On Sunday, in the Kerch Strait, more than 100 specialists - sailors, specialized engineers, employees of research institutes and bridge builders - began a complex maritime operation that could last about three days.
On the fairway supports The Crimean Bridge will be delivered and raised a railway arched span weighing more than 6 thousand tons.
Specialists emphasize that in preparing the operation, the experience of building other projects both in Russia and abroad was used.
“The marine operation in the Crimean Bridge project is, without exaggeration, unique for bridge construction: it is transportation, and then lifting and installation in the conditions of the sea with an unstable hydrometeorological background of an arched structure, the weight of which exceeds 6 thousand tons,” said the Deputy General Director for Infrastructure Projects of OOO “ Stroygazmontazh" Leonid Ryzhenkin.
Ten tugboats, boats and other vessels are involved in transporting the huge structure. According to experts, weather conditions were taken into account when preparing the most difficult operation. In the next 72 hours, the wind force, according to weather forecasts, should not exceed 10 m/s.
“On the eve of going to sea, the builders prepared the arch for loading onto floating supports. Two floating supports were set up under it, and, having received confirmation of a favorable weather forecast for the next three days, the builders loaded an arched span onto them. Early in the morning, the floating system began its five-kilometer journey from the Kerch coast to the bridge alignment, ”the Crimean Bridge information center said in a press release.
- RIA News
In addition, the movement of ships along the fairway in the strait has been suspended. It will be restored immediately after the builders confirm that the arched span is securely fixed at the design height. As Rosmorrechflot noted the day before, the restrictions on shipping in the Kerch Strait will not have a significant impact on the transit of ships.
The whole operation is divided into several parts. Upon completion of each of them, the quality of the work performed is strictly checked - their compliance technical documentation confirmed by the appropriate act of acceptance.
The structure will be raised to the design height at a speed of 5 m/h with the help of almost 700 cables, which will be combined into so-called strands of 40 cables in one. They will be attached to 16 jacks installed at the top of the fairway supports.
“By the time this operation is completed, the maximum allowable deviations of the structure along the bridge axis will not exceed 60 mm, and 30 mm across the bridge axis. Then the arch will be fastened with wind ties to the crossbars of the fairway supports, ”the press release of the Crimean Bridge information center says.
According to experts, the final installation of the installed railway arch on the fairway supports will be completed in a month. “Construction and installation work will be carried out from work sites installed on fairway supports and will not affect navigation in the Kerch-Yenikalsky Canal,” the press release emphasizes.
The second stage of the naval operation is scheduled for September - the installation of the road arch of the Crimean bridge, which consists of almost 200 large elements. Its assembly is already completed.
It should be noted that during the transportation and lifting of the navigable arches of the Crimean bridge on the fairway supports, unique floating systems are used, manufactured at the Sevastopol Marine Plant specifically for mounting these structures.
The fairway supports on which the arches will be installed are the largest supports of the Crimean bridge. Each of them consists of pile foundation and a monolithic slab on which racks with crossbars are installed. At the base of the supports there are 95 tubular piles sunk to a depth of more than 60 m.
The length of the navigable span of the Crimean bridge is 227 m. The height of the supports is 35 m. The preparation of the railway arch for installation has been going on since the beginning of August. The span was removed from the slipway, where it was assembled during the year. Then the builders moved the structure weighing more than 6 thousand tons to a distance of almost 90 m. At the same time, elements of traction and pushing devices were involved. The arch consists of more than 400 large elements, almost 4 km of butt joints of the first category were made, more than 600 thousand bolts with a total weight of 380 tons were screwed. The movement of trains along the Crimean bridge, the total length of which will be 19 km, is provided for on two tracks.
Proof of this is the current operation to install a road arch span, which has no equal in the world - a multi-ton metal structure 227 meters long is brought in from the sea to be installed on fairway supports to a height of 35 meters. You can’t call it otherwise than a miracle of technology. The idea to build a crossing across the Kerch Strait has existed since time immemorial, probably even when, in 1783, Prince Potemkin annexed the Crimea to Russia. But communication with the peninsula in this direction for a long time was only by ferry and shipping. Military sappers erected a ferry crossing here at the end of the Great Patriotic War, after the liberation of the Crimea from the Nazi troops.
