After many centuries of mistrust, leading at times to military conflicts, the French and British were finally united ... by a common dislike of seasickness. The water element that has separated the UK from France over the past 8,000 years is very capricious and has often made the ferry crossing an ordeal for passengers.
However unshakable faith British Empire until recently, the need to preserve this semblance of a gigantic fortress moat forced travelers to choose an air route or to swim, painfully hanging overboard. Britain's accession to the European Union marked the beginning of a new relationship between old rival neighbors. In an impulse to overcome all obstacles on the way to the unity of the country, they began to develop a project that would forever tie their shores. There were various proposals: the construction of a tunnel, a bridge, a combination of both. In the end, the tunnel won.
The main argument in favor of this decision was the information received from geologists. They found out that under water the two countries are already connected by a layer of chalky-chalky rock. This soft limestone rock was excellent for tunnel construction: it is quite easy to mine, has a high natural stability and water resistance. The multitude of wells drilled at the bottom of the English Channel and advanced acoustic sounding technology gave geologists the opportunity to obtain sufficiently accurate data on the underwater relief of the strait and geological structure its bottom. Using this information, the engineers decided on the route of the tunnel.
To better control traffic, as well as to avoid the huge ventilation problems that are bound to arise in a 39-kilometer car tunnel, engineers opted for a railway tunnel. Now, instead of a ferry, cars and trucks call into special freight trains that ferry them to the other side of the strait. Regardless of the weather, the crossing from terminal to terminal takes 35 minutes, of which only 26 are to be spent in the tunnel. Another train called Eurostar transports passengers from central London to the center of either Paris or Brussels in a little over three hours.
One of the greatest structures of the 20th century, the Channel Tunnel, is actually a complex system of three "galleries" that run parallel to each other. Trains go from England to France along the northern tunnel, and back along the southern one. There is a narrow technical tunnel between them, the main function of which is to provide access to the working tunnels for maintenance. It is also designed to evacuate passengers. A high air pressure is maintained in the technical tunnel to prevent smoke or flames from entering if there is a fire in one of the main tunnels.
All three tunnels are connected by small passages located along the entire length of the structure at a distance of approximately 365 meters from each other. Two transport tunnels are interconnected every 244 meters by air locks. Thanks to the sluices, the air pressure generated under the pressure of the moving train is neutralized: the air in front of the train, without causing any damage to the train, goes through them into another transport tunnel. This reduces the so-called piston effect.
By this time, tunneling was carried out using special drilling rigs - tunnel boring complexes, or TPK. These are almost fully automated devices, a modern, high-tech version of the Greathead's shield. Punching the tunnel, TPK leaves behind an almost complete structure - a cylindrical tunnel sheathed with concrete lining. In front of each TPK there is a working unit. It consists of a rotating rotor, literally "cutting" the rock.
The rotor is forcefully pressed against the bottomhole surface by a ring of hydraulic cylinders, which also direct its movement. There are spacer cylinders directly behind the drill head. They press giant spacer plates against the walls, resting against which they repel the cylinders and the rotor. A dispatching console is located behind the working unit, from where the operator of the TPK monitors the progress of the drill head. Thanks to the laser navigation system, the complex absolutely precisely adheres to the given direction.
The largest TPK rotor has a diameter of about 9 meters and rotates at a speed of two to three revolutions per minute. The rotor is reinforced with chisel-shaped pointed teeth, or with steel disc nozzles, or a combination of both. Rotating, the rotor carves concentric circles in the chalk-limestone. At a certain depth, the cut rock gives cracks and splits. Broken-off pieces fall onto a conveyor that transfers the waste rock to the trolleys already waiting for it at the tail of the tunneling complex.
The last element of the TPK to be mentioned is the mechanical lining stacker.
He installs lining segments on the tunnel walls. For the working TPK, the technical staff stretches for 240 meters. It delivers lining segments, transports waste rock, supplies fresh air, water, electricity, providing workers with everything they need "on the job."
