98-481: The Heathrow Airside Road Tunnel (ART) is a tunnel at Heathrow Airport . It connects the airside roads around Terminals 1 , 2 and 3 to those around Terminal 5 . The tunnel was opened to traffic in March 2005 and is used only by vehicles with security clearance to drive airside. The ART is 1.42 kilometres (0.88 mi) long, consisting of 60 metres (200 ft) of twin-cell cut and cover box at each end, linked by
196-587: A bolted concrete lining 0.45 metres (1 ft 6 in) thick: these are unusually strong tunnel segments, required because the ART is so close to the surface and, at one point, passes 3 metres (9 ft 10 in) over the top of the Heathrow Express tunnel to Terminal 4 . Each bore contains an unusual road layout, consisting of a single carriageway 6 metres (20 ft) wide; just wide enough to allow an airport bus ( Cobus 2700) to drive past another bus stopped at
294-732: A demonstrative ( þis , þat ), after a possessive pronoun (e.g., hir , our ), or with a name or in a form of address. This derives from the Old English "weak" declension of adjectives. This inflexion continued to be used in writing even after final -e had ceased to be pronounced. In earlier texts, multisyllable adjectives also receive a final -e in these situations, but this occurs less regularly in later Middle English texts. Otherwise, adjectives have no ending and adjectives already ending in -e etymologically receive no ending as well. Earlier texts sometimes inflect adjectives for case as well. Layamon's Brut inflects adjectives for
392-803: A dialect of Old French , now known as Old Norman , which developed in England into Anglo-Norman . The use of Norman as the preferred language of literature and polite discourse fundamentally altered the role of Old English in education and administration, even though many Normans of this period were illiterate and depended on the clergy for written communication and record-keeping. A significant number of Norman words were borrowed into English and used alongside native Germanic words with similar meanings. Examples of Norman/Germanic pairs in Modern English include pig and pork , calf and veal , wood and forest , and freedom and liberty . The role of Anglo-Norman as
490-449: A large factor in the decision making process. Civil engineers usually use project management techniques for developing a major structure. Understanding the amount of time the project requires, and the amount of labor and materials needed is a crucial part of project planning. The project duration must be identified using a work breakdown structure and critical path method . Also, the land needed for excavation and construction staging, and
588-493: A largely Anglo-Saxon vocabulary (with many Norse borrowings in the northern parts of the country) but a greatly simplified inflectional system. The grammatical relations that were expressed in Old English by the dative and instrumental cases were replaced in Early Middle English with prepositional constructions. The Old English genitive - es survives in the -'s of the modern English possessive , but most of
686-486: A lengthened – and later also modified – pronunciation of a preceding vowel. For example, in name , originally pronounced as two syllables, the /a/ in the first syllable (originally an open syllable) lengthened, the final weak vowel was later dropped, and the remaining long vowel was modified in the Great Vowel Shift (for these sound changes, see Phonology , above). The final ⟨e⟩ , now silent, thus became
784-488: A lesser extent), and, therefore, it cannot be attributed simply to the influence of French-speaking sections of the population: English did, after all, remain the vernacular . It is also argued that Norse immigrants to England had a great impact on the loss of inflectional endings in Middle English. One argument is that, although Norse and English speakers were somewhat comprehensible to each other due to similar morphology,
882-486: A more analytic language with a stricter word order. Both Old English and Old Norse were synthetic languages with complicated inflections. Communication between Vikings in the Danelaw and their Anglo-Saxon neighbours resulted in the erosion of inflection in both languages. Old Norse may have had a more profound impact on Middle and Modern English development than any other language. The effect of Old Norse on Old English
980-516: A pair of 1.3-kilometre (0.81 mi) long bored tunnels. The ART was designed and built between 1999 and 2004 by a team of engineers from the BAA (the tunnel's owner), Amec , Laing O'Rourke , Morgan Est - Vinci and Mott MacDonald . The bored tunnels have internal diameter of 8.1 metres (27 ft) and were driven by a 9.16-metre (30 ft 1 in) diameter Herrenknecht earth pressure balance tunnel boring machine . The excavations were lined with
1078-461: A pipe jack, with the span of some box jacks in excess of 20 metres (66 ft). A cutting head is normally used at the front of the box being jacked, and spoil removal is normally by excavator from within the box. Recent developments of the Jacked Arch and Jacked deck have enabled longer and larger structures to be installed to close accuracy. There are also several approaches to underwater tunnels,
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#17330859319071176-515: A process called apophony ), as in Modern English. With the discontinuation of the Late West Saxon standard used for the writing of Old English in the period prior to the Norman Conquest, Middle English came to be written in a wide variety of scribal forms, reflecting different regional dialects and orthographic conventions. Later in the Middle English period, however, and particularly with
