the basics of construction Five types of tunnel construction Tunnelling are commonly used: are excavated for many 1. Cut and cover tunnels. reasons, including transportation, Constructed in a shallow trench utilities and mining. Tunnellers and covered over. Example: differ from miners as they dig to Metropolitan railway, 1886 create a construction of a pre- 2. Bored tunnels. Made using The patron saint of defined shape and length. Miners, shields and tunnel boring tunnellers is Saint on the other hand, dig to recover machines without removing the Barbara, whose image a specific ‘spoil’ of mineral and ground above. Usually circular is often depicted at the metal deposits. in shape or horseshoe cross- entrance to tunnelling section. Crossrail, 2018 Tunnel construction is one of the works most complex civil engineering 3. Immersed tube tunnels. These challenges there is. Engineers study are sunk into a trench on the the varying types of ground conditions seabed. Proposed Fehmarn Belt before commencing excavation 4. Drill and blast. Explosives underground. These include: are used to blast away sections • soft ground of hard rock. Sections of the • hard rock Gotthard Base Tunnel, 2016 • soft rock 5. New Austrian Tunnelling • underwater (immersed) tunnels Method. Soft ground. A sprayed In addition, they must examine concrete lining is applied after groundwater conditions, proposed face advance is achieved. Box Tunnel Mersey Tunnel Simplon Tunnel Channel Tunnel Gotthard Base Tunnel tunnel length, diameter and depth, LONDON, UK, 1843 wiltshire, uk, 1841 LIVERPOOL, UK, 1886 Switzerland - ITALY, 1905 ENGLAND - FRANCE, 1998 SWITZERLAND, 2016 as well as the construction’s final use key tunnelling projects and shape. They also need to apply This engineering marvel came about due Isambard Kingdom designed and This 3,920m road tunnel opened in 1886 and This 19,800m rail tunnel connected Geneva A 34km tunnel was bored under the English Enabling rapid rail travel between Zurich and From London’s Thames Tunnel to Marc Brunel’s tunnelling shield invention oversaw construction of a 2,940m tunnel remains the fastest way to cross the Mersey and Milan via the Alps. Built by Swiss Channel to create a fixed link between Milan, the tunnel runs for 57km. It was built appropriate methods for lining the of 1843 to the 2016 Gotthard that was inspired by his observations of the cutting through Box Hill to carry the Great estuary from Birkenhead to Liverpool to this engineers, it was at the time the longest rail England and mainland Europe. Three tunnel using the latest tunnel boring technology and tunnel to counteract compression Base Tunnel discover our six shipworm boring its way through timber. Bricks Western Railway from London to Bristol. day. Chief Engineer, Francis Fox brought in a tunnel in the world. A system of twin tunnels boring machines dug from either side, meeting lots of explosives. Twin tunnels were dug with forces from the surrounding ground and extra strong cement lined the tunnel’s He used gunpowder to blast through the tunnel boring machine, complete with rotating with cross passages delivered fresh air to the with great celebration in the middle. There regular crossover points linking platforms for epoch-making projects. > exposed parts. limestone. arm with teeth to rip out chunks of rock that construction workers. are two main rail tunnels and a smaller service passenger safety. and to keep it watertight. were then carried away on a conveyor belt. tunnel.