CE 439

Railway and Metro Tunnels

CE 439 subjectsHistory of railway and metro tunnelsPreliminary studies and design ConsiderationsGround treatmentLoads on tunnelsCut and cover / slurry wall methodDrill and blast methodShields and tunnel boring machinesObservational method and NATMImmersed tunnelsMetro systemsTunnel safety

Final mark

Home assignment: 30%Term test: 30%Final examination: 40%

CharacteristicsTunnel = a subsurface passageway for passengers or goods through obstacles.

Purpose of the tunnel may be rail, road or pedestrian traffic, or to convey water, electric power, gas, sewage etc. Traffic tunnels are approximately horizontal, but possibliy built with a gradient for drainage.

Metro: An underground urban transportation system, self-contained, fully independent from road and other rail traffic.Light rail networks: (Stadtbahn, Metrotram) An urban network with some underground sections and mostly or fully independent from road traffic

Rough classification of methods

Deep excavation: An excavation process without removing the overlying rock or soil

• Steps: excavating-remove muck-supporting-lining-ventilation-draining

• Drill & Blast, shield, TBM, hammer, roadheader, NATM....

Cut and cover: trenching to excavate and construct a tunnel, and then backfilling earth over it.Immersed tunnel: lowering prefabricated tunnel elements into a dredged channel and joining them up under water

• Concrete• Steel

Terminology

Circular Horseshoe Vertical walls arch roof

Transportation tunnel cross-sections

Wal

l

Crown

SpringlineCore (strozze)

Invert

Top heading

Bench

Bottom

Excavation inmultiple drifts

Terminology

Crown: The uppermost part of the tunnelDrift : A horizontal excavation Heading : The excavated face of the tunnelInvert : The bottom (floor) of the tunnelWall : The side of the tunnelPortal : The tunnel entranceSpringline : The line at which the tunnel wall breaks from sloping outward to sloping inward toward the crownStation : The distance measured from the portal (chainage)

Railroad passenger traffic

0

400

800

1200

1600

2000

Switzerland France Denmark Holland Germany EU England Sweden Finland Norway

Km travelled per passengerin the year 2000

Source: Danish State Railroads (DSB)

29 trips/year

41 trips/year

The oldest tunnel, for the expressed purpose of communication was constructed 4000 years ago in ancient Babylon to underpass the bed of river Euphrates and to establish an underground connection between the royal palace and Temple of Jove.

The length of the tunnel was 1 km and it was built with the considerable cross-section dimensions of 3.6 m by 4.5 m. The tunnel, which was built in an open cut, would be a considerable project even according to modern standards. This shows us that, this tunnel was not the first of its kind built by the Babylonians and that they must have acquired skill and practice with several tunnels built earlier.

To appreciate the grandeur of the undertaking it should be remembered that the next subaqueous tunnel was opened about 4000 years later, in 1843, under the River Thames in London.

History and Development of Railway Tunnels

The first railway tunnel for horse drawn operation was constructed in France 1826 on the Roanne-Andre Cieux line.After James Watts invention of the steam engine a steam traction railway tunnel; Liverpool-Manchester line in England was constructed between 1826 and 1829. Hand operated steel rods were abandoned and hydraulic rock drills were introduced in 1857, during the construction of the Mont Cenis Railway tunnel between France and Italy. Invention of dynamite by Alfred Nobel in 1866 resulted in the new technique; the Drill and Shot method, and it was possible to excavate the hardest rock. Thus Mont Cenis, a 12,8 km tunnel, opened to traffic in 1871.The great Alpine tunnels between Italy-Germany, Italy-France, Italy-Switzerland, and Germany-Austria were completed in 25 years until 1913.Modern railway construction started with the Liverpool and Manchester Railways opened in 1830, and involved tunnelling from the very beginning.

In UK, over fifty railway tunnels exceeding one mile (1,61 km) in length were completed between 1830 and 1890.The Mersey Railway Tunnel (1879-86) and the Severn Tunnel (1873-86); two sub-aqueous railway tunnels, were built in that period beneath tidal rivers. Colonel Beaument’s Tunnelling machine, also used at this time in Channel Tunnel experiments, was used for much of the heading excavation, cutting a circular bore of 2.2 m diameter, and it was also used for ventilation headings on the Liverpool shore.In 1956, James Robbins showed the successful application of TBM in Toronto Subway. TBM application was forgotten for a long period since 19th century.At the beginning of 20th century there was a big gap between the tunnel construction and highway construction costs. In the second half of the 20th century, with the progress in development of both explosives and equipment, underground construction became feasible.In 1970, first Tunnelling conference held at Washington D.C among OECD countries.

Major Alpine Railway Tunnels

The Mont Cenis was the first Alpine tunnel, 1340 m above sea level, and 13.7 km in length. During the same period the Hoosac tunnel, “The Great Bore”, connecting Boston to the Hudson valley was being built in America (1855-1876). It was 7.44 km in length.The St. Gotthard was the second, 1164m above sea level, and 14.9 km in length. The Arlberg tunnel, 10.5 km long, links Austrian railways to Switzerland.The Simplon tunnel, 19.8 km in length, the longest of its kind.

Construction progress for tunnels construction

Time Progress Method

AD 41 7.5 cm/week Hand tools (some metal tools)

16th century 0.60 m/week Hand tools (better metal tools)

19th century 2.1 m/week Hand tools (use of explosives started)

19th century 6.3 m/week Use of mechanical drills started

1900-1950 30 m/week Hydraulic drills introduced

After 1950 60 m/week Jumbo drills used

After 1955 300 m/week TBMs introduced

After 1980 Increases… TBM

Longest tunnels in operation (2001) Tunnel Country Length Completed

Seikan (RR) Japan 55 km (23.3 km under water) 1988

Channel (RR) England-France 50 km (32 km under water) 1993

Daishimizu (RR) Japan 22.2 km 1982

Simplon (I&II) (RR) Italy-Switzerland 19.8 km 1906/1922

Shin-Kanmon (RR) Japan 18.6 km 1975

Gotthard Rail (RR) Switzerland 15 km 1881

Lotschberg (RR) Switzerland 14.6 km 1914

Laerdal Road Norway 24.5 km 2000

Gotthard Road Switzerland 16.3 km 1980

Tunnels under construction

Tunnel Country Length Expected

Gotthard Base Switzerland 57 km 2010

Lotschberg Base Switzerland 36 km 2010

Alpetunnel France-Italy 52 km 2015

Bolu Road Gümüşova-Gerede, Türkiye 3.32km 2003

Classification of tunnels by position

or alignment

Saddle and base tunnels

Profile of Lærdal – the world’s longest road tunnel on E16 between Oslo and Bergen in

Norway

Looping Tunnels

İstanbul

Traffic conditions in this densely populated city are getting worse while construction of a modern mass transit system is only progressing slowly.

Ankara

ExtensionOdtüÜmitköy

Extension

CE 439

Course website:

http://www.ce.metu.edu.tr/~CE439