Due to theft and design mistakes, the bridge gradually collapses
“The grandiose construction of mankind”, “a masterpiece of design thought” is just a small fraction of the enthusiastic epithets that accompanied the construction of a bridge from Vladivostok to Russky Island. Officials and builders exclaimed patriotically: “Finally, we will rub our noses for all these Chinese and Americans. Our bridge will be the largest, most beautiful, and it will be built using innovative technologies (which ones and what they are, however, was not specified).
The largest, most modern
Without exaggeration, this bridge can be called the “construction site of the century”. For example, during its construction, a unique inclined formwork was used to construct the pylon grillage, the length of which was 320 m. The pylon grillage itself was divided into three sections, in each of which a complete concreting cycle took place. The volume of one such site was 9 thousand cubic meters of concrete, which in scale is equal to the construction of six monolithic houses of 10 floors. And in terms of the volume of material used, the foundation of the pylon on the island is equal to the whole microdistrict, while the span (of the steel structure) is 21 m, and the under-bridge dimension is 70 m.
For reference: bridge to Russky Island - the largest cable-stayed bridge in the world. Traffic on it was opened on August 1, 2012. The bridge was built for the APEC summit, which took place in September 2012, and connects the mainland of Vladivostok with Russky Island through the Eastern Bosphorus Strait. The central span of the bridge with a length of 1104 m is a record in world practice. The total length of the crossing is 3.1 km, the height above the water level is 70 m.
Metal was stolen by the tons
However, one should not forget that a bridge was being built in Primorye, and in those parts of the world, governors and high-ranking officials are often imprisoned for bribes. So at the "construction site of the century" cunning people decently "warmed up their hands." It took only 4 months after the opening of the bridge, and it turned out that during its construction, metal structures worth more than 96 million rubles were stolen. The suspect is a security officer of the Mostovik company Rafael Javadov... He created an organized group, which included workers from the checkpoint, who freely passed certain vehicles, and storekeepers who had free access to metal. Javadov even acquired special equipment for the removal of the stolen and appointed a resident of the city who had been previously convicted of kidnapping as a driver. The stolen goods were handed over to metal collection points in Vladivostok.
The bridge is held on parole
Less than a month passed, and it turned out that the outer shell of the bridge cable had "sagged" due to weather conditions. However, the administration of Primorye, with reference to specialists, states that these changes will not affect the safety of the structure in any way.
Meanwhile, the former deputy head of Rosprirodnadzor Oleg Mitvol admitted that the bridge shrouds had sagged too much, which corresponds to the 40th or 50th year of operation, that is, "so they could sag in half a century."
Oleg Mitvol believes that initially, at the stage of the project, an incorrect constructive decision was made. He calls for the designers of these structures to be prosecuted and reimbursed for budgetary costs. “However, I do not know how they will recover the multi-billion dollar costs. In an amicable way, all this must be disassembled and done again. This is a disgrace ", - considers Oleg Mitvol. And many builders agree with him. They insist that it is necessary to change the very approach to construction, especially of such large objects as bridges.
The general contractor was not allowed to the project
This is how, for example, construction is carried out abroad. First, a project is developed on paper, charts, in technologies, everything is calculated, and only then we are talking about cash injections. And in our country, funding is first knocked out (as a rule, it is state), while the "beaters" often do not even have design documentation, working drawings. When the first funds arrive, an agency is chosen to draw the details, the concept, for example, how long the overpass will be, etc. After the "bridge is built" on paper, it is necessary to undergo an examination. It is usually formal. Specialists who would be versed in construction and technologies to the subtleties are not present there. Therefore, usually no one thinks about how to build spans, beams, felons. In order to pass the examination, you need to lay down the approximate cost of the project (it is usually greatly underestimated and does not include technology costs). When the examination has been passed, the work of the designer begins. Moreover, general contractors and contractors do not take any part in the project. They are given a ready-made solution. The contractor begins to work on it, and then various "blunders and shortcomings" emerge, for which he is now responsible. And such "mutual responsibility" exists only with us, even our CIS neighbors do not have such lawlessness.
