Brenner Base Tunnel

Brenner Base Tunnel

Exploratory Tunnel Aica–Mules
Overview
Location	Brenner Pass
Status	Under construction
System	Brenner railway
Start	Innsbruck,Austria
End	Franzensfeste,Italy
Operation
Work begun	2008
Constructed	2007–present
Opened	Scheduled 2032
Traffic	Freight trainsandpassenger trains
Character	Twin tube Passenger and freight Third exploratory tunnel
Technical
Length	64km(40mi)
No.oftracks	Double track
Track gauge	1,435 mm(4 ft8+1⁄2in)standard gauge
Electrified	Electrified 25 kV 50 Hz AC
Operating speed	Passenger: 250 km/h (155 mph) Freight: 120 km/h (75 mph)
Highest elevation	840 metres (2,760 ft)
Tunnel clearance	8.1 metres (27 ft)
Grade	Austria 7.4/1000 Italy 5/1000
Route map
Brenner Base Tunnel Lower Inn railway toRosenheim Lower Inn railway toInnsbruck bridge overriver Inn Innsbruckbypass North portal Ampassshaft Brenner Base shaft North portal toInnsbruck Ahrental shaft Wolf shaft Italy-Austriaborder Mauls/Mules shaft Aicha/Aica shaft Brenner Base Tunnel South portal Brenner railway toBrenner/Brennero Franzensfeste Brenner railway toBrixen Riggertal/Val Riga shaft Albeins/Albes shaft Eisack/Isarcobridge Brenner Railway Klausen/Chiusashaft Brenner railway toWaidbruck/Ponte Gardena Brenner railway toBolzano/Bozen Laives/Leifers-Steinmannwaldshaft Brenner railway toBolzano/Bozen Brenner railway toVerona

TheBrenner Base Tunnel(German:Brennerbasistunnel;Italian:Galleria di base del Brennero) is a 55-kilometre-long (34 mi)railway tunnelunder construction through the base of theEastern Alpsbeneath theBrenner Pass.Upon completion, it will be the second or third longest railway tunnel in the world, after theGotthard Base Tunnelin Switzerland and (depending on their relative completion dates) theMont d'Ambin Base Tunnelbetween France and Italy. It will run from nearInnsbruck,inAustria,toFranzensfeste/Fortezza,inItaly,replacing part of the currentBrenner railway.The line is part ofLine 1,the Berlin to Palermo route, ofTrans-European Transport Networks(TEN-T).

TheBrenner Pass,in the Alps at the border between Austria and Italy, is one of the most important traffic connections between northern and southernEurope,and the motorway going over it is infamous for its frequent traffic jams.Pollution from transit traffic is a major concern because of the combination oftemperature inversionwith the narrow shape of the valleys leading to the pass.

The goal is to relieve this situation by greatly improving the railway connection betweenNorth TyrolandSouth Tyrolwith the new tunnel, which will allow trains to cross the Alps much faster. Currently, speeds in the Brenner region barely exceed 70 km/h (43 mph) due to the steepness of the existing tracks, which cross the pass at an elevation of 1,371 metres (4,498 ft) above sea level.

The travel time fromInnsbrucktoBolzanowill be reduced from current 2 hours to just 50 minutes.

The project is funded by Austria and Italy with large contributions by theEuropean Union.Together with theInntal Tunnel,part of the existingInnsbruck bypass,the Brenner Base Tunnel will reach a length of 64 kilometres (40 mi), which would be the longest underground railway connection in the world. The tunnel is scheduled to be completed in 2032.

Background

The passenger and freight traffic across the Alps has increased greatly in recent years and further growth is forecast.Austria is a key country in movement of freight between northern and southern Europe and between eastern and western Europe. The Brenner region is very politically sensitive with respect to both local and cross-border transport issues. Between 1970 and 1999, highway freight increased seven-fold. (3 million to 22 million tonnes) In 1990, 70% of the freight from eastern Europe was transported by rail and the remainder by trucks. These proportions were expected to reverse by 2010. About three-quarters of traffic through the Brenner Pass is currently carried by road transport. Local residents have long fought for relief from the associated pollution. The construction of a rail tunnel is considered by its proponents to be necessary for a shift of freight traffic from road to rail.

