The risk minimization strategy designing the tunnels of Greater Paris metro project
In the context of the Greater Paris Project, aimed to empower the actual Parisian Metro Network, SYSTRA is in charge of the design of the southeastern section of Line 15. This stretch consists of a 21km long bored tunnel, 8 underground stations and 25 safety and ventilation shafts, located in a densely urbanized area. One-track and double-track tunnels up to 8.70m of inner diameter have been designed to be bored by 7 TBMs. In such a project, the main technical challenges are represented by a very varied geology, ranging from limestones to sands and swelling clays; 3 river intersections; water pressures up to 5 bar;, existing ancient mines and all sort of sensible private and public structures potentially impacted by the excavation works. In this context, SYSTRA applied all along the design stages a Risk Management strategy in order to assess, analyze and minimize the technical risks with significant results in terms of planning and budget. The paper illustrates the challenges of the project, the technical design solutions and the risk management strategy used to handle its complexity and to optimize the design of the tunnels. to type your Full Paper.