1274-421: A specialized method called clay-kicking for digging tunnels in clay-based soils. The clay-kicker lies on a plank at a 45-degree angle away from the working face and rather than a mattock with his hands, inserts with his feet a tool with a cup-like rounded end, then turns the tool with his hands to extract a section of soil, which is then placed on the waste extract. Clay-kicking is a specialized method developed in
1372-561: A standard based on the London dialects (Chancery Standard) had become established. This largely formed the basis for Modern English spelling, although pronunciation has changed considerably since that time. Middle English was succeeded in England by Early Modern English , which lasted until about 1650. Scots developed concurrently from a variant of the Northumbrian dialect (prevalent in northern England and spoken in southeast Scotland ). During
1470-434: A tube can be sunk into a body of water, which is called an immersed tunnel. Cut-and-cover is a simple method of construction for shallow tunnels where a trench is excavated and roofed over with an overhead support system strong enough to carry the load of what is to be built above the tunnel. There are two basic forms of cut-and-cover tunnelling: Shallow tunnels are often of the cut-and-cover type (if under water, of
1568-710: A tunnel than a sufficiently strong bridge). Some water crossings are a mixture of bridges and tunnels, such as the Denmark to Sweden link and the Chesapeake Bay Bridge-Tunnel in Virginia . There are particular hazards with tunnels, especially from vehicle fires when combustion gases can asphyxiate users, as happened at the Gotthard Road Tunnel in Switzerland in 2001. One of the worst railway disasters ever,
1666-432: A tunnel. Bridges usually require a larger footprint on each shore than tunnels. In areas with expensive real estate, such as Manhattan and urban Hong Kong , this is a strong factor in favor of a tunnel. Boston's Big Dig project replaced elevated roadways with a tunnel system to increase traffic capacity, hide traffic, reclaim land, redecorate, and reunite the city with the waterfront. The 1934 Queensway Tunnel under
1764-452: Is allowed in this tunnel tube, and motorcyclists are directed to the other tube. Each level was built with a three-lane roadway, but only two lanes per level are used – the third serves as a hard shoulder within the tunnel. The A86 Duplex is Europe's longest double-deck tunnel. Middle English Middle English (abbreviated to ME ) is a form of the English language that was spoken after
1862-500: Is intended to carry both the Istanbul metro and a two-level highway, over a length of 6.5 km (4.0 miles). The French A86 Duplex Tunnel [ fr ] in west Paris consists of two bored tunnel tubes, the eastern one of which has two levels for light motorized vehicles, over a length of 10 km (6.2 miles). Although each level offers a physical height of 2.54 m (8.3 ft), only traffic up to 2 m (6.6 ft) tall
1960-433: Is now rare and used only in oxen and as part of a double plural , in children and brethren . Some dialects still have forms such as eyen (for eyes ), shoon (for shoes ), hosen (for hose(s) ), kine (for cows ), and been (for bees ). Grammatical gender survived to a limited extent in early Middle English before being replaced by natural gender in the course of the Middle English period. Grammatical gender
2058-487: Is relatively long and narrow; the length is often much greater than twice the diameter , although similar shorter excavations can be constructed, such as cross passages between tunnels. The definition of what constitutes a tunnel can vary widely from source to source. For example, in the United Kingdom, a road tunnel is defined as "a subsurface highway structure enclosed for a length of 150 metres (490 ft) or more." In
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#17330859319072156-401: Is sometimes necessary during the excavation of a tunnel. They are usually circular and go straight down until they reach the level at which the tunnel is going to be built. A shaft normally has concrete walls and is usually built to be permanent. Once the access shafts are complete, TBMs are lowered to the bottom and excavation can start. Shafts are the main entrance in and out of the tunnel until
2254-515: Is that the open building pit is muted after tunnel construction; no roof is placed. Some tunnels are double-deck, for example, the two major segments of the San Francisco–Oakland Bay Bridge (completed in 1936) are linked by a 160-metre (540 ft) double-deck tunnel section through Yerba Buena Island , the largest-diameter bored tunnel in the world. At construction this was a combination bidirectional rail and truck pathway on
2352-673: Is the Siloam Tunnel , built in Jerusalem by the kings of Judah around the 8th century BC. Another tunnel excavated from both ends, maybe the second known, is the Tunnel of Eupalinos , which is a tunnel aqueduct 1,036 m (3,400 ft) long running through Mount Kastro in Samos , Greece. It was built in the 6th century BC to serve as an aqueduct . In Ethiopia , the Siqurto foot tunnel , hand-hewn in
2450-556: The Balvano train disaster , was caused by a train stalling in the Armi tunnel in Italy in 1944, killing 426 passengers. Designers try to reduce these risks by installing emergency ventilation systems or isolated emergency escape tunnels parallel to the main passage. Government funds are often required for the creation of tunnels. When a tunnel is being planned or constructed, economics and politics play
