Transverse sliding is a technology for the construction of spans over the water area used in the construction of the Crimean bridge. Such an operation is carried out on a site in the so-called channel - between the Tuzla Spit and the island of Tuzla.
The spans are installed on marine supports from the working bridge No. 1. First, the span weighing more than 200 tons is assembled from factory blocks at the stand. Further, on multi-wheeled self-propelled modules, the structure is moved to a working bridge, where special roll-out tracks are equipped.
According to them, the structure is moved to the supporting parts and set in the design position. Transverse sliding is used in this section, since all spans between the spit and Tuzla Island are mounted at the same level - 4 meters. In the sections from Tuzla Island to the fairway, where the bridge begins to rise to 35 meters, the longitudinal sliding method is used.
The arched spans of the Crimean Bridge are assembled at a technological site on the Kerch coast - a road span weighing more than 4,000 tons and a railway span weighing almost 6,000 tons.
Completed structures will be moved one by one to be installed on fairway supports. The railway arch will be transported first, then the road arch. The arched spans will rise 35 meters above the sea and ensure unhindered passage of ships under the bridge.
Offshore operations to install the arches in the design position are scheduled for August - September this year. The path from the Kerch site to the fairway is just over 5 km. A weather window with a favorable forecast for 72 hours will be required to carry out the paramount marine operation. The transportation of the arch itself will take several hours and will be carried out during daylight hours. Taking into account the technological operations for lifting and fixing the arch to the supports, the marine operation will take about a week. The transit of ships through the Kerch-Yenikalsky Canal in the bridge construction area will be temporarily stopped, about which the shipowners will be informed in advance.
About 70% of all pillars of the road bridge across the Kerch Strait is ready; by September, the builders plan to start laying asphalt concrete on the completed bridge spans. To date, 264 bridge supports out of 595 provided for by the project (44% of the project) are ready, in total 202 of which are automobile supports (about 70% of all road bridge supports). Today, on all land sections of the road bridge, the pipe piles are all loaded. The plans for the near future include the continuation of immersion of pipe piles in the water area. Today there is work going on on a broad front. Work is underway on about 160 more pillars, as well as the assembly of superstructures and the concreting of a monolithic slab of the roadway.
In early May, the builders plan to work out the technology for laying asphalt concrete on land sections, and by August-September they will start laying asphalt concrete on the already finished superstructures of the road bridge. At the moment, more than 5,800 tons of metal structures of arch spans have been assembled out of almost 10,000 tons. By August, when the fairway supports are ready, the navigable arches on the floating system will be raised to the ready supports. Builders do not slow down and by rail. It is planned that about 30% of the supports railway will be ready this year, and bridge builders will also assemble span structures by rail. As for the road, about 14 kilometers of the roadway will be ready by the end of the year.
A new stage in the construction of the Crimean bridge in the Kerch Strait - workers began to build spans between the sea pillars. In total, specialists will have to build six kilometers of canvas over the water surface. And this is a real art - to carry out work of such complexity.
Slowly but surely. The canvas of the Crimean bridge is moving forward - it is already above the sea. The speed of movement is 20 centimeters per hour. In order for this process to be visible to the naked eye, the speed of the video frames had to be increased several times. However, the pace is decent for structures of this magnitude.
“In total, there are four offshore sections at the construction site, including the section above the fairway. Their length is more than six kilometers out of 19 kilometers of the route of the bridge structure. In total, more than 50,000 tons of steel structures of the road bridge will be installed in these sections,” said the head technical service LLC "SGM-Most" Yuri Beskov.
The roadbed is assembled like a children's railway, only a giant one - from many identical fragments that are joined to each other. Since the work is carried out over water, it would be difficult to lay each new span in front. Except with the help of aviation. They use a different technology. The spans are docked at the back, and then the entire structure is pushed forward - the so-called "sliding method".
