Brenner Base Tunnel: The longest railway tunnel in the world
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onstruction is currently underway on the Brenner Base Tunnel (BBT), more than half a kilometre below the Brenner Pass in the Alps. When completed, it will be the world’s longest underground railway connection, spanning 64 km from Fortezza in Italy to Innsbruck/ Tulfes in Austria. The BBT is part of the broader ScandinavianMediterranean Corridor which will unite Verona with Munich. It is one of nine core corridor networks that have been identifie by the EU for funding, based on the strategic part that it plays in the Trans-European Transport Network (TEN-T). Research shows that about 40% of transalpine traffic passes through the Brenner Pass. Since Roman times, the Pass has provided a link between the main areas of Western, Central and Mediterranean Europe. The Brenner railway which was built in 1867 has the capacity to handle 260 trains per day. It traverses steep up and downhill slopes. The base tunnel is being built on a virtually horizontal line and will have the capacity to handle 400 trains per day, 80% of which is expected to be freight trains. The tunnel will reduce the total rail distance between Fortezza and Innsbruck by about 20 km, reducing transit time from 80 to 20 minutes on the high speed train.
Promotion
A State Treaty was si for the construction 2004. The tunnel w mobility in the region
1. Removing the in impede trade
2. Fostering growth coordinated plan
3. Promoting a faste friendly transpor across Europe.
The area in which experiences environm by the high levels o emissions and nois negative effect on the and presents as a ma area. Despite high lev only one third is bein completed, freight tra shifting from trucks o significant envi onme
of intermodality
igned between Austria and Italy of the BBT on the 30th April will increase connectivity and by:
nfrastructure bottlenecks that
h, cross-border cooperation and nning
er, efficient and environmentally rt for passengers and freight
the Brenner Pass is located mental degradation occasioned of traffic which generates toxic se pollution. This has had a e quality of life of the inhabitants ajor deterrent for tourism in the vels of freight transport passing, ng moved by rail. When BBT is affic will be rerouted underground onto trains. This will represent a ental gain for the town.
BBT SE BBT SE is a ‘special vehicle’ European public limited company which has been set up for the planning and construction of the BBT. Ownership of the tunnel vests in Austria and Italy who are equal shareholders in BBT SE. Austrian holding company OBB (Österreichische Bundesbahnen Infrastruktur AG) and the Italian counterpart TFB (Tunnel Ferroviario del Brennero Holding AG) both hold 50% of the company’s shares. The EU co- finances the BBT for up to 40%. Progress of the construction and the usage of finance is closely monitored by the EU and this will influence whether or not they continue to provide grant funding to the project. The balance of the
cost (60%) is then split equally between Italy and Austria. The expected cost of the project is â‚Ź 8.6 billion. The BBT SE is governed by a Supervisory Board of 12 members, 6 named by the Austrian and 6 by the Italian partner in BBT SE. A dual management system whereby the company is managed Raffaele Zurlo the Italian CEO and Konrad Bergmeister the Austrian CEO.
High capacity rail link Some 11.1 million cubic metres of rock will be carved out of the Alps by the time the project is completed. The project involves the construction of two single track tunnels with connecting side tunnels at intervals of 333m and an exploratory tunnel built below the two main tunnels. It will be used to assess geological risks though pre-construction rock mass prospection. Both conventional blasting and mechanised excavation methods will be used on the project, based on the conditions of the rock mass and the length of the stretches to be excavated.
Project Timelines 1999-2003 Phase I:preliminary project and prospection 2003- 2010 Phase II: final project and environmental impact assessment 2007- 2018 Phase II (a): exploratory section 8
The Sustainable Business Review - Quarter 4 2016
2011- 2025 Phase III: exploratory tunnel and main tunnel 2026- Tunnel will be operational There are four construction sites which are currently in operation:
Tulfes-Pfons The biggest award made of the four
is for the Tulfes – Pfons construction lot amounting to 380 million Euro and awarded to the Strabag/SaliniImpregilo bidding consortium 2014. Excavation works on the 38km tunnel began in September 2014 and is due to be completed in 2019. The work on the Connecting tunnels between the Tunnel and Innsbruck bypass has commenced in 2015
i)Wolf Excavation work for Wolf began in 2013 and is expected to be completed at the end of 2017. The project is worth 104 million Euro and was awarded to the Swietelsky/Swietelsky Tunnelbau bidding consortium in 2013. Work has been completed on the tunnels and rerouting the Padaster brook.