"Sprinkled with stability"
Vladivostok knows firsthand what such serious errors lead to in the construction of such large objects. So, in June last year, a section of the new Sedanka - Patroclus route began to collapse. Rocks and dirt collapsed into the garages below. According to investigators, the total damage amounted to almost 1.8 million rubles. And 2 months later, as a result of a landslide, a section of a retaining concrete wall collapsed onto the same highway, which just leads to the bridge to the Russky Island.
“Do not be afraid, we just sprinkled a little with stability,” - the locals joked.
A landslide descends on the Sedanka - Patroclus highway
The perpetrators were quickly found - CJSC Pacific Bridge Building Company, which is also building a bridge across the Golden Horn in Vladivostok, accused the designers. Chief project engineer of the road department of the Khabarovsk branch of "GiprodorNII" Alexey Mikhailov stated that the builders had not made the drainage system, which was in the plan. The designers determined its absence only by looking at the track after the collapse.
They built, they built ... and for whom was they built?
The bridge was built, the summit was held - and what next? It was supposed to open a federal university on the island. But who will study there? Young people and teachers are in no hurry to leave the mainland. “There is not even drinking water, it is not known in what conditions we will live,” one of the students complains.
Indeed, drinking water is brought to the island in cans. And it is still unclear when the water pipeline will be built in Russkoye. In the meantime, water for technical needs is produced by a desalination plant.
The inhabitants of the island say that heating is not supplied to some buildings of the future university, it is not even provided for in the project. For example, they jokingly call building No. 7 a "float", since it was erected at the site of the groundwater outlet and its foundation is constantly flooded.
Civilization smells bad
Not so long ago, a prosecutor's office was opened on the island to make it easier to receive applications from disgruntled builders. And the indignant inhabitants of the island, it seems, do not hear. They are trying to convince the Crocus company, which has built the FEFU buildings, to change the sewerage system. According to the project, all sewage discharges after cleaning will fall into the closed Novik Bay, located in the middle of the island. For ecologists and hydrologists, it is obvious that given the volume of discharge, in a couple of years fresh water will displace sea water. The fauna of the bay will be the first to die - fish, delicious mollusks, sea cucumbers, then algae, seaweed. And then the bay will turn into a swamp.
Representatives of the Crocus company in their defense put forward an argument, they say, there used to be a desert here, and we built it up and brought civilization to these desert lands. But local residents do not need such progress. They want to breathe clean air, not ... you know what.
Elena Pryadkina
The Russian bridge in Vladivostok is cable-stayed and connects the Nazimov Peninsula and Cape Novosilsky on the Russian Island, separated by the Vostochny Bosphorus Strait. The bridge appeared in the framework of the APEC summit in 2012. The Russian bridge is a complex and unique object in the entire practice of bridge building in Russia and the world.
Construction
The Russian bridge in Vladivostok began to be built in September 2008, although the question of its construction arose at the beginning of the twentieth century. In 1939, the first draft was drawn up, in 1960 - the second. But both remained unfulfilled. And only in 2008 the final design of the cable-stayed bridge was approved.
During the construction of the bridge, different positions were expressed regarding the advisability of its appearance. Some said that the work was economically unjustified, since only five thousand people live on the Russky Island. Others insisted that the construction of a bridge to the Russky Island would be an impetus for the development of the island, the creation of large economic and cultural centers.
Description
The Russian bridge is one of the most grandiose in the world. One of the reasons for this is that the length of the bridge in Vladivostok on Russky Island – more than three kilometers. The roadbed of the structure is supported by diagonal cables. They, in turn, are attached to two pillars, each reaching a height of 324 meters.
The entire structure weighs 23 thousand tons. Its spans reach a kilometer. On top of the bridge, you can see the stretched cables painted in the color of the Russian flag. Lanterns are installed along the railing. At the descent from the bridge you can see the cannons - the remains of the Novosiltsevskaya battery.