But in 1945, the pontoon bridge was destroyed by the movement of ice, which moved from the Sea of Azov. The design itself, intended for river crossings of short length, was not adapted to sea conditions. It was decided to completely dismantle the building and design the construction of a new, more reliable structure.
However, neither in 1949, nor in 1991, the developed and even approved projects for the construction of a bridge in the Kerch Bay did not receive their real implementation. The complexity of the technical execution of projects (and there were several of them) and the lack of such large-scale funding also affected. They were satisfied with land communication, road and rail, through the territory of the then Ukrainian SSR, present-day Ukraine - then there were no problems on its part.
They returned to the topic of building a bridge in the Kerch Strait in 2003, when Ukraine was already fully slurping its “independence” and considered Crimea its “original” territory. Because of the intention on the part of Russia to build an artificial dam to the island of Tuzla, a serious conflict arose with official Kyiv. More than ten long years remained before the return of Crimea, and the scandalous situation hushed up on its own. But even then it became clear that the historical identity of the peninsula would be restored sooner or later. What, in fact, happened as a result of the popular referendum in 2014. And after just some three years, Crimea had the opportunity to receive reliable communication with the mainland.
“It took quite a long time to figure out how to build a bridge across the Kerch Strait,” says the expert, in the recent past official representative Railway Troops of Russia Alexander Komarov. - Several projects were envisaged, where the length mattered, because a kilometer of the highway on the ground and over the sea area have significant differences, including in terms of cost. The main construction options included the following projects. "Northern" - from Cape Lantern to Small Kut. The length of the structure would be at least 10 kilometers, while the railway line would have to be pulled 24 kilometers, and the automobile line twice as much. The Zhukovsky route could connect Zhukovka and the Chushka Spit - there are only 6 kilometers, but the access roads of all types of transport are very long. The Yenikalsky project was supposed to stretch from Cape Yenikalino to the Chushka Spit, but even here, with a relatively short distance, everything rested on long-distance access roads. The "Tuzla" direction was seen from Cape Ak-Burun to the island itself - also a very long way. But it was he who became decisive in choosing the site for the construction of the bridge. There are a number of circumstances that made it possible to choose this direction. The new bridge here will not interfere with the already existing ferry service through the ports of Kavkaz and Krym. Again, there are opportunities for further development, including through space for accommodation building materials. There are opportunities to further ensure the operation of the new bridge. Figuratively speaking, linemen also need to be based somewhere, and preferably in the immediate vicinity of the road.
It is already clear how the Crimean bridge across the Kerch Strait is being built, and the installation of the arched car arch is almost live, and this can be seen on TV news, including on the Zvezda TV channel. Let's briefly look, or rather recall, some of the characteristics of this unique design. The total length of the bridge across the Kerch Strait will be 19 kilometers. Its construction began simultaneously with 8 points. The length of the offshore sections from the Tuzla Spit to Tuzla Island (there is 6.5 kilometers of land) and from the island to Kerch will be 13 kilometers. For the construction of the bridge, about 600 supports and more than 5.5 thousand piles of various sizes are used.
“It is impossible for a non-professional to visually assess the scale of such construction, the picture in television programs cannot convey the complexity of the tasks performed by bridge builders,” Alexander Komarov continues. - This is not just a huge amount of work, but also the genius of the technical thought of our engineers, the uniqueness of the equipment, including six-hundred-ton jacks, which are now involved in the installation of the arch of the automobile span. It is no coincidence that the Crimean bridge is now called the "eighth wonder of the world" and there is no exaggeration here. But if the construction of the Tower of Babel, a failed miracle of architectural thought, led to a misunderstanding of people speaking different languages, which prevented the construction of the "tower to heaven", then the bridge across the Kerch Strait, on the contrary, becomes a symbol of unity and friendliness between people.
