Principles of workplanning applied to a strategic infrastructure: the Bussoleno Interconnection Tunnel within the Turin-Lyon high speed railway corridor

As the construction projects become bigger and complex, workplanning and scheduling are becoming more and more important. Those processes guarantee the success of a project and the coordination of the work, respecting the times and the costs constraints, often imposed. Workplanning concerns the management of times and resources, which allows not only the correct control of the execution of the works but also temporal coordination between the professionals present on the construction site, in order to avoid interferences and associated risks. The aim of this Master's thesis is to study the excavation of a railway tunnel, in particular the Interconnection Tunnel of the Turin-Lyon high speed railway line, located between Susa and Bussoleno. This Tunnel will connect the new international Susa station to the historic line Turin-Modane. Based on the Definitive Project, the first part of the thesis is dedicated to the study of the excavation methodologies, the boundary geological and geotechnical conditions, the designed functional sections and their relationship with the support sections, the activities included in the excavation process and the related times. The scheduling process fits within the Definitive tender-based Project, following the D.lgs. 50/2016, and lays the basis for the following step, which is the Executive Project. This work is based on the use of the softwares Microsoft Project and Tilos, which are used to create the Gantt chart and the Time-Location Diagrams, respectively. Given the first Scenario, which corresponds to the Definitive Project, the second part of the thesis is focused on the study of three more Scenarios, in order to find the best solution in terms of time use and resources allocation. Those alternatives are based on different work strategies which are, for instance, the two-faces excavation of one way of the tunnel, or the use of the cross passages as intermediate accesses, trying to save time and to better distribute the working teams. The purpose of the second part of this work is not only giving a contribution to the optimization of the process and assessing a methodology that can be used in workplanning but also helping the companies in charge to design the Executive Project having a preliminary idea on the excavation times, the resources needed and to be guided to the choice that better fit their needs.