2548-600: The Early Modern English and Modern English eras. Middle English generally did not have silent letters . For example, knight was pronounced [ˈkniçt] (with both the ⟨k⟩ and the ⟨gh⟩ pronounced, the latter sounding as the ⟨ch⟩ in German Knecht ). The major exception was the silent ⟨e⟩ – originally pronounced but lost in normal speech by Chaucer's time. This letter, however, came to indicate
2646-800: The Norman Conquest of 1066, until the late 15th century. The English language underwent distinct variations and developments following the Old English period. Scholarly opinion varies, but the University of Valencia states the period when Middle English was spoken as being from 1150 to 1500. This stage of the development of the English language roughly coincided with the High and Late Middle Ages . Middle English saw significant changes to its vocabulary, grammar, pronunciation, and orthography . Writing conventions during
2744-516: The Norman Conquest , had normally been written in French. Like Chaucer's work, this new standard was based on the East Midlands-influenced speech of London. Clerks using this standard were usually familiar with French and Latin , influencing the forms they chose. The Chancery Standard, which was adopted slowly, was used in England by bureaucrats for most official purposes, excluding those of
2842-688: The Northern England (corresponding to the Scandinavian Kingdom of Jórvík ), the East Midlands and the East of England , words in the spoken language emerged in the 10th and 11th centuries near the transition from Old to Middle English. Influence on the written languages only appeared from the beginning of the 13th century, this delay in Scandinavian lexical influence in English has been attributed to
2940-464: The Port Authority of New York and New Jersey was not aware of this bill and had not asked for a grant for such a project. Increased taxes to finance a large project may cause opposition. Tunnels are dug in types of materials varying from soft clay to hard rock. The method of tunnel construction depends on such factors as the ground conditions, the groundwater conditions, the length and diameter of
3038-797: The Queens-Midtown Tunnel between Manhattan and the borough of Queens on Long Island ; the Detroit-Windsor Tunnel between Michigan and Ontario ; and the Elizabeth River tunnels between Norfolk and Portsmouth, Virginia ; the 1934 River Mersey road Queensway Tunnel ; the Western Scheldt Tunnel , Zeeland, Netherlands; and the North Shore Connector tunnel in Pittsburgh, Pennsylvania . The Sydney Harbour Tunnel
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3136-466: The River Mersey at Liverpool was chosen over a massively high bridge partly for defense reasons; it was feared that aircraft could destroy a bridge in times of war, not merely impairing road traffic but blocking the river to navigation. Maintenance costs of a massive bridge to allow the world's largest ships to navigate under were considered higher than for a tunnel. Similar conclusions were reached for
3234-665: The United Kingdom of digging tunnels in strong clay-based soil structures. This method of cut and cover construction required relatively little disturbance of property during the renewal of the United Kingdom's then ancient sewerage systems. It was also used during the First World War by Royal Engineer tunnelling companies placing mines beneath German lines, because it was almost silent and so not susceptible to listening methods of detection. Tunnel boring machines (TBMs) and associated back-up systems are used to highly automate
3332-591: The canton of Glarus . The borehole has a diameter of 8.03 metres (26.3 ft). The four TBMs used for excavating the 57-kilometre (35 mi) Gotthard Base Tunnel , in Switzerland , had a diameter of about 9 metres (30 ft). A larger TBM was built to bore the Green Heart Tunnel (Dutch: Tunnel Groene Hart) as part of the HSL-Zuid in the Netherlands, with a diameter of 14.87 metres (48.8 ft). This in turn
3430-486: The water table . This pressurizes the ground ahead of the TBM cutter head to balance the water pressure. The operators work in normal air pressure behind the pressurized compartment, but may occasionally have to enter that compartment to renew or repair the cutters. This requires special precautions, such as local ground treatment or halting the TBM at a position free from water. Despite these difficulties, TBMs are now preferred over
3528-621: The 12th century, incorporating a unique phonetic spelling system; and the Ancrene Wisse and the Katherine Group , religious texts written for anchoresses , apparently in the West Midlands in the early 13th century. The language found in the last two works is sometimes called the AB language . Additional literary sources of the 12th and 13th centuries include Layamon's Brut and The Owl and
3626-422: The 13th century and was replaced by thorn. Thorn mostly fell out of use during the 14th century and was replaced by ⟨th⟩ . Anachronistic usage of the scribal abbreviation [REDACTED] ( þe , "the") has led to the modern mispronunciation of thorn as ⟨ y ⟩ in this context; see ye olde . Wynn, which represented the phoneme /w/ , was replaced by ⟨ w ⟩ during
3724-409: The 13th century. Due to its similarity to the letter ⟨p⟩ , it is mostly represented by ⟨w⟩ in modern editions of Old and Middle English texts even when the manuscript has wynn. Under Norman influence, the continental Carolingian minuscule replaced the insular script that had been used for Old English. However, because of the significant difference in appearance between