The railway line from Innsbruck to Bozen was built between 1860 and 1867. Tight curve radii and gradients of up to 2.6% complicate rail operations. However, improvements on the Italian side in recent years to the existing line, which were completed in late 2008, allow the line theoretically to accommodate 240 trains per day. The grades were not significantly improved.

The new Brenner line would have a maximum gradient of 0.4%-0.7%. Thus, a locomotive would be capable of hauling more than double the weight. The new line (thebase tunneltogether with the southern approach fromWaidbruck/Ponte GardenatoFranzensfeste/Fortezza) would cut travel time between Innsbruck and Bolzano from about two hours today to less than half that.

Project

Main tunnel

The 55-kilometre (34 mi) long, twin-tube tunnel begins in the Innsbruck suburb of Wilten and penetrates theAlpsreaching a height of about 840 metres (2,760 ft) above sea level (ASL). The tunnel will be up to 1,720 m (5,640 ft) below the surface at its deepest point in thegneisssection stretching south from the Italian border.Since under the most recent plan the tunnel starts as a twin-tube tunnel, the junction already prepared in theInntal tunnelon theInnsbruck bypasswill not be used. Instead, a diversion with several branches is planned.

The volume of rock to be excavated during the construction of the tunnel is estimated at 21 million cubic metres (740 million cubic feet), of which approximately 60% will be incurred in Austria, as about 60% of the tunnel will be in Austria. A part of the spoil will be used asfillfor the approach lines and another part of the spoil material is used to produce the concrete segment for the final lining of the tunnel. The main tunnels will have a circular cross section with a diameter of approx. 8.1 m (27 ft).

According to current planning the apex of the tunnel will be at the border at an altitude of about 810 m (2,660 ft) ASL, although an apex farther south would have been lower. The placing of the apex at the border is set out in the treaty between Austria and Italy. As justification for this choice it is stated that this will allow Austrian water to run in the tunnel to Austria and Italian water to Italy.

Northern approach

On its north end, the base tunnel (BBT) has two entrances, which must go underground a few kilometres before the junction with the main tunnels, and will also be built as part of the BBT. One route leads from the main Innsbruck station underBergiseland the other connects with the Innsbruck bypass. This route adds about 8 kilometres (5.0 mi) more to the length of the tunnel than the Innsbruck station route; with it included, the BBT, at 62.7 kilometres (39.0 mi), would become the longest continuous railroad tunnel in the world. However, if the Axentunnel extension is added to theGotthard Base Tunnel,its length would become 75 kilometres (47 mi), allowing it to reclaim the 'longest tunnel' title.

The northern approach from Munich within Germany is the 165 kilometres (103 mi)Grafing–Rosenheim–Kufsteinroute. The "Brenner Nordzulauf" (Brenner northern link) project aims to construct a high-speed line for speeds of up to 230 km/h (143 mph) betweenGrafingandBrannenburgin addition to the existing line, adapting the route's capacity to the projected increase as a result of the BBT. The project has reached in-depth planning stages but suffers from lacking support by locals.A more direct route between Munich and Innsbruck, for example, viaGarmisch-Partenkirchen,MittenwaldandSeefeldwas not pursued, though it could have shortened the Munich Innsbruck line to 129 kilometres (80 mi).

In Austria, anew double-track high-speed linesupplements theLower Inn Valley railwaybetweenWörglandBaumkirchen.It manages to cut travel time between Munich and Innsbruck from 1:50 via the old tracks to merely 0:55 using the high-speed line.About 32 kilometres (20 mi) of the 40-kilometre (25 mi) line through theLower Inn Valley(Unterinntal) is built underground, in troughs, or under snow sheds. Noise and vibration mitigation is accomplished by the use of 80,000 square metres (860,000 sq ft) of elastomer in amass-springsystem. The segment's track superstructure is load class E5. It is capable of handling 260-300 trains per day.This section was opened 2012-12-09.Planning is under way on the continuation of this line to the German border at Brannenburg.

The southern approach for the BBT will be 189 kilometres (117 mi) long and reach from the southern portal of the tunnel in Franzensfeste/Fortezza toVerona.Planning has been completed for some sections.