There are hidden staircases inside each pylon that lead to the observation decks, but they are only accessible to the staff watching the bridge, and only occasionally to photographers. A breathtaking view opens up from a 300-meter height: the endless Pacific Ocean and Vladivostok below in barely noticeable outlines
Technical features
The cable-stayed system of the bridge across the Eastern Bosphorus was designed by the best engineers in Russia and abroad. The cables consist of 13 to 85 parallel strands, each individually protected against corrosion. The casing is made of two layers: the inner one is made of dense polyethylene, the outer one is thinner.
The decorative shell has a spiral bead - it provides protection against vibrations generated by the simultaneous impact of rain and wind.
The Russian bridge was built in conditions of strong winds, a humid climate and sharp temperature changes. As a result, the cables, thanks to special steel, are able to withstand the temperature range from -40 to +40 degrees, and their service life is up to one hundred years. The aerodynamic section of the structure makes it resistant even to the squally wind that often occurs in Vladivostok.
Traffic
The bridge to Russky Island allows residents to travel there for the weekend. The structure is designed for light vehicles and small trucks.
There are four lanes on the carriageway - two in both directions. Drivers, who find themselves at a height of 70 meters, are breathtaking from the water surface extending below and the shrouds hanging from above. Pedestrians are not allowed to enter the bridge.
Lighting
Lighting equipment for the bridge to Russky Island was completed in early 2013. The main task of the illumination is to create the illusion of a bridge floating in the air and emphasize at the same time its main elements - giant supports and cables, painted in the colors of the Russian flag.
The lighting equipment is fixed in such a way that it does not create difficulties during operation. Lighting not only illuminates the bridge, but also visibly transforms its appearance in the dark.
Bridge for tourists
Bridge to Russian was called "useless construction for $ 1 billion"
The bridge to the Russky Island in Vladivostok has been criticized from the very beginning of construction. Some experts questioned the feasibility of such a grandiose project. Another "fly in the ointment" was added by the analyst of the Center for Economic and Political Research (EPICenter) Alexei Mikhailov.
WHY DO I NEED IT?
The cable-stayed bridge, like its Golden “brother”, which connected the city center with Cape Churkin, to Russky Island was built in preparation for Vladivostok for the APEC summit. The building is unique. After all, the Russian Bridge - and this is its official name - has the world's largest span among cable-stayed bridges, 1104 meters long, and the first pylons in height are 324 meters.
Economist Alexei Mikhailov cites other impressive figures: the construction cost is about $ 1 billion. The same amount was spent on the access road to the airport and the city.
This cable-stayed bridge is actually very beautiful, soaring in the air with a central span of more than 1 kilometer at a height of 70 meters, which is supported by two pylons 324 meters high. Probably, he is grandiose in engineering decisions. And it will certainly become now a new symbol of Vladivostok. Just ... why is it needed? - the expert asks.
The main argument "against the bridge" from the analyst is the same as that of many critics of the structure - it has a small capacity, and the island's population is too small for such costs.
A bridge with a capacity of 50 thousand cars a day leads to a small island of Russkiy with a population of 5 thousand people. And even those mostly poor fishermen living in barrack-type houses do not have cars, - says Mikhailov.
In contrast to this criticism, the Vladivostok authorities have repeatedly stated that the bridge was built, including for the development of the island, the program of which includes the construction of many large facilities and the creation of infrastructure for 150 thousand people.
THE BRIDGE "DOES NOT PAY OFF"
What's next with Russky Island? Now there are the same 5 thousand residents without cars. In all honesty, was it really worth spending $ 2 billion to access the beaches by car? Can't you get there by ferry? After all, every two hours he walks and even transports cars, it's not so expensive, - the expert continues.