3822-467: The 14th century, even after the loss of the majority of the continental possessions of the English monarchy . In the aftermath of the Black Death of the 14th century, there was significant migration into London , of people to the counties of the southeast of England and from the east and central Midlands of England, and a new prestige London dialect began to develop as a result of this clash of
3920-597: The 1540s after the printing and wide distribution of the English Bible and Prayer Book , which made the new standard of English publicly recognizable and lasted until about 1650. The main changes between the Old English sound system and that of Middle English include: The combination of the last three processes listed above led to the spelling conventions associated with silent ⟨e⟩ and doubled consonants (see under Orthography , below). Middle English retains only two distinct noun-ending patterns from
4018-689: The 16th century as a metaphor for a narrow, confined space like the inside of a cask. Some of the earliest tunnels used by humans were paleoburrows excavated by prehistoric mammals. Much of the early technology of tunneling evolved from mining and military engineering . The etymology of the terms "mining" (for mineral extraction or for siege attacks ), " military engineering ", and " civil engineering " reveals these deep historic connections. Predecessors of modern tunnels were adits that transported water for irrigation , drinking, or sewerage . The first qanats are known from before 2000 BC. The earliest tunnel known to have been excavated from both ends
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4116-638: The 1960s. The main idea of this method is to use the geological stress of the surrounding rock mass to stabilize the tunnel, by allowing a measured relaxation and stress reassignment into the surrounding rock to prevent full loads becoming imposed on the supports. Based on geotechnical measurements, an optimal cross section is computed. The excavation is protected by a layer of sprayed concrete, commonly referred to as shotcrete . Other support measures can include steel arches, rock bolts, and mesh. Technological developments in sprayed concrete technology have resulted in steel and polypropylene fibers being added to
4214-687: The 1971 Kingsway Tunnel under the Mersey. In Hampton Roads, Virginia , tunnels were chosen over bridges for strategic considerations; in the event of damage, bridges might prevent US Navy vessels from leaving Naval Station Norfolk . Water-crossing tunnels built instead of bridges include the Seikan Tunnel in Japan; the Holland Tunnel and Lincoln Tunnel between New Jersey and Manhattan in New York City ;
4312-568: The Church and legalities, which used Latin and Law French respectively. The Chancery Standard's influence on later forms of written English is disputed, but it did undoubtedly provide the core around which Early Modern English formed. Early Modern English emerged with the help of William Caxton 's printing press, developed during the 1470s. The press stabilized English through a push towards standardization, led by Chancery Standard enthusiast and writer Richard Pynson . Early Modern English began in
4410-564: The Danelaw, this endings tended gradually to become obscured and finally lost, "simplifying English grammar" in the process. In time, the inflections melted away and the analytic pattern emerged. Viking influence on Old English is most apparent in pronouns , modals, comparatives, pronominal adverbs (like hence and together ), conjunctions, and prepositions show the most marked Danish influence. The best evidence of Scandinavian influence appears in extensive word borrowings; however, texts from
4508-691: The Middle Ages, crosses a mountain ridge. In the Gaza Strip , the network of tunnels was used by Jewish strategists as rock-cut shelters, in first links to Judean resistance against Roman rule in the Bar Kokhba revolt during the 2nd century AD. A major tunnel project must start with a comprehensive investigation of ground conditions by collecting samples from boreholes and by other geophysical techniques. An informed choice can then be made of machinery and methods for excavation and ground support, which will reduce
4606-418: The Middle English period varied widely. Examples of writing from this period that have survived show extensive regional variation. The more standardized Old English literary variety broke down and writing in English became fragmented and localized and was, for the most part, being improvised. By the end of the period (about 1470), and aided by the invention of the printing press by Johannes Gutenberg in 1439,
4704-675: The Middle English period, many Old English grammatical features either became simplified or disappeared altogether. Noun, adjective, and verb inflections were simplified by the reduction (and eventual elimination) of most grammatical case distinctions. Middle English also saw considerable adoption of Anglo-Norman vocabulary, especially in the areas of politics, law, the arts, and religion, as well as poetic and emotive diction. Conventional English vocabulary remained primarily Germanic in its sources, with Old Norse influences becoming more apparent. Significant changes in pronunciation took place, particularly involving long vowels and diphthongs, which in
4802-545: The Nightingale . Some scholars have defined "Early Middle English" as encompassing English texts up to 1350. This longer time frame would extend the corpus to include many Middle English Romances (especially those of the Auchinleck manuscript c. 1330 ). Gradually, the wealthy and the government Anglicised again, although Norman (and subsequently French ) remained the dominant language of literature and law until
