Application of risk management plan to technical risks in metro construction: Case study of the Grand Paris Express project

This article presents the application of Risk Management Plan (RMP) to technical risks in metro construction. The RMP defines a balanced risk allocation between client, designer and contractor, and outlines technical and financial solutions in the occurrence of doubted events. It is an iterative process, and an approach of continuous improvement from design phase to construction phase, and aims to identify potential hazards, quantify relative risks, and implement adequate preventive measures and mitigations to avoid and reduce risks whilst identifying what actions are to be taken if risks occur. After the RMP presentation, a case study of the Grand Paris Express (GPE) project is then introduced in the French context. The GPE project is the largest metro project underway in Europe, comprised of 68 new metro stations and 200 km of additional tracks. It is located in an urban area with high technical risks. Throughout this case study, examples of how the RMP was applied to the technical risks such as geological and geotechnical risk, damage risk to neighbouring structures or assets and environmental risk are provided. The major identified risks are analysed with preventive measures, sometimes already integrated in the design, and technical solutions retained for the construction, as well as mitigation measures. In addition, the management of new risks that appeared during construction is presented, with a specific example involving the use of steel fibre-reinforced concrete tunnel segments. Finally, the contract management and insurance to accompany the RMP application in risk management are also covered.