Risk Assessment in Geotechnical Engineering Practice: Fid-Bau Portal

Risk Assessment in Geotechnical Engineering Practice

Sartain, Nick / Mian, Juliet / Peluso, Dan

This paper presents a number of case studies where quantitative or semi-quantitative tools were used to evaluate risks and hence make design or management decisions, and describes the benefits of this approach over a deterministic assessment. The situations described are beyond the scope of geotechnical design codes which, although they contain the requirements for geotechnical design to a societally acceptable level of reliability, tend to do so for specific elements such as a pile or wall or earthwork. There are many situations in geotechnical engineering where design codes are not sufficient and in these cases the designer may choose between a deterministic ‘worst credible’ approach, or a risk-based approach to solve the problem. This paper describes the risk assessment principles and presents the application of these principles in three case studies. The case studies reviewed are the Gautrain in South Africa, which had to be designed to cross dolomitic ground with the potential for large sinkholes; the risk-based assessment of existing transport infrastructure earthworks in the U.K. to manage safety and assess resilience in the event of heavy rainfall; and the Pajaro Dunes Seawall in California which required remediation in a cost-effective manner considering hazards such as beach erosion, wave run-up and storm damage.