So, the construction of the Channel Tunnel began with the construction of entrance shafts on both sides of the strait. Eleven TPKs and other equipment were lowered into them. After assembly, six TPKs, three each from England and France, began their journey under the strait, hoping to meet safely under the water column in the middle of the strait. The other five worked on land, shaping the entrance areas of the future tunnel. The first builders planned to break through a technical tunnel - it was supposed to become a kind of "forward landing" in the general system.
However, even with an arsenal of cutting-edge technical means when the Eurotunnel was pierced, not everything went according to plan. To begin with, the British TPKs were designed to work only in "dry" faces. Needless to say, when, somewhere in the middle of the drift, the bottomhole began to fill in through cracks in the rock salty water, the builders had a very difficult time. The WPK on the British side of the working tunnel had to be stopped. Engineers were urgently deciding how to stop the flow of water. As a result, they built something like a giant concrete "umbrella", which prevented the tunnel from flooding. It took months to pump the grout into the resulting fractures. Then the ceiling of the tunnel above the TPK was dismantled and sheathed with steel panels, a thin layer of shotcrete was applied to them. Only after that did the work on the British side continue.
All three tunnels are covered with a circular concrete lining, which consists of separate segments. The segment "closing" each ring is smaller in size than the others and has a wedge-shaped shape. This shape subtly reminds us that this modern structure belongs to the oldest family of arches. Most of the lining segments are cast from reinforced concrete, with the exception of those installed in the transition tunnels and air vents - they are made of cast iron.
In October 1990, when the two parts of the technical tunnel under construction were separated by a little more than 90 meters, the TPK was stopped. To make sure that both halves of the tunnel are in line, a probe borehole with a diameter of 5 centimeters was drilled from the English side. When she reached the "French" part of the tunnel, a narrow connecting corridor was manually cut between them. Then it was expanded to the required diameter with small miners. Six months later, the main tunnels also connected. The work ended with a very interesting operation from a technical point of view. Instead of spending energy and money on dismantling and retrieving their drill heads to the surface, British engineers simply sent them down, and the mechanisms themselves dug their last refuge. When the drilling equipment disappeared into the ground, and the formed depressions were poured with concrete, French TPKs passed over them into the English part of the tunnels.
When building any tunnel - especially when it comes to a giant 50 kilometers long - you should carefully plan how the waste soil will be extracted and disposed of. For this purpose, the far-sighted British built a huge dam, which fenced off several sea lagoons near the entrance shafts of the tunnel. The waste soil was lifted up and poured into these lakes. Drying up, they expanded the UK by several hundred square meters. The French were less fortunate - they had to deal with much more soil. They mixed it with water and pumped it into a lake located 2.5 kilometers from the coast. When the lake dried up, the resulting patch of land was sown with grass. The area of the country, alas, has remained the same, but one green corner has become more.
To ensure the uninterrupted movement of trains 24 hours a day, even if part of the route has to be temporarily closed, two intersecting crossings were built in the main tunnels, they are also called passing cameras. They are located about a third of the way from each shore. Thanks to them, the train can always go around the blocked section in another tunnel, and at the next junction return to the original track. This, of course, slows down the movement somewhat, but under any circumstances, except in the most extreme cases, the Channel Tunnel will work!
The passing chambers were built very large - about 150 meters long, 20 meters wide and 15 meters high each. To strengthen their structure, the rock around the passing chambers was strengthened with shotcrete and 4-6 meter steel rods - anchor bolts.
During the construction of the chambers, the workers installed measuring devices in the chalk rock to monitor the condition of the soil. If a problem was found, the thickness of the sheathing or the length of the anchor bolts were increased. During construction work, communication with the cameras was carried out through a technical tunnel: all the necessary materials and equipment were delivered through it and the waste soil was removed.
Massive shutters were installed in the completed passage chambers. They must prevent the spread of fire in a fire, they are also used to independently supply air to each of the tunnels. The gates open only when it is necessary to use the siding.
