechnical engineering, to investigate the clays behavior during loading and unloading. Additionally, this study explores the clays internal structure, focusing on plastic anisotropy and destructuration, which reflect changes in the clay's behavior over time. A sensitivity framework and a normalization framework are also applied to better understand the deformation mechanisms and structural evolution of the clay. These studies not only shed light on the clays natural characteristics but also provide critical insights for model calibration and foundation stability predictions. As a benchmark material in soil mechanics, Bothkennar clay plays a key role in validating theoretical models and advancing research on the behavior of soft clays in geotechnical engineering.