Tunnel under the English Channel. Channel Tunnel Eurotunnel Channel Tunnel

Money changes the world, sometimes literally. Today, people can build and move large objects at incredible speeds. We can dig through mountains, redirect rivers, create new islands and many other things that seemed impossible just a few decades ago. Judging by the current pace, humanity is not going to stop there in the near future. Absolutely every project has a final cost, most often calculated in US dollars. What does it take to pave roads, pour streams of concrete, lay communication cables and motivate workers? This is money. Hundreds of billions of dollars are spent on construction every year, and as the world gets bigger, more structures must be built. I present to your attention a list of the ten most expensive construction projects that have ever been created in the history of mankind. Construction costs were adjusted for inflation to reflect what they would cost today.

Channel Tunnel – $22.4 billion

Also called the Eurotunnel, the Channel Tunnel stretches underwater between the southern coast of England and the northern coast of France. The construction cost fifteen French and British companies $22.4 billion. Increasing safety requirements and environmental measures led to an increase in the final cost of the project by 80% of the original budget. Tunnel boring machines began excavating projects in 1988, and the tunnel began operating in 1994. Ten workers tragically died during the construction work. The Channel Tunnel consists of three parts: two railway tunnels 25 feet in diameter and one service tunnel 16 feet in diameter. Each span is 31 miles long. There were many fires in the Channel Tunnel. Few of these incidents caused damage that did not require prolonged closure of the tunnel. Security services have repeatedly stopped attempts by illegal immigrants to enter England illegally. The most common way is to try to travel in the trunk of a car, or on a Eurostar train.

Channel Tunnel, FRANCE

The Channel Tunnel is also called the Euro Tunnel. The Channel Rail service runs between Cheriton near Folkestone, Kent, and Coquelles, near Calais. The tunnel is one of the greatest civil engineering projects of the 20th century. It has a design capacity of 600 trains per day in each direction.

The length of the Channel Tunnel is 50 km, of which 39 km is underwater, which includes two railway tunnels and one service tunnel. The two railway tunnels have a diameter of 7.6 m, the central tunnel has a diameter of 4.8 m, which is used for maintenance and ventilation, and, if necessary, the evacuation of passengers in case of emergency. There are also several track switches that switch trains from one rail to another as needed.

The depth of the tunnels is 45 m below sea level. The total number of railway tracks is 195 kilometers, of which 45 kilometers pass through the territory of Great Britain, and 50 km are laid through the territory of France. Traveling from one end to the other takes about 30 minutes.

History of the Channel Tunnel

The Channel Tunnel is one of the largest privately funded engineering projects in history.
French mining engineer Albert Mathieu envisioned building the Channel Tunnel as early as 1802. Many other schemes and projects have appeared over the years. In 1875, the Channel Tunnel, conceived by British engineer John Hawkshaw, was given the green light to build the tunnel by the British and French governments. And in 1881, a new Act gave his rival William the right to implement his own project.

In 1882, the British Parliament banned the use of the tunnel, mainly on national security grounds. And in 1922, the Construction Law allowing it was again adopted, but was soon banned again. In 1960, an alliance of British and French companies began to build the Channel Tunnel. Work stopped in January 1975 after the 740-meter long tunnel was completed. In the 1980s, construction companies began work again, but the project was soon abandoned. In November 1984, the Governments of two countries, France and Great Britain, decided to support the resumption of construction. Construction resumed in April 1985.
In October 1987, the company's shares began to be listed on the stock market.

The tunnel, which cost nearly $16 billion in US dollars, has more than doubled its original cost. The Channel Tunnel was officially opened by Elisabeth II of Great Britain and French President François Mitterrand during a ceremony on May 6, 1994. Almost 7 million passengers are transported through the tunnel every year. In its first six years of operation, the tunnel saw 112 million passengers use its service.

This is not a simple story of the Channel Tunnel. But still, it was built, if you are in the UK or France, don’t forget to admire it and take a ride in the tunnel.

1. The length of the Channel Tunnel is 51 km, of which 39 pass directly under the strait. Trains traveling from London to Paris and back spend 20 to 35 minutes in the tunnel.

