Probabilistic Stratification Modeling in Geotechnical Site Characterization

Abstract

Stratification in geologic profiles is one of the most significant uncertainties in geotechnical site characterization. In this paper, a three-level probabilistic framework is proposed for geotechnical stratification modeling considering stratigraphic uncertainty. The framework consists of model parameter identification, conditional simulation, and stratigraphic uncertainty quantification. Both boundary-based and category-based stratigraphic models are adopted in the framework, and a heuristic combination model is further recommended to combine the advantages of the boundary-based and category-based models. The geological stratification at a construction site in Hong Kong is characterized to illustrate the probabilistic framework. Results indicate that probabilistic stratification modeling quantifies stratigraphic uncertainty in a rigorous manner. Additionally, the heuristic combination model has the ability to generate almost arbitrary geotechnical strata and to account for material spatial distribution trends and engineering judgment to a certain degree.