How the world's longest underwater tunnel was built - Alex Gendler

Prevodilac: Aleksandar Bošnjak Lektor: Ivana Korom

Flanked by two powerful European nations, the English Channel

Okružen sa dve moćne evropske nacije, Engleski kanal ili Lamanš

has long been one of the world’s most important maritime passages.

je oduvek bio jedan od svetki važnijih pomorskih prolaza.

Yet for most of its history,

A ipak, većinu istorije

the channel’s rocky shores and stormy weather

kamenite obale i nevremena u oblasti kanala

made crossing a dangerous prospect.

su načinile prelazak opasnim izazovom.

Engineers of the early 1800's proposed numerous plans

Inženjeri ranih 1800. godina su predlagali brojne planove

for spanning the 33 kilometer gap.

za prelazak preko međuprostora od 33 kilometara.

Their designs included artificial islands linked by bridges,

Dizajn je uključivao veštačka ostrva koja su povezana mostovima,

submerged tubes suspended from floating platforms,

potopljene cevi koje su obešene na plutajuće platforme

and an underwater passage more than twice the length of any existing tunnel.

i podvodni prolaz koji je bio duplo duži od bilo kog postojećeg tunela.

By the end of the century,

Krajem veka,

this last proposal had captured European imagination.

ovaj poslednji predlog je zagolicao evropsku maštu.

The invention of the tunnel boring machine

Pronalaskom mašine za bušenje tunela

and the discovery of a stable layer of chalk marl below the seabed

i otkrića stabilnog sloja krede lapora ispod morskog dna

made this fantastic tunnel more feasible.

načinilo je ovaj fantastčni tunel izvodljivijim.

But the project’s most urgent obstacles were ones no engineer could solve.

Ali najhitnije prepreke projekta nijedan inženjer nije mogao da reši.

At the time,

U to vreme,

Britons viewed their geographic isolation as a strategic advantage,

Britanci su smatrali geografsku izolaciju kao strategijsku prednost,

and fears about French invasion shut down plans for the tunnel.

a strahovi od invazije Francuza su ugasili planove za tunelom.

The rise of aerial warfare rendered these worries obsolete,

Porasti vazdušnih napada su načinili ove brige zastarelim,

but new economic concerns arose to replace them.

a iznikli su novi ekonomski interesi umesto njih.

Finally, 100 years after the initial excavation,

Naposletku, 100 godina nakon prvog iskopavanja,

the two countries reached an agreement—

ove dve države su postigle dogovor,

the tunnel would proceed with private funding.

iskopavanje tunela će se nastaviti privatnim finansiranjem.

In 1985, a group of French and British companies

1985. godine, grupa francuskih i britanskih kompanija

invested the modern equivalent of 14 billion pounds,

je investirala približno današnjih 17,5 milijardi dolara,

making the tunnel the most expensive infrastructure project to date.

čineći tunel najskupljim infrastrukturnim projektom do danas.

The design called for three separate tunnels—

Dizajn je zahtevao tri odvojena tunela,

one for trains to France, one for trains to England,

jedan za vozove ka Francuskoj, jedan za vozove ka Engleskoj,

and one service tunnel between them.

i jedan uslužni tunel između njih.

Alongside crossover chambers, emergency passages, and air ducts,

Pored stanica za presedanje, izlaza u slučaju opasnosti i vazdušnih kanala,

this amounted to over 200 kilometers of tunnels.

ovo sve zajendo broji preko 200 kilomerara tunela.

In 1988, workers began excavating from both sides,

1988. godine, radnici su počeli iskopavanje sa obe strane,

planning to meet in the middle.

planirajući da se sretnu u sredini.

Early surveys of the French coast revealed the site was full of fault lines.

Rani pregledi francuske obale su otkrili da je položaj bio pun raseda.

These small cracks let water seep into the rock,

Te male pukotine su propuštale po malo vode u kamen,

so engineers had to develop waterproof boring machines.

tako da su inženjeri morali da razviju vodootporne mašine za bušotine.

The British anticipated drier conditions, and forged ahead with regular borers.

Britanci su očekivali suvije uslove, pa su nastavili sa regularnim mašinama.

But only months into the work, water flooded in through undetected fissures.

Ali samo nekoliko meseci kasnije, voda je prošla kroz neotkrivene pukotine.

