Geotechnical risk management using the observational method

Abstract: There have been many cost overruns, time delays and quality problems reported from geotechnical engineering projects around the world during recent decades. Many of the reported problems are associated with risks related to the geotechnical conditions. To achieve a safe and cost-effective project with the desired quality, it is vital to adequately manage the geotechnical risks.The management of geotechnical risks includes a prediction of the geotechnical behavior. When it is difficult to predict the geotechnical behavior, the European design code, Eurocode 7, suggests the application of the observational method to verify the design. The main principle of this method is the use of observations and predefined measures to modify the design to comply with actual geotechnical conditions. Earlier research suggests that the observational method has the potential to manage geotechnical risks successfully, but the lack of guidelines related to its implementation has restricted the use of the method.The aim of this thesis is to enable a successful management of geotechnical risks in geotechnical engineering projects to improve quality and decrease costs related to geotechnical uncertainties.The research methodology used in the thesis was a multiple case study that included three geotechnical engineering projects. The case study was conducted in two steps, first an analysis of written information regarding the geotechnical risk management process in the projects, and then semi-structured interviews with key individuals involved in the geotechnical risk management process.The main research contribution is an increased knowledge of the key aspects for successful management of geotechnical risks, and the application of the observational method. Among other things, the thesis also discusses (1) the influence of the contractual framework on the management of geotechnical risks and application of the observational method, (2) management aspects of the observational method, and (3) the recommended roles of the actors involved in the risk management process.