4900-619: The Norse speakers' inability to reproduce the ending sounds of English words influenced Middle English's loss of inflectional endings. Important texts for the reconstruction of the evolution of Middle English out of Old English are the Peterborough Chronicle , which continued to be compiled up to 1154; the Ormulum , a biblical commentary probably composed in Lincolnshire in the second half of
4998-544: The Old English -eþ , Midland dialects showing -en from about 1200, and Northern forms using -es in the third person singular as well as the plural. The past tense of weak verbs was formed by adding an -ed(e) , -d(e) , or -t(e) ending. The past-tense forms, without their personal endings, also served as past participles with past-participle prefixes derived from Old English: i- , y- , and sometimes bi- . Strong verbs , by contrast, formed their past tense by changing their stem vowel (e.g., binden became bound ,
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#17330859319075096-581: The United States, the NFPA definition of a tunnel is "An underground structure with a design length greater than 23 m (75 ft) and a diameter greater than 1,800 millimetres (5.9 ft)." The word "tunnel" comes from the Middle English tonnelle , meaning "a net", derived from Old French tonnel , a diminutive of tonne ("cask"). The modern meaning, referring to an underground passageway, evolved in
5194-400: The blocky nature of rocks, the exact location of fault zones, or the stand-up times of softer ground. This may be a particular concern in large-diameter tunnels. To give more information, a pilot tunnel (or "drift tunnel") may be driven ahead of the main excavation. This smaller tunnel is less likely to collapse catastrophically should unexpected conditions be met, and it can be incorporated into
5292-507: The comparative and superlative (e.g., greet , great; gretter , greater). Adjectives ending in -ly or -lich formed comparatives either with -lier , -liest or -loker , -lokest . A few adjectives also displayed Germanic umlaut in their comparatives and superlatives, such as long , lenger . Other irregular forms were mostly the same as in modern English. Middle English personal pronouns were mostly developed from those of Old English , with
5390-498: The concrete mix to improve lining strength. This creates a natural load-bearing ring, which minimizes the rock's deformation . By special monitoring the NATM method is flexible, even at surprising changes of the geomechanical rock consistency during the tunneling work. The measured rock properties lead to appropriate tools for tunnel strengthening . In pipe jacking , hydraulic jacks are used to push specially made pipes through
5488-478: The development of the Chancery Standard in the 15th century, orthography became relatively standardised in a form based on the East Midlands-influenced speech of London. Spelling at the time was mostly quite regular . (There was a fairly consistent correspondence between letters and sounds.) The irregularity of present-day English orthography is largely due to pronunciation changes that have taken place over
5586-488: The different dialects, that was based chiefly on the speech of the East Midlands but also influenced by that of other regions. The writing of this period, however, continues to reflect a variety of regional forms of English. The Ayenbite of Inwyt , a translation of a French confessional prose work, completed in 1340, is written in a Kentish dialect . The best known writer of Middle English, Geoffrey Chaucer , wrote in
5684-531: The double consonant represented a sound that was (or had previously been) geminated (i.e., had genuinely been "doubled" and would thus have regularly blocked the lengthening of the preceding vowel). In other cases, by analogy, the consonant was written double merely to indicate the lack of lengthening. The basic Old English Latin alphabet consisted of 20 standard letters plus four additional letters: ash ⟨æ⟩ , eth ⟨ð⟩ , thorn ⟨þ⟩ , and wynn ⟨ƿ⟩ . There
5782-468: The end of the Middle English period only the strong -'s ending (variously spelled) was in use. Some formerly feminine nouns, as well as some weak nouns, continued to make their genitive forms with -e or no ending (e.g., fole hoves , horses' hooves), and nouns of relationship ending in -er frequently have no genitive ending (e.g., fader bone , "father's bane"). The strong -(e)s plural form has survived into Modern English. The weak -(e)n form
5880-409: The entire tunnelling process, reducing tunnelling costs. In certain predominantly urban applications, tunnel boring is viewed as a quick and cost-effective alternative to laying surface rails and roads. Expensive compulsory purchase of buildings and land, with potentially lengthy planning inquiries, is eliminated. Disadvantages of TBMs arise from their usually large size – the difficulty of transporting
5978-418: The exception of the third person plural, a borrowing from Old Norse (the original Old English form clashed with the third person singular and was eventually dropped). Also, the nominative form of the feminine third person singular was replaced by a form of the demonstrative that developed into sche (modern she ), but the alternative heyr remained in some areas for a long time. As with nouns, there
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#17330859319076076-441: The final tunnel or used as a backup or emergency escape passage. Alternatively, horizontal boreholes may sometimes be drilled ahead of the advancing tunnel face. Other key geotechnical factors: For water crossings, a tunnel is generally more costly to construct than a bridge. However, both navigational and traffic considerations may limit the use of high bridges or drawbridges intersecting with shipping channels, necessitating