After all the tunnels were completely pierced, the work continued for another two years. Workers pulled miles of cables for security systems, signaling, lighting and pumping equipment. Two pipes were installed, through which chilled water was constantly supplied, in order to reduce the air temperature in the tunnel, which increases due to the movement of high-speed trains. All equipment, including the trains themselves, has been tested many times.
By the end of 1993, the construction of the Eurotunnel was completed. And in May next year, this most expensive engineering facility in the history of mankind began to work.
David Macauley. How it's built: from bridges to skyscrapers.
American Society of Civil Engineers ( American Society of Civil Engineers) declared the Eurotunnel one of the seven wonders of the world of our time.
History of origin
Sketch by Albert Mathieu-Favier
The idea of building a tunnel under the English Channel arose in the late 18th - early 19th centuries.
According to the project, the tunnel was supposed to connect two cities - Calais on the French side and Folkestone on the English side (this path is longer than the shortest possible). It was supposed to dig in the easily pliable chalk geological layer, so the tunnel had to run deeper than planned - about 50 meters below the bottom of the strait, and South part should run deeper than the northern one. Because of this, the French first had to build a mine with a diameter of 50 m and a depth of 60 m in order to reach the sandstone.
Construction
The main contractor for the construction of the tunnel was the Anglo-French consortium TransManche Link, consisting of ten construction companies and five investment banks from both participating countries. For the construction of the tunnel, 11 special tunneling shields with a rotor diameter of 8 meters were developed. During operation, the rotor rotated at a frequency of 2-3 revolutions per minute.
Safety system
Eurotunnel section. Eurotunnel Shuttle, Service Train in Service Tunnel and Eurostar are shown
The Eurotunnel consists of three tunnels - two main ones with a track for trains going north and south, and one small service tunnel. The service tunnel has passages every 375 meters that connect it with the main ones. It is designed for access to the main tunnels for service personnel and emergency evacuation of people in case of danger.
Every 250 meters, both main tunnels are connected to each other by a special ventilation system located on top of the service tunnel. This airlock system negates the piston effect generated by moving trains by distributing the air flow to the adjacent tunnel.
All three tunnels have two junctions allowing trains to move freely between the tunnels.
Right-hand traffic of trains is organized in the tunnel.
The Eurotunnel security system has been tested four times.
All victims subsequently fully recovered. There were no casualties, mainly due to the construction of the tunnel and the coordinated work of the security services of France and Great Britain.
It seems that the French and British have a penchant for long-term joint projects. There are more than enough examples in history: The Hundred Years War, which they entered into in 1337, stretched for 116 years, a project to create supersonic aircraft The Concorde took two decades to complete. And one of the most ambitious construction projects of the twentieth century - a tunnel under the English Channel - started back in 1881. Then the matter did not move further than the station facilities, but now many do not understand how they even managed to get to the British Isles when there was no tunnel.
The British have always been proud and continue to be proud of their isolation from the rest of Europe. They did not switch to the euro, did not join the European Union. The English approach to integration is well characterized by history dating back to 1858. That year, for the first time, the question of building a tunnel across the English Channel was raised in the Parliament of England. Hearing this, Lord Palmerston, at that time the Prime Minister of Great Britain, was indignant: “What? Do you dare to ask for money for a business whose purpose is to shorten the distance, as we believe, is already too short? " Against this background, it seems surprising how the inhabitants of Albion in general decided to lay a tunnel to continental Europe. However, no less striking is the persistence with which the French and British engineers proposed projects for the land connection of the two states: in the period from 1883 to 1941 alone, more than 300 (!) Various projects of bridges and tunnels were presented.
In the middle of the 19th century, steamboats transported 350 thousand passengers across the English Channel, and there were three Britons for one "continental" European. French engineer Thomay de Gamon was convinced that his tunnel would double passenger traffic - mainly due to the influx of tourists from continental Europe, many of whom do not like to travel on water due to seasickness.