2. Thanks to the Eurotunnel, you can travel from Paris to London by train in just 2 hours and 15 minutes.

3. Contrary to misconception, the English Channel Tunnel is not the longest railway tunnel in the world, but only ranks third.

The second place is at the Japanese Seikan tunnel, connecting the islands of Honshu and Hokkaido, the length of which is 53.85 km.

And the longest in the world is the Gotthard railway tunnel in the Swiss Alps, the official opening of which is scheduled for 2017. Its length is 57 km.

4. The idea of ​​building a tunnel connecting England and continental Europe was first mooted at the beginning of the 19th century, but was rejected for a long time due to British fears that the structure could be used for a military invasion of the island.

5. Construction of the tunnel began in 1881 and 1922. For the first time, the builders managed to cover 2026 meters on the English side and 1829 meters on the French side. In the second, tunnel drilling stopped at only 128 meters. Both times construction was interrupted for political reasons.

6. In the post-war period, the Channel Tunnel project progressed extremely slowly.

The research team began work in 1957, the project was approved in 1973, after which it was frozen again, and the actual construction of the tunnel began only on December 15, 1987.

7. The Eurotunnel technically consists of three tunnels - two main ones, which have 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 of maintenance personnel and emergency evacuation of people in case of danger.

8. Road transport travels through the Channel Tunnel in special trains.

At the same time, drivers and passengers of passenger cars transported by Eurotunnel Shuttle trains do not leave their vehicles. The procedure for loading a car into a carriage takes no more than eight minutes.

9. Over the twenty years of operation of the Eurotunnel, seven major incidents occurred in it, due to which the normal operation of the tunnel was disrupted for a period of from several hours to several months.

Most of the incidents were related to fires, however, thanks to the professional actions of rescuers, casualties were avoided.

10. A total of about £10 billion was spent on the construction of the Eurotunnel, and the project cost of construction was exceeded by 80 percent.

According to experts, the payback period of the project may exceed 1000 years.

The Thames, on which the English capital London stands, was a left tributary, on the banks of which lies the German River. When they melted, sea levels rose, and vast areas became the bottom of the English Channel. Britain became an island. However, the idea of ​​​​reconnecting the two most important parts of Europe by land has long been the 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 next year a similar plan arose on the other side, in England. True, at that time 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 above the sea on heavy-duty cables. The idea was rejected - such gigantic bridges had never been built before, and experts doubted: would the structure be reliable? There were also completely unusual proposals. For example, about erecting artificial islands throughout the entire strait, and from these islands stretching bridges that connect with each other. But this was an even more unrealistic project. It was decided to stop at building an underground road.

The idea of ​​building a road leading from France to England had many opponents. Many people said that in the event of a war between two countries, this tunnel could be used against the enemy. However, even then this objection was considered absurd. After all, if there is a threat of attack, it is very easy to quickly block the tunnel by blowing up or filling up even a small part of it. And the troops at the exit of the tunnel are more of a convenient target than a formidable force.

For a long time everything remained at the level of projects and plans. They started thinking seriously about building a tunnel only in 1955. They even started construction and started digging pits. However, nothing came of this venture. Two years later, the energy crisis forced workers and engineers to abandon the dug pits, which quickly filled with rainwater. Only 11 years later, the governments of England and France announced that they were ready to again consider the possibility of a land connection between the two. But with one condition - all work must be carried out by private companies at their own expense.

9 of the best projects were selected, and for a whole year there was serious debate about which one deserved more attention. A year later, according to the majority, the best was chosen. It was supposed to lay railway tracks and highways for cars next to each other. However, the road under the strait had to be abandoned. First, a car accident in a tunnel is much more likely than a train crash. But the consequences of such an accident in a long underground “pipe” can be serious and paralyze traffic for a long time. Secondly, an armada of cars rushing into the tunnel would inevitably fill it with exhaust fumes, which means a very powerful ventilation system would be required to constantly clean the air. Well, thirdly, it is known that traveling in a tunnel tires the driver. We decided to go with 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 laid a kilometer a month. In total, the construction of the tunnel took three years.

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 dug by hand to connect them. Until the moment of docking, 120 mine locomotives removed rock from the faces, monthly traveling a distance equal to two distances around the earth. The workers met at the end of 1990.