The development of tourism, the construction of new housing on the island is one thing. But, perhaps, the main argument in favor of the expediency of the bridge was the FEFU under construction on the same island. After all, it was planned that the united university would become the largest educational institution in the country and even in the world. Students from all over the planet will come to study there, and the best foreign teachers will teach. However, the contractor did not manage to finish building the FEFU buildings. And the great "resettlement plan" failed, and the students stayed on the mainland, at least until construction was completed. Now only nonresident students live on the island, who every morning go to classes in the city.
To all this can be added the absolutely undeveloped road infrastructure of the island. After leaving the bridge, you find yourself on the real "Russian roads", having driven along which you need to resort to car repair services. Therefore, most of the townspeople do not dare to go there. And taxi firms raise prices for trips to the island - up to 1,000 rubles from the center of Vladivostok.
Alexei Mikhailov compares the bridge to Russky with his “colleague” Golden Gate in San Francisco, USA. Only not in favor of the first.
They are similar in their main characteristics. But Golden Gate was built 75 years ago, is paid and actually allows 120 thousand cars a day. This bridge literally makes half a million dollars a day. Is the Russian Bridge free, and how much will it actually allow per day after the APEC summit is over? A couple of thousand cars? Or maybe a couple hundred? - the expert writes.
However, it should be noted that neither the bridge builders nor the Primorye authorities share the economist's opinion.
It will be a comfortable area of \u200b\u200bVladivostok, very convenient for living. Children will be able to go to school here, then to the university - and there will be no need to travel anywhere. As for the other territory of the island, it is planned to leave it under a tourist and recreational zone, - the governor of Primorye believes. Vladimir Miklushevsky. - Only the coast will be built up - we are talking about boarding houses and rest houses. Still, the nature of the island must be preserved as much as possible for posterity.
Take a look at any photograph, tourist avenue: if there is a bridge in the city, then it will certainly be on them. The bridge is a kind of monument, an architectural decoration of the city, an achievement of its inhabitants. San Francisco - Golden Gate, New York - Brooklyn Bridge, Hong Kong - Stone Cutting Bridge, - the director of the branch of USK MOST OJSC in Vladivostok expresses his opinion Alexey Baranov. - And one more indisputable advantage, purely practical. By connecting the mainland with the Russky Island, the bridge opened up new development prospects. Many cities in Russia, including Vladivostok, suffer from heterogeneity of style: in different periods, under different governments and cultures, they were built differently and did not always care about compatibility. And the facade of the city should be planned in an amicable way once and for all, only then it will be beautiful. Of course, the city cannot afford to rebuild the existing quarters. But in Russky there is a chance to start with a clean slate, resulting in a large and harmoniously built up area, very promising for development.
BTW
The question of building a bridge to Russky Island was raised in the first half of the 20th century. The first project was completed in 1939, the second in the 1960s. However, neither one nor the other was implemented. In early October 2007, NPO Mostovik won a tender for the design of a bridge crossing to Russky Island. The contractor was USK MOST OJSC. The construction of the bridge began in 2008, on July 1, 2012, Prime Minister Dmitry Medvedev opened the bridge to workers, and a month later, on August 1, the bridge was also opened for personal transport.
The bridge to Russky Island across the Eastern Bosphorus is being built as part of Vladivostok's preparation program for the 2012 APEC summit. The cable-stayed bridge will connect the mainland and insular parts of Vladivostok and will become an important link in the transport system of the Primorsky Territory. The bridge will become the world record holder for the length of the central span - 1104 meters and the length of the cables - 580 meters. The height above the water mirror is 70 meters. The height of the pylons is 324 meters.
2. At the beginning of October 2007, NPO Mostovik won a tender for the design of a bridge crossing to Russky Island. The main partner of the association in the implementation of design work was the design organization CJSC "Institute Giprostroymost St. Petersburg"
3. Construction of the bridge began in September 2008. The general contractor for the construction is USK Most OJSC. The main subcontractors were SK MOST OJSC and NPO Mostovik LLC.