"Sliding" is the following process: the superstructure is lowered onto "sleds" that slide along the slipway. And from the rear, pushing jacks are installed. They push the superstructure into the sea, and it gradually reaches the fairway. Thus, we will “advance” about two kilometers,” explains Sergey Alekseev, Deputy Director for Production at the construction site of the Crimean Bridge.
The method is complex but reliable. At the same time, new supports are being built ahead. That is, the work is carried out in parallel - it's faster.
“The work on concreting the bridge supports continues. And superstructures will be slipped onto the finished supports. This technology allows us to fulfill all the assigned tasks with high quality and on time,” says Vladislav Safin, Deputy Head of FKU Uprdor Taman.
Supports - different heights. The difference is up to thirty meters. In total, the Crimean bridge will stand on six hundred legs-supports. Seven thousand piles will be driven into the ground and the seabed. About half of the work has already been done. This is how the bridge across the Kerch Strait will look like in the end - a computer model. Road and railroads combined into single system. The first cars from the mainland to Crimea will pass in December 2018, the first trains - in December 2019.
The builders have begun the construction of the railway spans of the Crimean bridge over the waters of the Kerch Strait. The process started on the section between the island of Tuzla and the fairway of the Kerch-Yenikal Canal. A section of the bridge over 2 km long will be formed here, which will connect with the arch.
The spans are installed above the water by the longitudinal sliding method, which is widely used in modern bridge building. The structures are assembled from prefabricated blocks at the stand on Tuzla Island and alternately pushed along the sliding devices onto the finished supports with jacks. The speed of movement at this stage is about 45 millimeters per minute. In a similar way, the roadbed of the Crimean bridge was formed on the offshore sections.
“In parallel, two branches of railway spans stretch over the sea. One - for the movement of trains towards the Crimea, the second - for the opposite direction, towards Taman. Each branch is pushed by two to four powerful jacks with a force of 500 to 1000 tons. With an increase in the mass of metal moving over the water - in total, 30 spans are to be assembled and mounted on this site - the number of jacks is increasing in each direction, ”said Dmitry Petukhov, Deputy General Director for Production at the construction site of the Crimean Bridge.
The railway span of the Crimean Bridge is a prefabricated metal structure weighing 580 tons, including more than 40 main elements. They are connected to each other by welding and high-strength bolts. The height of the block assembled from the factory segments is more than 5 m, the width is more than 15 m, taking into account service aisles. The spans are installed on marine supports, the distance between which does not exceed 65 m.
“Each subsequent support is about half a meter higher than the previous one. The railway bridge gradually “grows”: from 5 meters it begins to rise higher and higher on the island of Tuzla, so that the height of the supports reaches almost 17 meters to the sea section, and further - 35 meters above the fairway of the Kerch-Yenikal Canal. Such a smooth rise will ensure a comfortable and safe entry of passenger and cargo trains to the arched span, under which ships can pass freely,” said Yury Beskov, head of the technical service of the SGM-Most company.
In 2018, work on the construction of railway spans will be launched in all offshore sections. In general, more than 6 km of railway metal structures will be pushed over the Kerch Strait between 64 supports. The total mass of sea spans for the railway will be more than 60,000 tons.
The builders have completed the next stage of the construction of the Crimean bridge - the assembly of the span structures of the road part, having completely formed the bridge deck from the Taman coast to the Kerch coast. A string of metal structures with a total weight of more than 100 thousand tons is stretched over the Kerch Strait between 288 supports. In the next construction season, the road workers will “dress” the Crimean bridge in asphalt concrete and by the end of 2018 will prepare for the start of the movement of cars.
The last meters of the spans that closed the bridge deck were pushed from support No. 254 to fairway No. 253. This is a segment of the offshore section from the fairway towards Kerch, one of the most difficult in the project. The track here makes a turn, rounding Cape Ak Burun. Such a trajectory is adopted in the project for the preservation of the historical heritage monument "Kerch Fortress", located on the cape.
The construction of spans over the water area was carried out using the method of longitudinal sliding: the segments were enlarged on the slipway, then they were moved towards the fairway using powerful jacks. At the same time, for more than a kilometer, the thrust was not carried out in a straight line, but in compliance with the design radius.