To drill in this wet chalk, the British had to use grout

Kako bi bušili ovaj mokri kreč, Britanci su morali da koriste fugirne mase

to seal the cracks created in the borer’s wake,

kako bi zatvorili pukotine koje su nastale zbog bušenja,

and even work ahead of the main borer

čak su i morali da koriste ovo pre glavne bušilice.

to reinforce the chalk about to be drilled.

kako bi ojačali kreč koji tek treba da se buši.

With these obstacles behind them, both teams began drilling at full speed.

Sa ovim preprekama iza njih, oba tima su počela da buše punom brzinom.

Boring machines weighing up to 1,300 tons drilled at nearly 3.5 meters per hour.

Mašine za bušotine su teške do 1,300 tona i buše skoro 3,5 metra po satu.

As they dug, they installed lining rings to stabilize the tunnel behind them,

Dok su iskopavali, postavljali su ojačanja kako bi stabilizovali tunel iza nih,

making way for support wagons following each machine.

praveći put za pomoćne vagone koji su pratili svaku mašinu.

Even at top speed, work had to proceed carefully.

Čak i pri najvećoj brzini, posao je morao da se odvija pažljivo.

The chalk layer followed a winding path between unstable rock and clay,

Sloj kreča pratio je vijugav put između nestabilnog kamena i gline,

punctured by over 100 boring holes made by previous surveyors.

koji su prethodni geodeti probušili sa više od 100 rupa.

Furthermore, both teams had to constantly check their coordinates

Štaviše, oba tima su stalno morala da proveravaju svoje koordinate

to ensure they were on track to meet within 2 centimeters of each other.

da bi bili sigurni da će se sresti dva centimetara jedan od drugog.

To maintain this delicate trajectory,

Kako bi se ova delikatna putanja održala,

the borers employed satellite positioning systems,

bušači su uposlili satelitske sisteme za pozicioniranje,

as well as paleontologists who used excavated fossils

kao i paleontologe koji su koristili iskopane fosile

to confirm they were at the right depth.

da portvrde da su na tačnoj dubini.

During construction, the project employed over 13,000 people

Tokom izgradnje, projekat je uposlio preko 13,000 ljudi

and cost the lives of ten workers.

i koštao je života deset radnika.

But after two and a half years of tunneling,

A nakon dve i po godine kopanja tunela,

the two sides finally made contact.

dve strane su napokon ostvarile kontakt.

British worker Graham Fagg emerged on the French side,

Britanski radnik Graham Feg se pojavio na francuskoj strani,

becoming the first human to cross the channel by land since the Ice Age.

postavši prvi čovek koji je prešao kanal putem zemlje još od ledenog doba.

There was still work to be done—

Još je bilo posla,

from installing crossover chambers and pumping stations,

od postavljanja stanica za presedanje i crpnih stanica,

to laying over a hundred miles of tracks, cables, and sensors.

preko postavljanja pruga, kablova i senzora.

But on May 6, 1994, an opening ceremony marked the tunnel’s completion.

6. maja 1994. godine ceremonija otvaranja je označila završetak tunela.

Full public service began 16 months later,

Javnost je u potpunosti krenula da koristi ovaj tunel 16 meseci kasnije,

with trains for passengers and rail shuttles for cars and trucks.

sa vozovima za putnike i vagonima za automobile i kamione.

Today, the Channel Tunnel services over 20 million passengers a year,

Danas, evrotunel opslužuje preko 20 miliona putnika godišnje,

transporting riders across the channel in just 35 minutes.

prevozeći ljude preko tunela za samo 35 minuta.

Unfortunately, not everyone has the privilege of making this trip legally.

Nažalost, nemaju svi privilegiju da legalno koriste ove usluge.

Thousands of refugees have tried to enter Britain through the tunnel

Hiljade izbeglica je pokušalo da uđe u Britaniju kroz tunel

in sometimes fatal attempts.

sa ponekad fatalnim ishodima.

These tragedies have transformed the tunnel’s southern entrance

Ove tragedije su pretvorile južni ulaz u tunel

into an ongoing site of conflict.

u neprekidno mesto konflikta.

Hopefully, the structure’s history can serve as a reminder

Nadajmo se da istorija tunela može da posluži kao podsetnik

that humanity is at their best when breaking down barriers.

da je čovečanstvo najuspešnije kada ruši barijere.