Tunnelling, spelled with two n's, is the British English spelling of the word, while tunneling, spelled with one n, is the American English spelling. The IPA phonetic transcription for "tunnelling" is /tʌnəlɪŋ/. It's pronounced with a short "u" sound "tun," followed by a schwa sound "ə," and ending with "ling," which rhymes with "dangling." This word refers to the process of digging or constructing a tunnel, and is commonly used in the context of transportation infrastructure projects.
Tunnelling, also spelled as tunneling, is a term used to describe the process of constructing an underground passage or tunnel. It involves excavating or boring through various types of soil, rock, or other materials to create a passageway for transportation, water supply, utilities, mining, or any other purpose.
Tunnelling typically starts with the survey and design phase, where engineers and geologists assess the geological conditions, water table levels, and other factors to determine the most feasible route and construction methods. Once the design is complete, the excavation process begins, either by drilling and blasting through hard rock or using tunnel boring machines (TBM) for softer ground.
There are different types of tunnels, such as horizontal tunnels, vertical shafts, or inclined passages, depending on their purpose and location. Tunnelling can be carried out using various techniques, including cut-and-cover, drill and blast, sequential excavation, or shield tunnelling.
Tunnelling requires meticulous planning, engineering expertise, and specialized equipment to ensure the stability and safety of the tunnels. It may also involve the installation of support systems like linings, steel ribs, or shotcrete to prevent collapse or structural failures.
Tunnelling plays a vital role in connecting distant locations, providing underground transportation networks, supporting infrastructure development, and facilitating underground utility installations. It has a wide range of applications, from urban metro systems and road tunnels to mining operations and sewage networks.
The operation of cutting a passage through a hill or under a river, and arching the roof.
Etymological and pronouncing dictionary of the English language. By Stormonth, James, Phelp, P. H. Published 1874.
The word "tunnelling" is derived from the noun "tunnel", which originated in the late 15th century. The term "tunnel" comes from the Middle French word "tonel" or "tonnel", which means a "small cask" or "barrel". This sense of a cylindrical shape led to the word being applied to underground passages that were often cylindrical in shape. Over time, the spelling and pronunciation evolved, and the word "tunnel" came to refer specifically to underground passages. The verb form "tunnelling" simply derives from this noun.