Underground cavalry
The idea of establishing a land connection between the continent and the British Isles was born in the middle of the 18th century, when the University of Amiens announced a competition for the best project to connect the two states. The first real project of the tunnel dates back to 1802. It was developed by Albert Mathieu. The Frenchman proposed to lay a tunnel for the movement of horse-drawn carriages at a depth of about 10 meters from the bottom of the strait, illuminate it with oil lamps, and use special shafts for ventilation, which were supposed to rise five meters above the water surface. It is known that Napoleon was familiar with the Mathieu project. Did he interest him? History stores exactly the opposite information. According to one version, the tunnel seemed to Napoleon a delusional undertaking. According to another, he personally offered the British to connect their countries by an underground road.
International Metro
With the rapid development of the railway network in England, the equestrian versions of the tunnel were replaced by rail ones. In the 19th century, the French mining engineer Thomé de Gamon became the main guardian of such projects. It is known that the Frenchman so fanatically wanted to connect the continent with the island that he spent more than 30 years carefully working out seven alternative projects. Among them was such an extravagant version of the connection as a giant bridge, leaning on bulk islands... In 1860 new project de Gamon's tunnel was approved by Napoleon III and Queen Victoria, but the Frenchman's dream did not come true - it did not come to construction.
One of the projects of Thomay de Gamon - the main enthusiast of the construction of the land link between France and Britain in the 19th century. The project was approved, but it never came to construction
In the 1870s, relations between the French and the British warmed dramatically. After the defeat in the Franco-Prussian War, the French invited the British to rally to oppose a new powerful enemy - the German Kaiser. The neighbors began to re-develop the tunnel project.
Engineers from the Victorian era made great strides in tunneling. In 1843, they were the first in the world to tunnel under the Thames with a tunneling shield, and then gained tremendous experience in this area when building the world's first London Underground. Therefore, technically, the construction of a tunnel under the English Channel was not a big problem. In 1881, two tunneling shields of the company “ Beaumont & English"- the most powerful and technically advanced at the time. In the first year, about 2 km of track were dug on both sides: it was expected that the underground meeting of the workers would take place in five years. However, in 1883, the construction of a tunnel under the English Channel was stopped. British politicians and journalists increasingly came out with statements that the tunnel would be an excellent gift for their potential enemy - in the event of a conflict, the French could easily attack Britain through the tunnel. Until World War II, all projects of tunnels or bridges across the English Channel met with harsh opposition from the British government. The attitude towards the project changed only in the mid-1950s.
The tunnel is not so terrible ...
When the Second ended World War, it became obvious that with the advent of new types of transport and weapons, the tunnel no longer poses a real threat to the UK's defenses. This was publicly announced by the UK Department of Defense in 1955. The exchange of goods between the island and the continent, meanwhile, steadily increased. Therefore, in the summer of 1957, an Anglo-French research group was formed, which was to find out whether it was necessary to connect the two states and, if so, how. By the early 1960s, two alternatives were competing - the tunnel design and the bridge design. According to the first project, it was supposed to lay a complex railway tunnel under the bottom of the strait, consisting of two working sleeves and a service one between them. This project was competing with the project of a giant bridge, warmly supported by the leaders of metallurgical concerns. In the end, the underground project won, but the approval process was delayed. After the construction of the tunnel began in 1974, funding problems arose. A year later, the project was suspended.
They returned to the topic of the tunnel only in 1984, when the governments of the two countries announced an open tender for a project that would connect the UK with France. In the fall of 1985, four independent development groups came up with their own options.
The most extravagant was the project Europont- 52 km bridge with spans suspended on kevlar threads. The project was quickly dismissed as too expensive and based on as yet untested technology. Another project - Euroroute- offered a complex system of bridges and tunnels with anchor points on purpose-built artificial islands.