4. The bridge will open to traffic in July 2012, and in September Russky Island will host delegates to the summit of the Asia-Pacific Economic Cooperation Organization.
5. The total length of the bridge is 1885.53 m (of which 1104 m is the central channel span)
6. The approaches to the bridge are overpasses with a total length of more than 900 meters. Trestle supports are rack-mountable, from 9 to 30 meters high. Spans are made of steel-reinforced concrete, consisting of metal boxes with inclined walls and a monolithic reinforced concrete slab.
7. The width of the carriageway is 24 m. There will be 4 lanes of traffic (2 in each direction)
8. For the construction of the M6 \u200b\u200bpylon on the Nazimov peninsula, an artificial peninsula was dumped, from which wells were drilled for supports. The construction of the pile foundation of the M7 pylon on Russky Island began with water on a temporary working metal island. They are designed to protect against bulkheads of ships with a displacement of up to 66,000 tons, ice movements and wave action. The total volume of rock and loose soil moved during the construction of technological sites is 1.5 million cubic meters.
9. The superstructure has an aerodynamic cross-section to accommodate squally wind loads.
10. At the base of each pylon there are 120 bored piles with a diameter of two meters. Piles with a non-retrievable metal shell under the M7 pylon go down to 46 meters. On the Nazimov Peninsula, the maximum depth of reinforced concrete piles is 77 meters.
11. For the construction of each pylon grillage, it took about 20,000 cubic meters of concrete and about 3,000 tons of metal structures. Tensor sensors are built into the grillage body to monitor the state of this colossal foundation.
12. The height of the pylon is 324 meters, which is commensurate with the height of a 90-storey building.
13. Top of the pylon
14. Delivery of builders to the pylon is carried out by cargo-passenger lifts. In the photo, the German GEDA lift with a lifting capacity of 2 tons, which allows you to simultaneously transport up to 24 people. Lifting speed 65 m / min.
15. Builders worked in extreme weather conditions. The wind speed reaches 36 meters per second, the storm wind raises waves up to six meters, the ice thickness reaches 70 centimeters. The temperature in winter drops below minus 36 degrees, and rises to plus 37 in summer.
16. Continuous reinforcement and concreting of the M6 \u200b\u200bpylon (Nazimov Peninsula) were overcome in a record 25 months.
17. The mortar was supplied to such a height by special concrete pumps.
18. View from the tower crane Potain MD 1100 Up to this mark 348 meters from the ground. As I was told, at the moment, this is the tallest tower crane in Russia.
19. Lift height - 335 m, boom length - 60 m.
20. Maximum lifting capacity - 50 tons
21. SK Most uses Kroll tower cranes with a lifting capacity of 40 and 20 tons.
22. Crane operator "thousand-man"
23. Potain MDT 368 tap (). Maximum lifting capacity - 16 t, lifting height - 328.7 m, boom length - 40 m.
25. The stiffening beam of the central navigable span of the bridge is all-metal.
26. It is a single box for the entire cross-section with a lower and upper orthotropic plate and a system of transverse diaphragms.
27. The metal stiffening beam consists of 103 panels 12 meters long and 26 meters wide. The total weight of the panels is 23,000 tons. The length of the stiffening beam is 1220 meters.
28. Large-scale assembly of panels was carried out on the territory of the production base on the Nazimov Peninsula ("Mostovik") and in Nakhodka ("SK Most").
29. Large-scale sections for the installation of the central superstructure in specially designated "windows" were delivered by barges to the assembly site and lifted by cranes to the 76-meter mark, where the cables were docked and fastened.
30. For the joints of the vertical walls of the blocks, longitudinal ribs, transverse beams and diaphragms, assembly joints with high-strength bolts are used.
31. "Bridge" on one side ...
32. ... and "SK Most" on the other Derrick cranes of Russian production with a lifting capacity of up to 400 tons
34. On the night of April 12, 2012 - the builders completed the installation of the final locking panel of the span, which connected the shores of the Eastern Bosphorus.
