CE 439

1. CE 439 Railway and Metro Tunnels

2. CE 439 subjects • History of railway and metro tunnels • Preliminary studies and design Considerations • Ground treatment • Loads on tunnels • Cut and cover / slurry wall method • Drill and blast method • Shields and tunnel boring machines • Observational method and NATM • Immersed tunnels • Metro systems • Tunnel safety

3. Final mark • Home assignment: 30% • Term test: 30% • Final examination: 40%

4. Characteristics • Tunnel = 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 sectionsand mostly or fully independent from road traffic

5. 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 prefabricatedtunnel elements into a dredged channel and joining them up under water • Concrete • Steel

6. Terminology Excavation in multiple drifts

7. Terminology • Crown: The uppermost part of the tunnel • Drift : A horizontal excavation • Heading : The excavated face of the tunnel • Invert : The bottom (floor) of the tunnel • Wall : The side of the tunnel • Portal : The tunnel entrance • Springline : The line at which the tunnel wall breaks from sloping outward to sloping inward toward the crown • Station : The distance measured from the portal (chainage)

8. Railroad passenger traffic Km travelled per passenger in the year 2000 41 trips/year 29 trips/year Source: Danish State Railroads (DSB)

9. 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.

10. 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.

11. 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.

12. 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.

13. Construction progress for tunnels construction

14. Longest tunnels in operation (2001)

15. Tunnels under construction

16. Classification of tunnels by position or alignment • Saddle and base tunnels

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

18. Looping Tunnels

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

20. Ankara Extension Odtü Ümitköy Extension

21. CE 439 Course website: http://www.ce.metu.edu.tr/~CE439