Option EuroRoute was considered the main competitor of the winning project. According to him, it was planned to dig a railway tunnel across the entire strait, and to use two bridges and a 21-kilometer tunnel for traffic. To enter the autotunnel from a bridge in the strait, two artificial islands were to be built, and a third one for the ventilation shaft.
Project Channel Expressway was a two-level tunnel with rail and road connections. Both of these projects preferred Eurotunnel Is the cheapest and easiest to build alternative, based on the 1970s tunnel concept. According to preliminary estimates of the developers, the implementation of the project Eurotunnel was estimated at 5 billion pounds.
Project outline Eurotunnel
However, even this amount seemed too high for the governments of both European countries: in January 1986, Margaret Thatcher and François Mitterrand jointly announced that they considered the project too expensive an undertaking to spend on taxpayers' money.
Rails against freeway
Project Channel Expressway lost to the project Eurotunnel not only because of the higher cost. It was decided that driving a car through a 50-kilometer tunnel would require a lot of physical and mental stress from drivers, which could lead to stressful situations and accidents. In addition, the issue of cleaning the tunnel from exhaust gases required a more efficient solution. The most preferred option is the transportation of cars on electric train platforms.
But such a statement did not mean that the project was postponed again. A way out was found. We decided to organize an open joint stock company " Eurotunnel», The initial capital of which was to be provided by construction companies with the support of private banks (without state support). The newly formed company had to independently find money for the construction of the tunnel - including through the sale of its shares. As a token of gratitude, she received the right to manage the structure for 55 years. At the end of this period, the tunnel in working order must be handed over to the governments of France and Great Britain.
New story
The further fate of the tunnel across the English Channel is well known. On December 15, 1987, the first tunneling shield was put into operation - it dug a service tunnel with a diameter of 4.8 m. Then more powerful roadheaders joined the business, which laid two main tunnels with a diameter of 7.6 m each. In total, 11 shields worked simultaneously in the depth of the tunnel practically without interruption. Three French and three English shields were moving towards each other under the English Channel. Three more were tunneling deep into the island towards the British terminal, and two were drilling three tunnels towards the French terminal. Directly at the bottom of the sea, 39 km of the tunnel was dug, and its total length was 51 km.
The entrances to the tunnel are located at a distance of 3.7 km from the strait on the French coast and 9.8 km - on English territory. The maximum height of the water layer above the tunnel at high tide is 60 m
In order for both ends to meet in one place, a laser positioning system was used. Thanks to her, workers from England and France met at the designated point on December 1, 1990 at a depth of 40 m from the bottom of the strait. The error was only 358 mm horizontally and 58 mm vertically. By the way, British and French drillers made the last meters of the tunnel by hand - using picks and shovels.
The Eurotunnel was inaugurated by Queen Elizabeth II and François Mitterrand on May 6, 1994. One of the longest projects of mankind was implemented in just seven years. 13 thousand workers and engineers took part in its creation, about 10 billion pounds sterling was spent on the construction (taking into account inflation, almost twice as much as originally expected). The dream of Tomé de Gamon and hundreds of other guardians of the project has finally come true!
Longest tunnel
Today, the longest tunnel in the world is the Japanese Seikan railway tunnel, which connects the islands of Honshu and Hokkaido. Its length is 53.9 km. The Eurotunnel is inferior to it in total length, but its underwater section (about 39 km) is 15 km longer than the underwater section of the Japanese tunnel.
In 2015, the new leader promises to be the Gotthard Base Tunnel, which is currently under construction in Switzerland. The length of the tunnel will be 57 km.
The grandiose project of the twentieth century has not yet justified itself financially: only in April 2008 the company “ Eurotunnel»Announced its annual profit for the first time since its existence. It seems that the long-borne child has also proved to be a long-term payback ...
Illustrations for the article are provided by the company. Eurotunnel.
Bridge over the Channel
This is what the magazine "Science and Life" wrote about the next project of the bridge over the English Channel in No. 1 for 1890.
