Torino Metro Line 1 – Railway Technology

This article explores the technological advancements and infrastructural complexities involved in the construction and operation of Turin’s Metro Line 1. The project, a significant undertaking for the city of Turin, aimed to address growing transportation demands within a densely populated urban area. The focus will be on the technological innovations implemented throughout the project’s various stages, from tunnel boring techniques and signalling systems to the advanced rolling stock and security infrastructure. Examining the different phases of the project will highlight the challenges overcome and the resulting improvements in urban mobility for the citizens of Turin. This analysis will also provide insights into the financial aspects and the collaborative efforts of various organizations involved in delivering this complex railway project. The project’s success serves as a case study for future urban rail development, emphasizing the importance of integrating advanced technologies for efficient and sustainable public transportation.

Tunnel Construction and Engineering

The construction of Torino Metro Line 1 presented significant engineering challenges, primarily due to the extensive tunneling required. A total of 13 kilometers of tunnel were bored, accommodating two tracks to allow for bidirectional train movement. Four Herrenknecht Earth Pressure Balance (EPB) tunnel boring machines were employed to excavate the 6.9m-7m diameter tunnels. The tunnels reach depths ranging from 12 meters to a maximum of 24 meters. The tunnel lining utilized precast reinforced concrete segments, each weighing 23.6 tons and interconnected via 15 bib locks. The excavation process was meticulously monitored by Geodata’s Master system, ensuring safety and precision. Station sites were excavated using diaphragm walls constructed with a hydro mill. Waterproofing of construction joints and concrete defects was achieved through the application of a Penetron system, a solution from a US-based company, preventing leaks and maintaining structural integrity.

Signalling, Communication, and Security Systems

Torino Metro Line 1 incorporated advanced signalling, communication, and security systems to enhance operational efficiency and passenger safety. The signalling and control system, supplied by Siemens Mobility, ensures safe and reliable train operations. A sophisticated communications and video surveillance system was provided by Funkwerk Plettac (Germany), using Hewlett-Packard’s (HP) ProCurve switches for network infrastructure. A comprehensive CCTV network featuring 26 cameras per station (including cameras within trains, restrooms, and tunnel interiors) enhances security. The system also includes cameras strategically positioned at the Collegno depot’s technical maintenance site. The operations control center, located at the Collegno depot, is equipped with 28 monitors managed by an operator and a supervisor, allowing for real-time monitoring and response.

Rolling Stock and Operational Features

The metro line operates a fleet of 29 Val 208 trains supplied by Siemens, with an additional six trains on order to meet rising ridership demands. These four-car train sets, which can also be decoupled into two-car units, boast a capacity of 440 passengers (in the four-car configuration). The Val 208 trains feature rubber tires, providing smoother rides and reduced vibration. Each wheel is equipped with both traction and electrical brakes, ensuring safe braking performance. These trains attain a top speed of 80 km/h while operating on 750V DC current. Integrated electronic and communication systems allow passengers to easily contact station staff for assistance.

Project Overview and Conclusion

The Torino Metro Line 1 project, encompassing two completed stages and future expansion plans (Stages III and IV), represents a significant investment in Turin’s public transportation infrastructure. The project’s success highlights the crucial role of integrating cutting-edge railway technologies for efficient and secure urban transport systems. The project demonstrates the ability of a collaborative approach, involving various national and international companies, to successfully deliver a complex infrastructure project. The extensive use of innovative technologies, such as EPB tunnel boring machines, advanced signalling systems, and high-capacity rolling stock, contributed to a successful project outcome. The project’s financial structure included funding from the Italian State, Piedmont Regional Funds, Turin City Funds, and GTT (Gruppo Torinese Trasporti). The anticipated increase in ridership from 22 million passengers in 2010 to a projected 40 million by 2020 showcases the project’s impact on public transport in Turin.

Company Information:

• Herrenknecht: A leading manufacturer of tunnel boring machines.
• Geodata: A company specializing in geotechnical monitoring and project management.
• Penetron: A US-based company providing waterproofing solutions for concrete structures.
• Systra: An international engineering and consulting firm specializing in transport infrastructure.
• Metropolitana Milanese: A company involved in the Milan metro system.
• Studio Quaranta: An Italian engineering and architecture firm.
• Siemens: A global technology company involved in various aspects of the project, including rolling stock, signalling and automation.
• Tecnimont: An Italian engineering and construction company.
• Funkwerk Plettac: A German security technology company.
• Hewlett-Packard (HP): A technology company providing networking solutions.
• GTT (Gruppo Torinese Trasporti): The Turin public transport operator.