The completion of the two railway tunnels took place on June 28, 1991. However, do not think that the construction was completely completed. Only the central tunnel was completed. And it was still necessary to dig a second, service tunnel, and also lay 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 those 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 ceremonial part, the Queen took the train and arrived from London Waterloo station to the town of Calais on the French coast. In turn, Mitterrand arrived there from the Gare do Nord station in Paris via Lille. As the locomotives of the two trains stopped nose to nose, the two heads of state cut the blue, white and red ribbons to the sounds of their countries' national anthems, which were performed by the band of the French Republican Guard. Then the British and French delegations in Rolls-Royce cars 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 route from London to Paris or (about 3). Passenger trains depart regularly from London Waterloo and take you to Paris's 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 depart every hour. In total, 350 electric locomotives pass through the tunnel per day, which makes it possible to transport more than 200,000 tons of cargo. Cars use the tunnel trains as a moving highway. They enter the carriage at one end and exit at the other after a 35-minute journey. 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 discovered there who lived in a tunnel for ... 2 years, occasionally coming to the surface 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: an employee of the English branch of Eurostar discovered 15 people on the railway tracks. Some of them were wounded, 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 carriages of the freight train while still on the mainland, and then jumped off while moving in the place where the train slows down a little at the exit of the tunnel.

However, such violations are suppressed. For this purpose, there is a serious security service working 24 hours a day.

The entire project cost £10 billion - twice as much as planned. A year after its official opening, Eurotunnel announced losses of £925 million - one of the biggest negative amounts in British corporate history. Additionally, in 1996, freight traffic through the tunnel was suspended for 6 months due to a fire caused by a truck that caught fire.

Although the tunnel project was very expensive and the costs have not yet been recouped, the structure still represents an example of modern engineering excellence, taking safety and functionality into account in equal measure.

After many centuries of mistrust, which at times led to military conflicts, the French and English were finally united... by a common dislike of seasickness. The waters that have separated Britain from France for the past 8,000 years have been very capricious and have often made ferry crossings an ordeal for passengers.

However, the unshakable belief of the British Empire in the need to preserve this semblance of a giant fortress moat until recently forced travelers to choose the air route or swim, painfully hanging overboard. Britain's accession to the European Union marked the beginning of a new relationship between old rival neighbors. In an effort to overcome all obstacles on the path to unity, the countries began to develop a project that would forever link their shores. Various proposals were received: 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 information received from geologists. They found that underwater the two countries were already connected by a layer of chalk-marl rock. This soft limestone rock was ideal for tunnel construction: it is quite easy to mine, has high natural stability and water resistance. Many wells drilled at the bottom of the English Channel and advanced acoustic sounding technology have given geologists the opportunity to obtain fairly accurate data about the underwater relief of the strait and the geological structure of its bottom. Using this information, engineers decided on the tunnel route.

To better control traffic flow, as well as avoid the huge ventilation problems that would inevitably arise in a 39-kilometer road tunnel, engineers opted for a rail tunnel. Now, instead of a ferry, cars and trucks board special freight trains that transport 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 will be spent in the tunnel. Another train called the Eurostar transports passengers from central London to the center of either Paris or Brussels in just over three hours.

One of the greatest structures of the 20th century, the Channel Tunnel, is actually a complex system consisting of three “galleries” that run parallel to each other. Trains travel from England to France through the northern tunnel, and back through the southern tunnel. Between them there is a narrow technical tunnel, the main function of which is to provide access to the working tunnels for routine repairs. It is also intended for the evacuation of passengers. Increased 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 interconnected 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 connected to each other every 244 meters by airlocks. Thanks to the locks, the air pressure that arises under the pressure of the moving train is neutralized: the air in front of the train, without causing any harm to the train, flows 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 shield. By punching a tunnel, the TPK leaves behind an almost completed structure - a cylindrical tunnel lined with concrete. In front of each TPK there is a working installation. It consists of a rotating rotor that literally “cuts” the rock.

