2482 x 2480 px | 21 x 21 cm | 8,3 x 8,3 inches | 300dpi
Date de la prise de vue:
12 mai 1998
Lieu:
Switzerland, Europe.
Informations supplémentaires:
Cette image peut avoir des imperfections car il s’agit d’une image historique ou de reportage.
After cutting rock from the working face and disposing of the waste material (spoil), a tunnel boring machine (TBM) braces itself against the tunnel wall using huge hydraulic rams (pictured) and advances its cutter head section into the excavated space. The TBM head is then braced against the tunnel wall and the TBM rear section is dragged forward. Once this movement is completed, the TBM is ready to begin another excavation cycle. The first successful tunnelling shield was developed by Isambard Brunel to excavate the London Thames Tunnel in 1825. Brunel was inspired in his design by the shipworm after he noticed its efficiency at boring through submerged timber. In ancient times, the most active tunnellers were the Romans who created an extensive network of tunnels to carry water from mountain springs to cities and villages. They carved underground chambers and built elegant arch structures, not only to carry fresh water into the city but to carry wastewater out. In modern times, using the latest tunnel construction technology, engineers bore through mountains, under rivers, under seas and beneath huge cities. The rapid technological advances of today’s tunnel boring machines (TBMs) has seen highly sophisticated excavating machines become much larger in diameter, far more automated and capable of boring efficiently and quickly into harder, softer and water-bearing rock. This has allowed tunnel construction by means of TBM to become tunnel engineers’ preferred method of underground excavation, largely replacing the traditional use of potentially dangerous explosive devices (called drill and blast).