6174-405: The ground behind a TBM or shield. This method is commonly used to create tunnels under existing structures, such as roads or railways. Tunnels constructed by pipe jacking are normally small diameter bores with a maximum size of around 3.2 metres (10 ft). Box jacking is similar to pipe jacking, but instead of jacking tubes, a box-shaped tunnel is used. Jacked boxes can be a much larger span than
6272-587: The immersed-tube type), while deep tunnels are excavated, often using a tunnelling shield . For intermediate levels, both methods are possible. Large cut-and-cover boxes are often used for underground metro stations, such as Canary Wharf tube station in London. This construction form generally has two levels, which allows economical arrangements for ticket hall, station platforms, passenger access and emergency egress, ventilation and smoke control, staff rooms, and equipment rooms. The interior of Canary Wharf station has been likened to an underground cathedral, owing to
6370-412: The indicator of the longer and changed pronunciation of ⟨a⟩ . In fact, vowels could have this lengthened and modified pronunciation in various positions, particularly before a single consonant letter and another vowel or before certain pairs of consonants. A related convention involved the doubling of consonant letters to show that the preceding vowel was not to be lengthened. In some cases,
6468-435: The inevitable smoke and steam. A major disadvantage of cut-and-cover is the widespread disruption generated at the surface level during construction. This, and the availability of electric traction, brought about London Underground's switch to bored tunnels at a deeper level towards the end of the 19th century. Prior to the replacement of manual excavation by the use of boring machines, Victorian tunnel excavators developed
6566-565: The lack of written evidence from the areas of Danish control, as the majority of written sources from Old English were produced in the West Saxon dialect spoken in Wessex , the heart of Anglo-Saxon political power at the time. The Norman Conquest of England in 1066 saw the replacement of the top levels of the English-speaking political and ecclesiastical hierarchies by Norman rulers who spoke
6664-760: The language of government and law can be seen in the abundance of Modern English words for the mechanisms of government that are derived from Anglo-Norman, such as court , judge , jury , appeal , and parliament . There are also many Norman-derived terms relating to the chivalric cultures that arose in the 12th century, an era of feudalism , seigneurialism , and crusading . Words were often taken from Latin, usually through French transmission. This gave rise to various synonyms, including kingly (inherited from Old English), royal (from French, inherited from Vulgar Latin), and regal (from French, which borrowed it from Classical Latin). Later French appropriations were derived from standard, rather than Norman, French. Examples of
6762-468: The large TBM to the site of tunnel construction, or (alternatively) the high cost of assembling the TBM on-site, often within the confines of the tunnel being constructed. There are a variety of TBM designs that can operate in a variety of conditions, from hard rock to soft water-bearing ground. Some TBMs, the bentonite slurry and earth-pressure balance types, have pressurized compartments at the front end, allowing them to be used in difficult conditions below
6860-403: The later Middle English period began to undergo the Great Vowel Shift . Little survives of early Middle English literature , due in part to Norman domination and the prestige that came with writing in French rather than English. During the 14th century, a new style of literature emerged with the works of writers including John Wycliffe and Geoffrey Chaucer , whose Canterbury Tales remains
6958-969: The length. A pipeline differs significantly from a tunnel, though some recent tunnels have used immersed tube construction techniques rather than traditional tunnel boring methods. A tunnel may be for foot or vehicular road traffic , for rail traffic, or for a canal . The central portions of a rapid transit network are usually in the tunnel. Some tunnels are used as sewers or aqueducts to supply water for consumption or for hydroelectric stations. Utility tunnels are used for routing steam, chilled water, electrical power or telecommunication cables, as well as connecting buildings for convenient passage of people and equipment. Secret tunnels are built for military purposes, or by civilians for smuggling of weapons , contraband , or people . Special tunnels, such as wildlife crossings , are built to allow wildlife to cross human-made barriers safely. Tunnels can be connected together in tunnel networks . A tunnel
7056-607: The lower deck with automobiles above, now converted to one-way road vehicle traffic on each deck. In Turkey, the Eurasia Tunnel under the Bosphorus , opened in 2016, has at its core a 5.4 km (3.4 miles) two-deck road tunnel with two lanes on each deck. Additionally, in 2015 the Turkish government announced that it will build three -level tunnel, also under the Bosporus. The tunnel
7154-417: The masculine accusative, genitive, and dative, the feminine dative, and the plural genitive. The Owl and the Nightingale adds a final -e to all adjectives not in the nominative, here only inflecting adjectives in the weak declension (as described above). Comparatives and superlatives were usually formed by adding -er and -est . Adjectives with long vowels sometimes shortened these vowels in