• 
  Start of theTBMatAichaconstruction site in April 2008
• 
  View of theEisackunderpass construction site in September of 2019
• 
  TBM at theAhrental–Pfonsexploratory tunnel
• 
  Excavation materialprocessing plant and depot in Ahrental in July 2016

History

The Brenner tunnel is the most important link in theBerlin–Palermo railway axis,a series of projects that will create a single railway line fromBerlininGermanytoPalermoinSicily.In April 2003, the governments of Austria and Italy signed an agreement to build the tunnel.

Schedule history

Early in the preliminary planning, at a Brussels meeting in June 2005, BBT SE (Brenner Base Tunnel Societas Europae), presented an interim status report. Expectations following the meeting were that the project could be finalized and the pilot tunnel started by 2006. The target for the tunnel to start service was 2015.

In 2007 a construction timeline with a 2022 finish date was specified in a memorandum signed by the Austrian and Italian ministers of transport.

Funding history

In December 2008Antonio Tajani,the European commissioner for transport, approved funds totalling €1.7 billion to finance 11 railway projects that together should establish two major routes across the continent.

In May 2009 it was confirmed that final go-ahead for the project had been given.

The final estimated cost was put at €8.384bn at 2018 levels.

Construction history

In the summer of 2007 work started on a pilot tunnel to run along the line of the future tunnel and to be used for removing water and spoil during the major construction phase. Construction of the pilot tunnel between 2006 and 2009 was estimated to cost €430 million and would be 50% EU funded.

On 6 July 2019, two Austrian segments were connected, and an unbroken 36 kilometres (22 mi) long tunnel was formed – around 65% of the tunnel's 55 kilometres (34 mi) projected length.

Design

The final design will consist of two tunnels, 55 kilometres (34 mi) long. A centre tunnel 12 metres (39 ft) below the two primary tunnels will be used during construction as a guide tunnel to determine geological conditions, and later for drainage and emergency access. There will be a cross over between the tunnels every 333 metres (1,093 ft). Multi-function stations will be located at Trens (inFreienfeld), St. Jodok, and a third station towards the northern end of the tunnel to provide operational and emergency services.ETCSLevel 2 will be installed to provide train control.

Funding

As the transalpine stretch of the SCAN-MED Corridor, the Brenner Base Tunnel receives substantial funding from the European Union. Between 2015 and 2023, 50% of the costs for the exploratory tunnel (about 330 million Euro) and 40% of the costs for the two main tunnels (about 880 million Euro) were covered by the EU. Austria and Italy will each cover half of the remaining costs.

The 2017 estimate of the basic costs for the Brenner Base Tunnel was 7.8 billion Euro. Considering the planned end date for the project (2028), the estimate total costs, with risk provision and adjustment for inflation are about 8.384 billion Euro. They can be divided into 4 large categories: 60% of the cost comes from the engineering works, 15% is for outfitting, 10% is for planning, services and internal costs, 1% for parcels of land and related issues and 14% for risk provision.

Specifications

Cutaway view of the Brenner Base Tunnel

Source:

• Total tunnel length from the Innsbruck bypass to Fortezza/Franzensfeste: 64 km (39.768 mi)
• Length from the Innsbruck portal to the Fortezza/Franzensfeste portal: 55 km (34.175 mi)
• Diameter of each of the single-track tubes: 8.1 m (27 ft)
• Distance between cross passage tunnels: 333 m (1,093 ft)
• Elevation at highest point: 794 m (2,605 ft)
• Maximumoverburden:1,720 m (5,640 ft)
• Start of construction: 1999 (preparations), 2007 (exploratory section), 2011 (main tunnel)
• End of construction: 2032
• Total cost:€8.384 billion
• Electrification System:25 kV 50 Hz AC
• Control and command system:ETCS Level 2
• Operating speed: 250 km/h (155 mph) for passenger trains and 160 km/h (99 mph) for freight trains

See also

• NRLA
• Austrian Federal Railways
• High-speed rail in Italy
• Lyon Turin Ferroviaire
• Megaproject
• Treno Alta Velocità

External links

• BBT SE(English)
• (in Italian)Tunnel del Brennero: avviati i lavori alla presenza del Presidente Giorgio Napolitano
• Brenner Base Tunnel