35. More than 300 people worked on the docking of the last panel.
36. For the construction of a bridge to the Russkiy Island, a special welding procedure has been developed, which is much more stringent and complex than for other bridge crossings. Each seam is checked with ultrasonic testing devices.
39. On the bridge over the Vostochny Bosphorus, an improved system of cables is used with a denser arrangement of strands in the shell. The weight of the cable-stayed system is 3720 tons, the total cable length is more than 54 kilometers.
40. Shrouds are composed of parallel strands that are individually protected against corrosion, the number of which ranges from 13 to 85.
41. Each such strand consists of seven galvanized wires, sheathed with high density polyethylene.
I am citing an article in the newspaper "Khabarovsk Express". It turns out that the astronomical sums allocated for the Potemkin village were stupidly plundered, and the built miraculous bridge and other mirages would collapse, burying thousands of people. The question arises: is the situation with the Olympic construction in Sochi the same? The conditions are, in principle, the same: a lot of money and a lot of crooks.
From the editor.
The author of the article has previously raised the topic of the safety of unique bridges in Khabarovsk Express. I contacted Rosavtodor, Rostekhnadzor, the Prosecutor General's Office, the Embassy, \u200b\u200bthe President of the Russian Federation. In response, having made a bureaucratic circle, they received complacent replies. The unreliability and technical neglect of the main objects of the APEC summit was highlighted two years ago by the suicide of engineer Vyacheslav Polyanskikh. He committed suicide right in the bay where he was building the bridge. There was a suicide note: “The bridge is being built with gross violations. I do not want to be extreme when the bridge collapses and there will be a mass of victims ... "
"Khabarovsk Express", No. 43, 26.10.11
APEC Summit Bridges: Russian Roulette
Gross violations of the norms for the design and construction of bridges to Russky Island and across the Golden Horn Bay in Vladivostok, bordering on a crime, have already been described in many of my publications. The facts published by me, which are officially documented in the reports on monitoring the quality of work, convincingly prove: the reliability of the foundations of the bridges and the durability of concrete are not ensured. Simply put, monitoring materials are a verdict: according to the law, bridges cannot be taken into operation and traffic can be opened on them - they can collapse at any moment!
One of the reasons for such a state of bridges, I believe, is that the office of the plenipotentiary of the President of the Russian Federation in the Far Eastern Federal District evaded control of the implementation of urban planning legislation on bridges, instructing the customer to control himself, and this is prohibited by Part 6 of Article 8 of Federal Law No. 59.
And not so long ago, the plenipotentiary suddenly announced: “For some objects of the APEC-2012 summit, the work schedules, unfortunately, do not quite take into account the natural and climatic conditions - rain, fog, wind, so there is a slight lag. And if the bridge to Russky Island is not completed by the deadline, then there is no tragedy in this ... "
The Internet responded to the application in different ways. “They are tricky at the embassy - most likely they realized that Ryazanov was right about the unreliability of the bridges. Continuing to violate, we would have met the deadline ... ”. “No need to pump up. The task is not for all sorts of officials to cross the bridge in Mercedes, but to master new technologies and become a real bridge power. "
About "power" is firmly said! But the customer (Rosavtodor), starting with the survey, did little to ensure the reliability of these unique cable-stayed bridges (the largest span in the world, 1100 m). First of all, this concerns the bearing capacity of foundations, as well as the durability of concrete.
And the "experts" (in quotation marks) who build these bridges believe that only one concrete characteristic is sufficient to assess the reliability of structures - strength. And the fact that concrete should and can be guaranteed to be an eternal material, in the literal sense, they seem to have "not passed" in the university.
At one time, our country adopted the standards of the Council for Mutual Economic Assistance (CMEA), requiring the provision of 0.95 characteristics of materials and 0.98 confidence probability for soils, taking into account possible changes during construction and operation.