7252-427: The more complex system of inflection in Old English : Nouns of the weak declension are primarily inherited from Old English n -stem nouns but also from ō -stem, wō -stem, and u -stem nouns, which did not inflect in the same way as n -stem nouns in Old English, but joined the weak declension in Middle English. Nouns of the strong declension are inherited from the other Old English noun stem classes. Some nouns of
7350-454: The most studied and read work of the period. The transition from Late Old English to Early Middle English had taken place by the 1150s to 1180s, the period when the Augustinian canon Orrm wrote the Ormulum , one of the oldest surviving texts in Middle English. The influence of Old Norse aided the development of English from a synthetic language with relatively free word order to
7448-681: The old insular g and the Carolingian g (modern g ), the former continued in use as a separate letter, known as yogh , written ⟨ȝ⟩ . This was adopted for use to represent a variety of sounds: [ɣ], [j], [dʒ], [x], [ç] , while the Carolingian g was normally used for [g]. Instances of yogh were eventually replaced by ⟨j⟩ or ⟨y⟩ and by ⟨gh⟩ in words like night and laugh . In Middle Scots , yogh became indistinguishable from cursive z , and printers tended to use ⟨z⟩ when yogh
7546-483: The older method of tunnelling in compressed air, with an airlock/decompression chamber some way back from the TBM, which required operators to work in high pressure and go through decompression procedures at the end of their shifts, much like deep-sea divers . In February 2010, Aker Wirth delivered a TBM to Switzerland, for the expansion of the Linth–Limmern Power Stations located south of Linthal in
7644-540: The operation of empty and loaded trains at the same time. The temporary way is replaced by the permanent way at completion, thus explaining the term " Perway ". The vehicles or traffic using a tunnel can outgrow it, requiring replacement or enlargement: An open building pit consists of a horizontal and a vertical boundary that keeps groundwater and soil out of the pit. There are several potential alternatives and combinations for (horizontal and vertical) building pit boundaries. The most important difference with cut-and-cover
7742-423: The other case endings disappeared in the Early Middle English period, including most of the roughly one dozen forms of the definite article ("the"). The dual personal pronouns (denoting exactly two) also disappeared from English during this period. The loss of case endings was part of a general trend from inflections to fixed word order that also occurred in other Germanic languages (though more slowly and to
7840-510: The period in Scandinavia and Northern England do not provide certain evidence of an influence on syntax. However, at least one scholarly study of this influence shows that Old English may have been replaced entirely by Norse, by virtue of the change from Old English to Norse syntax. While the Old Norse influence was strongest in the dialects under Danish control that composed the southern part of
7938-510: The project is completed. If a tunnel is going to be long, multiple shafts at various locations may be bored so that entrance to the tunnel is closer to the unexcavated area. Once construction is complete, construction access shafts are often used as ventilation shafts , and may also be used as emergency exits. The New Austrian Tunnelling method (NATM)—also referred to as the Sequential Excavation Method (SEM) —was developed in
8036-485: The proper machinery must be selected. Large infrastructure projects require millions or even billions of dollars, involving long-term financing, usually through issuance of bonds . The costs and benefits for an infrastructure such as a tunnel must be identified. Political disputes can occur, as in 2005 when the US House of Representatives approved a $ 100 million federal grant to build a tunnel under New York Harbor. However,
8134-564: The resulting doublet pairs include warden (from Norman) and guardian (from later French; both share a common ancestor loaned from Germanic). The end of Anglo-Saxon rule did not result in immediate changes to the language. The general population would have spoken the same dialects as they had before the Conquest. Once the writing of Old English came to an end, Middle English had no standard language, only dialects that evolved individually from Old English. Early Middle English (1150–1350) has
8232-482: The risk of encountering unforeseen ground conditions. In planning the route, the horizontal and vertical alignments can be selected to make use of the best ground and water conditions. It is common practice to locate a tunnel deeper than otherwise would be required, in order to excavate through solid rock or other material that is easier to support during construction. Conventional desk and preliminary site studies may yield insufficient information to assess such factors as
8330-736: The second half of the 14th century in the emerging London dialect, although he also portrays some of his characters as speaking in northern dialects, as in " The Reeve's Tale ". In the English-speaking areas of lowland Scotland , an independent standard was developing, based on the Northumbrian dialect . This would develop into what came to be known as the Scots language . A large number of terms for abstract concepts were adopted directly from scholastic philosophical Latin (rather than via French). Examples are "absolute", "act", "demonstration", and "probable". The Chancery Standard of written English emerged c. 1430 in official documents that, since