The present century, without exaggeration, can be called a century giant structures, one of which was the Eiffel Tower at the Paris Exhibition. Now a new, even more grandiose and important structure is being prepared - a bridge across the Channel, separating France from England. This bridge will be 28 kilometers long (almost the same number of miles).
The question of connecting England with France by a bridge or a tunnel has arisen for a long time. In 1873, the question of the Channel Tunnel was raised seriously. All the necessary research has been done; the feasibility of the enterprise has been fully proven; its profitability for both countries was beyond doubt; there were also capitalists who gave money for the implementation of the enterprise. The underwater tunnel project, however, failed for political reasons. Since the land forces of England are insignificant, there was a fear that a landing of troops might be made through the tunnel to England. Now a project has arisen to connect England with France not under water, but over water by means of a bridge of unheard-of size.
In England, a company was formed with huge capital " Channel bridge". Two famous English engineers took over the technical side of the matter: John Fowler ( Fowler) and Benjamin Becker ( Baker) and two famous French ones: Mr. Schneider and Mr. Gersan ( Hersent), managing one of the world's largest mechanical factories in Creusot. These four engineers have completed all the necessary studies and have already developed a detailed design for the bridge over the Channel.
The bridge is supposed to be built at the narrowest point of the strait, between Gris-Nez(from France) and Foxton (from England). The distance between these two points in a straight line is less than 28 kilometers; but the bridge will make a slight rounding to take advantage of the two existing shoals (banks Varna and Kolbarskaya). On these shallows, the sea is only 6-7 meters deep, which will significantly reduce the cost of building abutments-towers. The deepest sea in this direction is 55 meters (27 fathoms) at low tide.
Thus, it is necessary: 1) to build foundations (hereinafter we will call them towers due to their extraordinary size) at a great depth; 2) raise the bridge itself so that the largest sea vessels pass under it. According to the preliminary draft ( Arant-Projet), the builders think to achieve it this way.
The towers (abutments) of the bridge will be made of granite with steel fasteners. The size of these towers can be understood by the fact that the largest of them (at a depth of 55 meters) will have a base area of 1604 square meters. Only steel will be used everywhere because of its strength. The towers will require 76,000 tons of steel and 4 million cubic meters of granite. In addition, an additional 772,000 tons of steel will be required for the topside of the bridge. The total cost of construction is estimated at 860 million francs, but it could reach a billion.
The towers are built using iron caissons, from granite blocks, fastened with steel ties and cement. The masonry rises 21 meters above the water surface at low tide and 14 meters at high tide (the channel level fluctuates by 7 meters). Consequently, at a depth of 55 meters, the stonework will be 76 meters high, assuming that the stonework will begin right on the seabed.
The stone towers will each have two towers steel towers... The latter will be held together by huge steel beams and will be 40 meters high. The rails will lie another 11 meters higher, so that the trains will run at a height of 72 meters (about 35 1/2 fathoms) from the sea surface (at low tide). But the steel binding goes above the level of the rails by another 54 meters. Thus, the main tower, erected at a depth of 55 meters, will have a total height of 181 meters (90 fathoms), including 76 meters of masonry. Spans of the bridge on deep places will be alternately 500 and 300 meters; on smaller 350 and 200 meters, also alternately; finally, at the coast, the spans will alternate in 250-100 meters. Spans of 500 meters (half a mile) are more difficult Eiffel tower... But the technique is for last years has made such gigantic successes that the feasibility of this grandiose project is quite and undoubtedly possible.
The idea of connecting Great Britain with the continental part of Europe using a single engineering structure has visited the best minds on both sides of the strait for several centuries. Even calculations were carried out on the subject of what is preferable: a bridge or a tunnel. Napoleon Bonaparte intended to start construction, but some historical circumstances prevented this. The real tunnel under the Channel was only commissioned at the end of the twentieth century. Apart from preliminary preparation, the construction work itself took about seven years.
