Bayesian identification of soil strata in London clay

Identification of soil strata in the London Clay Formation (LCF) is of practical significance as it allows geotechnical property data within the same soil strata to be compared or used effectively. The soil strata in LCF are generally determined based on their lithological characters and fossil contents, with which geotechnical engineers are less familiar. To assist geotechnical engineers in identifying the soil strata in LCF, this paper aims to develop Bayesian approaches to identification of soil strata in LCF using water content data. Equations are derived for the proposed Bayesian approaches, and the approaches are illustrated using a water content profile at St James's Park, London. The proposed Bayesian approaches are shown to correctly identify the soil strata in LCF. In addition, a sensitivity study is performed to explore the effect of data quantity (i.e. both the measurement interval and number of measurements at the same depth) in a water content profile and provide guidance on the water content measurements during site investigation for optimising usage of the proposed Bayesian approaches.