The total weight of the spans, pulled by a single thread between 34 sea pillars from the Kerch coast to the fairway section, reaches almost 20 thousand tons. To create them, it took more than 4.5 thousand different elements: beams, orthotropic plates, consoles. They are connected with almost 300 thousand high-strength bolts and nuts, the length welds in this area reaches almost 30 km.
In general, the bridgebed of the road part of the Crimean bridge is a thread almost 17 km long (another 2 km on the Kerch coast the road goes along the embankment). Of these, more than 6 km pass over the sea area, gradually rising from 5 meters to 35 meters above the fairway of the Kerch-Yenikal Canal. The arches of the Crimean bridge are installed here, under which ships pass freely.
Having connected the bridgebed under the road, the bridge builders completed production program 2017. On the this moment According to the project of the Crimean bridge, a significant reserve has been formed in a number of areas. Bored and prismatic piles were driven in full, tubular piles – by 95% of the project (almost 5,100 pipe piles were driven by the end of the year, which is more than 330 km of steel pipe). 455 supports out of 595 provided by the project are ready (including all 288 supports for the road).
In 2017, the formation of pavement began on the finished sections of the bridge. The pavement of the Crimean Bridge almost along the entire route is two-layer with a total thickness of 11 cm (three-layer at the interface along the banks of the Kerch Strait). The asphalt concrete mixture is prepared using bitumen modified with polymer additives - a modern binder. It makes the coating more durable, durable, resistant to deformation and cracks. Optimum mixture composition and high degree of compaction guarantee strength, long service life and water resistance of the coating.
By the end of the year, asphalt concrete pavement was completed in the amount of 50% of the design. So, the lower layer of asphalt is completely ready in both directions of the road from the Taman coast along the Tuzlinskaya Spit, which is almost 4.5 km of the route (the upper layer in this section is 80% ready). The readiness of the roadway on the longest land section - along the island of Tuzla - is about 70% on the lower layer and more than 30% on the upper one. Asphalt laying on the sea spans will begin in 2018.
The technology for constructing the roadbed in the areas located near the expansion joints has been successfully developed. Such seams are metal structures with a rubber "accordion", which exclude deformation of bridge spans at the junction in the event of temperature changes or seismic loads. The task of the road builders is to form the most even surface of the roadway so that the asphalt “merges” with expansion joints so that the motorist does not feel any discomfort when crossing them. By the end of the year, more than 130 expansion joints out of 190 design ones were completed.
Along with the continuation of construction and installation work, builders are further arranging the road part. This is the creation of a power supply network, water disposal systems, lighting, and the construction of a barrier fence.
Another task for 2018 is the creation of an automated control system road traffic(ASUDD), designed to manage traffic flows, as well as the maintenance of the highway. Such a system will, among other things, promptly inform drivers about the state of traffic on the highway through the Kerch Strait, for example, about difficult road conditions. Data will be output through several variable information boards installed on the bridge.
In addition to ASUDD, the Crimean bridge will be provided automated system power supply management and monitoring system engineering systems and designs. Information from all these systems will be accumulated at the Central Control Center located on the territory production base operational service. Work on the construction of the base is already being completed on the Taman coast.
At the same time, builders continue to work on the railway part of the Crimean bridge, which will be opened to traffic in 2019. More than half of all supports for the railway are ready. The pre-assembly of the superstructures was completed by 20% of the project. Before the end of winter, the builders plan to start building spans for the railway over the waters of the Kerch Strait.
They are interested in different things: some want to know if the wind will not interfere with cars moving along the bridge, others care about who will be the first to be lucky enough to step onto the finished bridge, however, probably the largest group of “interested ones” are those who observe technologies and engineering operations building of the century. For them, journalists have prepared this article. About the uniqueness of the bridge sounded more than once. Journalists admired, experts - confirmed the facts. , work on reinforcement, concreting and construction of foundations for supports in offshore areas - these operations have not yet been done in Russia.