The Crimean bridge across the Kerch Strait promises to be the largest in Europe. Now the longest bridges in Russia are located in St. Petersburg - the Southern Flyover of the Western High-Speed Diameter, which is a two-story bridge across the Sea Canal and a cable-stayed bridge across the Ship Fairway (9378 meters), as well as the Northern Flyover (8794 meters).
In the world practice of building bridges, the championship is held by China, where the Danyang-Kunshan viaduct, a railway bridge, which is part of the Beijing-Shanghai high-speed railway, is located, with a length of 164 kilometers. The Qingdao Bridge across the Jiaozhou Bay was also built there, the length of which is 42.5 kilometers. There are long bridges in the USA, Egypt, Japan.
With its more “modest” 19 kilometers, the Crimean bridge impresses not with its length, but with the uniqueness of technical technologies, in which one of the main ones is the construction of arched spans at high altitude. After all, the Kerch Strait connects the Black Sea with the Sea of Azov and there is active shipping, including large-capacity dry cargo ships and cruise liners, which will easily fit under the new bridge. And he, indeed, has no analogues in the world.
The operation was controlled by engineers, scientists and a mobile weather station.
The construction of the Crimean bridge across the Kerch Strait has finally reached its peak. The railway arch weighing more than 6,000 tons was raised to the design height - 35 meters above sea level. The length of the multi-ton structure is 227 meters. There have been no operations of this scale in the Russian bridge building yet.
frame from video
The arch, installed on two pontoon ships, set sail yesterday. A cavalcade of ships with an arch in the middle covered a distance of 4 km in a few hours. At the same time, for the passage of the caravan, it was necessary to carry out preliminary dredging. In fact, a new fairway was dug to move the arch.
The structure was raised to the design height for 12 hours. From an engineering point of view, the process is quite complex and time-consuming, more than 30 slingers, surveyors and quality specialists took part in it. They began to raise the arch at midnight, and finished only in the morning. The rise was carried out with the help of 16 crane installations, and the arch itself was held on 700 cables.
The construction work was broadcast live, so anyone could see this historical moment with their own eyes. When the pontoon barges carefully brought the arch into the alignment between the supports, the most important thing began - the rise, which took place almost a centimeter. To begin with, the arch was raised a meter and left in limbo for an hour. Crane jacks were loaded gradually - starting with a bar of 5 tons, and ending with a maximum load level of 100 tons. The process was observed not only by Internet users and third-party viewers who settled on the shore, but also by scientists. Special sensors were installed on the arched span, thanks to which it was possible to track any changes, including deformation and deflection of the structure. Scientists monitored the lifting and installation throughout the entire time to ensure the correct progress of work and prevent emergencies.
For Russian engineers, the rise has become a kind of know-how, since they had no such experience before. Despite this, the rise and installation took place in the normal mode. As the builders admitted, the first 10 meters were the most difficult - then the process went faster.
- The sea operation in the Crimean Bridge project is, without exaggeration, unique for bridge building: it is transportation, and then lifting and installation in sea waters with an unstable hydrometeorological background. Such an operation would not have been possible without the gigantic experience gained by the bridgemen in other projects,” said the Deputy CEO construction organization Leonid Ryzhenkin.
To avoid emergency situations, weather stations were installed on the boats, which regularly monitored weather changes.
“The mobile weather station continuously records the direction and speed of the wind, pressure, humidity levels and visibility,” said Sima Ayvazyan, head of the Crimean Bridge information center.
The arch provides not only railway tracks in both directions. The structure includes inspection passages, lots for cable routes, drainage drains, lightning protection and grounding, strength control systems, air and ship navigation, as well as signaling, mechanized interlocking and blocking functions, communication points and lighting poles. The arch has architectural lighting, so the most fascinating view of it will open at night. According to the Crimean Bridge portal, up to 47 pairs of trains will be able to pass through the bridge per day. Passenger trains will be able to reach speeds of up to 120 kilometers per hour, and freight trains - up to 80.
