A Case-based Analysis on Geotechnical Risk Allocation between Owners and Contractors and Their Implications for Construction Contracts: A Contract Theoretic and Coalition Game Approach to Evaluating the Effects of Geotechnical Risk Management

Abstract

 In construction projects, the increase in construction costs due to the geotechnical risks is still frequent, and while the need for geotechnical risk management by geotechnical engineers has been pointed out, there is room for further utilization of the technical skills of geotechnical engineers.

 In this study, we quantified the effectiveness of geotechnical risk management using the Sharpley value, a kind of cooperative game theory, and analyzed cases of construction projects with high management effectiveness. As a result, it was shown that management effectivensess under large-scale landslide risk are high, and we also summarized the characteristics of such cases.

 Then, the Geotechnical Baseline Report (GBR), a method for sharing geotechnical risk between client and contractor used by such as FIDIC, was formulated using contract theory in order to clarify the relationship between the characteristics of the construction projects and the optimal risk sharing. By using the model, it is shown that setting GBR after the occurrence of deformation, which is a precursor of landslide, may be effective as a geotechnical risk-sharing method for construction projects with large-scale landslide risk.