The rotor is forcefully pressed against the face surface by a ring of hydraulic cylinders, which also direct its movement. Directly behind the drill head there are hydraulic spacer cylinders. They press giant spacer plates against the walls, against which they push the cylinders and rotor away. Behind the working unit there is a control panel, from where the TPK operator monitors the progress of the drill head. Thanks to the laser navigation system, the complex absolutely 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 attachments with steel discs, or a combination thereof. Rotating, the rotor cuts out concentric circles in the lime-chalk rock. At a certain depth, the cut rock cracks and splits. The broken pieces fall onto the conveyor, which transfers the waste rock to the trolleys already waiting for it at the tail of the tunneling complex

The last element of the TPK that needs to be mentioned is the mechanical lining stacker.

He installs lining segments on the tunnel walls. Behind the working TPK there is a technical staff 240 meters away. 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 in the hope of meeting safely under the water in the middle of the strait. The remaining five worked on land, designing the entrance areas of the future tunnel. The builders first planned to break through a technical tunnel - it was supposed to become a kind of “advanced landing force” in the overall system.

However, even with an arsenal of ultra-modern technical means, when breaking through the Eurotunnel, not everything went according to plan. Let's start with the fact that English TPKs were designed to work only in “dry” faces. Needless to say, when somewhere in the middle of the excavation the face began to flood with salt water entering through cracks in the rock, the builders had a very difficult time. The TPK on the British side of the working tunnel had to be stopped. Engineers urgently decided 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 cement slurry into the resulting cracks. The tunnel ceiling above the TPC was then dismantled and covered with steel panels and a thin layer of shotcrete was applied to them. Only after this did work on the English side continue.

All three tunnels are covered with a circular concrete lining consisting of individual segments. The segment that “closes” each ring is smaller in size than the others and has a wedge shape. This form subtly reminds us that this modern design 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 just over 90 meters, the TPK was stopped. To make sure that both halves of the tunnel were in line, a probe hole with a diameter of 5 centimeters was drilled on the English side. When she reached the “French” part of the tunnel, a narrow connecting corridor was cut between them by hand. It was then expanded to the required diameter using small mining machines. Six months later, the main tunnels were connected. The work ended in a very interesting operation from a technical point of view. Instead of spending effort and money on dismantling and extracting their drill heads to the surface, English engineers simply directed them down, and the mechanisms themselves dug their final refuge. When the drilling equipment disappeared into the ground and the resulting depressions were filled with concrete, French TPKs passed above them into the English part of the tunnels.

When constructing any tunnel - especially if we are talking about a giant 50 kilometers long - one must carefully plan how the waste soil will be extracted and disposed of. The far-sighted British built a huge dam for these purposes, enclosing several sea lagoons not far from the entrance shafts of the tunnel. The spent soil was lifted up and poured into these lakes. Once dried, they increased the territory of Great Britain 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 shore. When the lake dried up, the resulting plot of land was sown with grass. The area of ​​the country, alas, remained the same, but one green corner became larger.

To ensure uninterrupted train movement 24 hours a day, even if part of the route had to be temporarily closed, two intersecting crossings were built in the main tunnels, they are also called passing chambers. They are located approximately a third of the way from each bank. Thanks to them, the train can always bypass the blocked section through 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 for the most extreme cases, the Channel Tunnel will work!

The patrol cells were built very large - about 150 meters long, 20 meters wide and 15 meters high each. To strengthen their structure, the rock around the siding chambers was reinforced with shotcrete and 4-6-meter steel rods - anchor bolts.

During the construction of the chambers, workers installed measuring instruments in the chalk rock to monitor the condition of the soil. If a problem was discovered, the thickness of the skin or the length of the anchor bolts was 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 waste soil was removed.

Massive shutters were installed in the completed traveling cameras. They must prevent the spread of fire in the event of a fire; they are also used to independently supply air to each of the tunnels. The gates open only when the siding needs to be used.

After all the tunnels were completely punched, work continued for another two years. Workers installed miles of cables for security systems, signaling, lighting and pumping equipment. Two pipes were installed through which cooled water was constantly supplied to reduce the air temperature in the tunnel, which increased due to the movement of high-speed trains. All equipment, including the trains themselves, has been tested many times.

By the end of 1993, construction of the Eurotunnel was completed. And in May of the following year, this most expensive engineering facility in the history of mankind began to operate.

David McAuley. How it was built: from bridges to skyscrapers.