8428-458: The second person singular in -(e)st (e.g., þou spekest , "thou speakest"), and the third person singular in -eþ (e.g., he comeþ , "he cometh/he comes"). ( þ (the letter "thorn") is pronounced like the unvoiced th in "think", but under certain circumstances, it may be like the voiced th in "that"). The following table illustrates a typical conjugation pattern: Plural forms vary strongly by dialect, with Southern dialects preserving
8526-528: The sheer size of the excavation. This contrasts with many traditional stations on London Underground , where bored tunnels were used for stations and passenger access. Nevertheless, the original parts of the London Underground network, the Metropolitan and District Railways, were constructed using cut-and-cover. These lines pre-dated electric traction and the proximity to the surface was useful to ventilate
8624-435: The side of the road. The two tunnels are linked by escape cross-passages at intervals of 100 to 130 metres (330–430 ft). Tunnel A tunnel is an underground or undersea passageway. It is dug through surrounding soil, earth or rock, or laid under water, and is usually completely enclosed except for the two portals common at each end, though there may be access and ventilation openings at various points along
8722-409: The strong type have an -e in the nominative/accusative singular, like the weak declension, but otherwise strong endings. Often, these are the same nouns that had an -e in the nominative/accusative singular of Old English (they, in turn, were inherited from Proto-Germanic ja -stem and i -stem nouns). The distinct dative case was lost in early Middle English, and although the genitive survived, by
8820-400: The tunnel drive, the depth of the tunnel, the logistics of supporting the tunnel excavation, the final use and the shape of the tunnel and appropriate risk management. There are three basic types of tunnel construction in common use. Cut-and-cover tunnels are constructed in a shallow trench and then covered over. Bored tunnels are constructed in situ, without removing the ground above. Finally,
8918-428: The two most common being bored tunnels or immersed tubes , examples are Bjørvika Tunnel and Marmaray . Submerged floating tunnels are a novel approach under consideration; however, no such tunnels have been constructed to date. During construction of a tunnel it is often convenient to install a temporary railway, particularly to remove excavated spoil , often narrow gauge so that it can be double track to allow
9016-566: Was constructed to provide a second harbour crossing and to alleviate traffic congestion on the Sydney Harbour Bridge , without spoiling the iconic view. Other reasons for choosing a tunnel instead of a bridge include avoiding difficulties with tides, weather, and shipping during construction (as in the 51.5-kilometre or 32.0-mile Channel Tunnel ), aesthetic reasons (preserving the above-ground view, landscape, and scenery), and also for weight capacity reasons (it may be more feasible to build
9114-425: Was indicated by agreement of articles and pronouns (e.g., þo ule "the feminine owl") or using the pronoun he to refer to masculine nouns such as helm ("helmet"), or phrases such as scaft stærcne (strong shaft), with the masculine accusative adjective ending -ne . Single-syllable adjectives added -e when modifying a noun in the plural and when used after the definite article ( þe ), after
9212-520: Was not yet a distinct j , v , or w , and Old English scribes did not generally use k , q , or z . Ash was no longer required in Middle English, as the Old English vowel /æ/ that it represented had merged into /a/ . The symbol nonetheless came to be used as a ligature for the digraph ⟨ae⟩ in many words of Greek or Latin origin, as did ⟨œ⟩ for ⟨oe⟩ . Eth and thorn both represented /θ/ or its allophone / ð / in Old English. Eth fell out of use during
9310-417: Was ousted by it in most dialects by the 15th. The following table shows some of the various Middle English pronouns. Many other variations are noted in Middle English sources because of differences in spellings and pronunciations at different times and in different dialects. As a general rule, the indicative first person singular of verbs in the present tense ended in -e (e.g., ich here , "I hear"),
9408-469: Was some inflectional simplification (the distinct Old English dual forms were lost), but pronouns, unlike nouns, retained distinct nominative and accusative forms. Third person pronouns also retained a distinction between accusative and dative forms, but that was gradually lost: The masculine hine was replaced by him south of the River Thames by the early 14th century, and the neuter dative him
9506-411: Was substantive, pervasive, and of a democratic character. Like close cousins, Old Norse and Old English resembled each other, and with some words and grammatical structures in common, speakers of each language roughly understood each other, but according to historian Simeon Potler the main difference lied on their inflectional endings, which led to much confusion within the mixed population that existed in
9604-701: Was superseded by the Madrid M30 ringroad , Spain, and the Chong Ming tunnels in Shanghai , China. All of these machines were built at least partly by Herrenknecht . As of August 2013 , the world's largest TBM was " Big Bertha ", a 17.5-metre (57.5 ft) diameter machine built by Hitachi Zosen Corporation , which dug the Alaskan Way Viaduct replacement tunnel in Seattle, Washington (US). A temporary access shaft
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