Tunnel under the Channel. Characteristic
There were many construction projects. The one that was eventually chosen turned out to be optimal both technically and economically. The length of the tunnel under the Channel is 51 kilometers, of which 39 are located directly under the strait itself. Railway tunnel, working in both directions at the same time. Provides the passage of both freight and passenger trains. A significant part of the cargo turnover is made up of passenger car traffic on open platforms. The Channel Tunnel allows you to get from London to Paris or back in a little over two hours. At the same time, it takes from twenty minutes to half an hour to overcome the tunnel itself. 
The movement is carried out in accordance with the English rules: in the left-hand mode. the entire distance of the track allows the train to develop a sufficiently high speed. The most amazing thing is that the grandiose tunnel under the Channel is not at all the largest in the world. He is inferior to the Japanese Seikan and the Swiss 
Some technical details
In fact, the Eurotunnel, as it is often called, consists of three parallel underground structures. In two, movement is carried out in opposite directions. And between them is a third, smaller diameter. Every 375 meters, it has exits to the main highways. The middle tunnel performs maintenance and repair functions. It also allows you to establish stable ventilation throughout the entire underground space and avoid the so-called piston effect - high air pressure in front of a moving locomotive. In addition, it is designed to ensure the safety of all transport communications. In case of occurrence emergency it should be used for evacuation of passengers. arose several times during the two decades of operation of the tunnel, but the system managed to prove its reliability during its operation. 
Eurotunnel opening
On May 6, 1994, a tunnel under the Channel was opened in a solemn atmosphere. Photos from the shores of the strait went around all the world news agencies, reports were broadcasted by all the world's leading TV channels. The Eurotunnel was torn off by Elizabeth and the President of France. Many official delegations from all over the world attended. The event caused a great public outcry.
The Thames, on which the English capital London stands, was a left tributary, on the banks of which the German was spread. When they melted, the sea level rose, and vast areas turned into the bottom and the English Channel. Britain became an island. However, the idea of re-linking the two most important parts of Europe by land has long been a cherished dream of the inhabitants of the Old World.
For two centuries, scientists have been developing different ways to overcome the English Channel. The tunnel project was first proposed more than 100 years ago, in 1802. Albert Mathieu proposed a project for crossing the English Channel, and the following year a similar plan arose on the other side, in England. True, then they were more inclined to build a bridge that would pass over the strait. This gigantic structure was supposed to consist of five-kilometer spans suspended over the sea on heavy-duty cables. The idea was rejected - such gigantic bridges had not yet been built, and experts began to doubt: will the construction be reliable? There were also quite unusual proposals. For example, about erecting artificial islands along the entire strait, and already from these islands stretch out bridges connecting with each other. But it was an even more surreal project. It was decided to stop at the construction of an underground road.
The idea of erecting a road leading from France to England had many opponents. Many people said that in the event of a war between the two countries, this tunnel can be used against the enemy. However, even then this objection was considered absurd. Indeed, when there is a threat of attack, it is very easy to quickly block the tunnel, blowing up or filling up even a small part of it. And the troops at the exit of the tunnel are more a convenient target than a formidable force.
For a long time, everything remained at the level of projects and plans. They seriously thought about building a tunnel only in 1955. They even started construction, started digging foundation pits. However, nothing came of this venture. Two years later, an energy crisis forced workers and engineers to leave the excavated pits, which were quickly filled with rainwater. Only 11 years later, the governments of England and France announced that they were ready to re-consider the possibility of a land connection of the two. But with one condition - all work must be carried out by private companies at their own expense.
The 9 best projects were selected, and for a whole year there was a serious debate about which one deserves more attention. A year later, in the opinion of the majority, the best was chosen. It was supposed to lay next to each other railways and highways for cars. However, the road under the strait had to be abandoned. First, a car accident in a tunnel is much more likely than a train wreck. But the consequences of such an accident in a long underground "pipe" can be serious and paralyze the movement for a long time. Secondly, an armada of cars rushing into the tunnel would inevitably fill it with exhaust gases, which means that a very powerful ventilation system would be required to constantly purify the air. And, thirdly, it is known that a trip in a tunnel tires the driver. We decided to focus on the design, which was described in the 1960 project and finalized in the mid-70s.