At the time of the rise of the arch, the passage through the Kerch-Yenikalsky Canal for ships was suspended. The temporary stoppage of navigation did not bring any problems. On Monday morning, only 28 ships were anchored in the port of Kerch, which is almost half the usual number. For example, in bad weather, more than 60 ships anchor.
During September, the builders will finish mounting the end elements of the arch, as well as lower it onto special supports. The next step is to lift and install the car arch, which weighs about five thousand tons. Its installation is also scheduled for September. The road arch has already been assembled and is waiting in the wings on the shore from Kerch. Recall that the Crimean bridge will be the longest in Russia - 19 kilometers, so its construction is not in vain called the "construction of the century." The start of road traffic is scheduled for December 2018, and the first trains from the mainland of the country to the peninsula will depart a year later, on December 1, 2019. The cost of the facility amounted to more than 200 billion rubles.
The crossing across the strait is already striking in its dimensions. This is especially true for arched automobile and railway structures. In order to install one or another arch of the Crimean bridge, the dimensions of which are very large, special mechanisms were used - crossings, cranes, sea vessels.
The dimensions of the arches of the Crimean bridge are the same, they differ in weight and width. Otherwise, the designs are identical, which is fully consistent with the project documentation.
Dimensions of the arch of the Kerch bridge: features
The crossing across the strait consists of railway and automobile spans, which will allow two types of transport to be put on the bridge. The width of the automobile arch of the Kerch bridge is 10 meters greater than that of the railway one, but it has less weight. Among the technical parameters of both designs, it is worth noting such as:
- The weight of the automobile arch of the Kerch bridge is 5.5 thousand tons, and the weight of the railway arch is 5.8 thousand tons;
- The length of the arch of the Kerch bridge is 227 meters;
- The height of the arch of the Kerch bridge from the water at the highest point is 45 m;
- The railway arch is assembled from hundreds of elements - pendants, arched vaults, blocks, braces;
- The span of the railway bridge is made as a combination of a span structure with through trusses and arches. The trains will move along the trusses, which are connected to the arch by pendants;
- The width of the arch of the Kerch bridge along the axes is 20 meters (in tightening), and five meters at the highest point;
- The railway arch has special drainage systems, systems for cables, ship signaling, engineering communications monitoring, air navigation, as well as lightning protection and grounding. Additionally installed architectural lighting, blocking system, lighting. Because of this, the weight of the railway arch of the Kerch bridge is greater than that of the automobile one;
- Movement along the car arch will be carried out on a rigid tightening from below.
How much does the arch of the Crimean bridge weigh: materials
In order to raise one and the second arch to the desired height, a special technique was used. The weight of the arch of the Kerch bridge required a phased installation of structures on floating supports, and then a gradual lifting with jacks.
Of no small importance to the weight of these parts of the bridge was the width, the materials used to make the span, the length of the arch of the Crimean bridge. The spans were assembled from metal structures, which were manufactured at the factories of Belarus and Russia. The final assembly took place already on the observation deck.
The height of the arch of the Kerch bridge in the bridge part reaches 35 m. Such dimensions of the gigantic structure required the use of a special system of ropes made of metal wire.
Given that the weight of the arch of the Crimean bridge is very large, it was necessary to build special floating supports, on board of which there were diesel-hydraulic stations. She supplied electricity to the ballast pumps to fill the ballast compartments.
The greatest difficulty was caused by the raising of the railway arch. Such a weight of the railway arch of the Crimean bridge required the use special courts, boats, equipment and attracting a large number of specialists in various fields.
The builders raised one of the two largest structures of the bridge across the Kerch Strait to the fairway supports, to a height of 35 meters above sea level. This is a railway arch span weighing 6 thousand tons. The whole process took about 12 hours, during which time navigation along the Kerch-Yenikalsky Canal was limited.
A video appeared on the Internet showing how bridge builders raised the arched railway span of the Crimean bridge to the fairway supports - to a height of 35 meters from sea level. Reports about it information centre project "Crimean bridge".
The process of lifting the arch weighing more than 6 thousand tons to the design height took about 12 hours. During the day, the structure will be fixed.