They are currently busy with the installation of the concrete track bed and 1.2 km of exploratory tunnel to be excavated, a junction chamber and connecting tunnels.
ii) Periadriatic Line This section crosses the large fault zone known as the Periadriatic seam which is a major tectonic discontinuity in the Alps. The construction lot was awarded to the Strabag/Salini-Impregilo bidding consortium in 2011 and is worth 53 million Euro. Since October 2011, 3.7 km of the main tunnels and 1.5km of the exploratory tunnels have been excavated. The stretch near the Periadriatic seam was excavated using blasting and was accomplished without any problems. The work is expected to be completed this year.
iii) Isarco River underpass The construction work for the underpass was awarded to Salini Impregilo in consortium Strabag, and is worth 301 million Euro. The Isarco River underpass is located just before entering the railway station at Fortezza and is regarded
as extremely complex from a technical perspective. Both the main tunnels as well as the interconnecting tunnels will pass under the Isarco River. The project started in 2014 and will cover civil works for the two main tunnels
(4.3 km) and the two interconnecting tunnels (2.3km) and will be completed in 2022. The project links the BBT with the existing Brenner line and the
railway station in Fortezza. Prior to excavation of the main tunnel tubes, preparatory works needs to be done which involves the re-routing of state road SS12, the construction of two bridges, one over the Isarco river and one over the Rio Bianco brook, a new railway underpass and the building of an access road to the A22 highway with a loading and unloading area. This will bring welcome relief to the surrounding towns as freight transport will be routed from the town to the highway. In this area, the tunnel is designed to run beneath the surface of the river and through groundwater requiring the use of the complex excavation processes of ground freezing and jet grouting. Ground freezing was used to stabilise soil, so it will not collapse near the excavations. Liquid nitrogen was used in this project to freeze the ground, making it as hard as concrete.
Jet grouting is suitable for soft marine clay found on the riverbed. It uses a high kinetic energy jet of fluid which loosens the ground and then this is mixed with a thin slurry producing a soil-cement material.
Tunnel tourism A significant infrastructure project like the BBT always attracts tunnel tourist. They cater for tunnel tourist through the two information centres located at Steinach and Fortezza which have been set up with over 1000 m2 of exhibition space, fully equipped with
wall charts, models and videos for young visitors and experts. They show the planned tunnel route as well as provide information on the geological makeup of the rock mass and the construction work. Construction site tours are a popular attraction.
Improved road safety envisaged by modal shift It is expected that the modal shift from road to rail envisaged by the project will realise an improvement of transport safety standards. Research shows that when compared to other modes of transport, high speed rail
transport experiences the lowest incidence of accidents, injuries and death. The BBT design fulfils all safety standards of railway transport with design features of two separate tunnels which are connected to each other at intervals of more than 300 metres and the additional feature of intermediate stations which allow for evacuation to the surface fulfils all current safety standards of railway transport.
Monitoring the environmental impact of the construction All the environmental aspects that
could be negatively impacted by the construction of the tunnel are monitored by a third party. The monitoring commenced prior to the implementation of the project and will continue throughout the lifecycle of the project as well as after the project has ended. Any environmental issues are dealt with promptly through corrective measure. Verificatio of the efficiency of any mitigation strategies takes place as well as verification of general compliance with the content and any provisions or recommendations formulated in the environmental compatibility decree.
Galleria di Base del Brennero Brenner Basistunnel BBT SE Piazza stazione 1 I-39100 Bolzano T.: +39 0471 06 22 - 0 F.: +43 0471 06 22 - 11 https://www.bbt-se.com/en/
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