Work began on the English coast in December 1987 and on the French coast three months later. Huge machines with rotating cutting heads were laid a kilometer each month. All in all, it took three years to build the tunnel.
The tunnels were laid, on average, 45 meters below the seabed. When the two halves of the service tunnel were separated by only 100 meters, a small tunnel was manually dug to connect them. Until the moment of docking, 120 mine locomotives were taking out the rock from the faces, making a monthly path equal to two distances around the earth. The workers met at the end of 1990.
The completion of two railway tunnels took place on June 28, 1991. However, one should not think that the construction was completely completed at this point. Only the central tunnel was completed. And it was also necessary to dig a second, service tunnel, as well as lay the rails. More than 2,000 companies took part in the international competition for the right to receive an order for rails for the strait. French customers preferred products made in Russia.
The tunnel was completely opened relatively recently - on May 6, 1994. Queen Elizabeth II herself and President Mitterrand took part in its opening. After the official part, the Queen boarded a train and arrived from London's Waterloo station to the town of Calais on the French coast. In turn, Mitterrand arrived there from the Parisian Gare du Nord via Lille. When the locomotives of the two trains stopped nose to nose, the heads of the two states cut the blue, white and red ribbons to the sound of their countries' national anthems, which were performed by the orchestra of the French Republican Guard. Then the British and French delegations in Rolls-Royce vehicles crossed the tunnel to the British coast, to the town of Folkestone, where exactly the same ceremony took place as on the French side.
Features of the Channel Tunnel
In reality, there are three tunnels: two railway tunnels (one receives trains from France to England, the other from England to France) and one performs operational functions. Currently - this is the fastest way from London to Paris or (about 3). Passenger trains depart regularly from London's Waterloo and take you to Paris Gare du Nord or Brussels Midi-Zuid.
The diameter of each tunnel is 7.3 meters, the length is about 50 kilometers, of which 37 pass under the water column. All tunnels are clad in dense concrete frames, the walls of which are about 40 centimeters.
Special trains with platforms for cars and carriages for passengers leave every hour. In just a day, 350 electric locomotives pass through the tunnel, which makes it possible to transport more than 200,000 tons of cargo. Cars use tunnel trains like a moving highway. They enter the carriage at one end and leave at the other after a 35-minute ride. Electric locomotives reach speeds of up to 160 kilometers per hour.
There are many incidents associated with the Channel Tunnel. For example, on October 12, 2003, an unknown person was found there who had been living in a tunnel for ... 2 years, occasionally coming to the surface in order to stock up on food and water. It is strange that it was not discovered earlier, since a system of internal surveillance cameras is stretched along the entire length of the tunnel.
The following year, an emergency occurred in general: an employee of the English branch of Eurostar found 15 people on the railroad tracks. Some of them were injured, one very seriously. According to a British police spokesman, illegal immigrants (presumably Turks) were most likely found in the tunnel. Apparently, intending to get to England, they climbed into one of the freight train cars on the mainland, and then jumped off on the move in the place where the train slows down a little at the exit of the tunnel.
However, such violations are suppressed. For this there is a serious security service working 24 hours a day.
A total of £ 10 billion was spent on the entire project - twice as much as planned. A year after its official opening, Eurotunnel posted a loss of 925 million pounds - one of the largest negative sums in British corporate history. In addition, in 1996, truck traffic in the tunnel was suspended for 6 months due to a fire caused by a burning truck.
Despite the fact that the tunnel project proved to be very expensive and all the costs have not paid off so far, this structure still represents a piece of modern engineering excellence, taking into account safety and functionality in equal measure.