“The ascent went smoothly. Up to the mark of 10 meters we went more slowly, did a lot of control tests, carried out geodetic control over the state of the structure. Then the main climb began. The arch was raised slightly above the design height for subsequent lowering onto the supporting parts. During the coming day, the structure will be equipped with wind ties - these are devices that fix the arch, ”said Mikhail Piksaev, deputy director for the production of Mostootryad-1.
For the installation of the overall structure, “strands” of high-strength cables were fixed along both edges of the arch span, stretched to the arch from 16 jacks installed at the top of the fairway supports. The arch was raised on 700 cables with powerful jacks fixed on supports. The carrying capacity of each jack is 650 tons, so, despite the weight of the arch of 6,000 tons, the builders provided a 40 percent margin for lifting mechanisms,” the Crimean Bridge Information Center said. Jacks were loaded gradually. The initial load of 5 tons was increased to 100 tons. The structure was raised without deviations, within the alignment between the two supports.
After the "detachment" of the arch from the floating system by one meter, it was kept suspended for an hour. During this time, the specialists once again checked the reliability of all mechanisms and only after that continued the ascent.
The floating supports, with the help of which the arch was towed, returned to the Kerch coast. They will be rechecked and re-equipped, after which the second arched arch will be transported and installed in the same sequence. superstructure- road. As a result, two arched spans will rise above the fairway, under which ships will pass unhindered. In the next month, the builders will mount the end elements of the arch, as well as unroll it - lower it onto special supporting parts.
Installing the arches of the Crimean bridge in the design position is a unique technological operation.
For the first time in the history of domestic bridge building, transportation, positioning in sea conditions and installation from the water on supports of an overall navigable span are carried out.
The maritime operation is carried out in conditions of limited navigation with a time "window" of 72 hours. In general, the operation brought together hundreds of specialists - these are sailors, specialized engineers, employees of research institutes and ordinary bridge builders.
For the duration of the operation, navigation along the Kerch-Yenikal Canal was limited. The ban did not apply to ships and ships of the Navy, as well as federal bodies security. Vessel traffic will resume as normal. The final installation of the arch on the fairway supports will take another month.
The arched span of the railway part of the Crimean Bridge is a combination of a span structure with through main trusses and an arch. The movement of trains goes along the elements of the farm, while the arch in the conditions of such an extended span performs a supporting function. Farm elements and arches are connected by pendants. Span length - 227 m. Height at the highest point - 45 m. Width along the axes of the arches - 20 m in tightening, 5 m in the castle (upper point). Trains run on two tracks. The design provides for inspection passages, cable support systems, drainage trays, lightning protection and grounding, a monitoring system for engineering structures, aeronautical and ship alarms, a centralization and blocking system (SCB), communications and lighting poles, and architectural lighting.
The total cost of the Kerch Bridge will amount to 227.92 billion rubles in the prices of the corresponding years. The bridge will be the longest in Russia, it will connect the Crimean peninsula with the mainland of the Russian Federation by road and rail.
The capacity of the four-lane highway will be 40,000 vehicles per day, Railway will include two tracks with a capacity of 47 pairs of trains per day. The movement of cars on the bridge should open in December 2018, trains - on December 1, 2019. Every day, more than 200 basic pieces of equipment, more than 20 pieces of watercraft and more than 5 thousand people are involved at the facility.
Kerch Bridge is one of the largest bridges in Russia. Its length is 19 km. The route starts on the Taman Peninsula, passes along the existing five-kilometer dam and Tuzla Island. Then it crosses the Kerch Strait, skirting Cape Ak-Burun from the north, and comes to the Crimean coast.
Earlier, Kyiv expressed dissatisfaction with the construction of a bridge across the Kerch Strait by Russia, because, according to the head of the Ministry of Infrastructure of Ukraine Yuriy Lavrenyuk, this will lead to a reduction in the number of ship calls to the ports of Mariupol and Berdyansk. This circumstance, in turn, will lead to a decrease in the profits of trade operators and the administration of Ukrainian seaports.