Were published: GOST "Reliability of building structures and foundations" (total 8 pages) and GOST "Concrete. Strength control rules "(20 pages in total). Links to them are given in my publications.
But, apparently, the “specialists” who build APEC bridges do not know these requirements. Here is their response on the Internet forum: “Have you ever seen or heard that Ryazanov? An old senile who remained to live in the last century, denying modern achievements, claiming that the most reliable was in the 70-80s! "
The author of the venomous response right there, on the forum, was dubbed "a young senile". Where he could see or hear something, if the last 30 years, using my inventions on all the bridges of the Far East, the designers, contrary to the law, did not refer to these inventions (more than 150 publications and books, including “Columnar foundations and supports of bridges ... "- Khabarovsk, 2009, 452 p.). The "old senile" was repeatedly lowered into the wells under the pillars to a depth of 25 m, so that it would be safe for young marasmatics who did not study the foundations to travel safely.
Such "amateurs from bridge building", apparently, do not understand the required standards (the class of concrete is the strength guaranteed by homogeneity). Having bought equipment, they illiterately adopt foreign technologies.
Obviously, they do not have enough education to understand the need for automatic dosage of the components of the concrete mixture - depending on the moisture content of crushed stone and sand (indeed, the rains, fogs and humidity of the seaside air mentioned by the plenipotentiary are affected).
As the monitoring of the quality of the construction of bridges has shown, with cast concrete mixtures, young senile people ignore the GOST requirement to ensure the class of concrete "with a minimum consumption of cement." Those. they overestimate the strength of concrete due to the higher content of cement. But this is criminally dangerous - concrete becomes frost-resistant! Here, after all, it is not France or Spain, but the harsh Far East.
Let us give an example of the "professionalism" of the candidate of technical sciences - the head of the control department of the directorate for the construction of the bridge on Russky Island, as well as acting the head of another department (they say, "hereditary bridge builder", but with the formation of a general construction technical school).
In a certificate dated August 21, 2009, our monitoring group of experts listed the documented violations: “The composition of the concrete mixture was selected only by laboratory means - without checking the characteristics of the homogeneity of concrete in terms of strength. There is no reason to assess the reliability of structures in accordance with GOST 27751-88 ... "
However, in their “Explanations”, the heads of departments write: “We consider the absence of grounds to be far-fetched, since acceptance of concrete is carried out in accordance with clause 5.2 of GOST 18105-86, ... if the actual strength of the concrete is not lower than the required strength. "
This stupidity is echoed by the head of the State Construction Supervision Department of the Federal Service of Rostechnadzor (letter dated December 15, 2010). It turns out that the GOST standards are “far-fetched”: the “required strength” is established in accordance with the “achieved uniformity”.
Having undertaken the design and construction, such "specialists" probably did not know that, taking into account the control of the frost resistance of concrete, to select the optimal composition according to GOST 18105-86, a preparatory period would be required, and at least a year! We could speed up the matter by using computer programs for the prompt selection of the composition of the concrete mixture. As far as I know, they have not used it.
As if justifying such familiarity with GOST, the general director of USK MOST, the general contractor for the bridge on Russky Island, introduces a new concept into the characteristics of concrete strength. Not a “brand” (used until 1985) and not a “class” that the old senile people introduced in accordance with the CMEA standard, but a certain concept of “class brand” - “B60 brand.” * Sorry for being straightforward, but it borders on sabotage.
"Class grade" abolishes the concept of "security", which characterizes the strength class of concrete. The control of the homogeneity of concrete strength is eliminated. The practice of adjusting the laboratory selection of the composition of the concrete mixture in production conditions is canceled.
Finally, the concept of “concrete grade in terms of frost resistance F -… the number of freezing and thawing cycles of concrete samples tested according to the basic method” (GOST 100060.0-95) is discarded. What else did the "old idiots" want - after all, it takes six months to control only one batch of concrete samples by the basic method! And we have APEC-2012 - deadlines!
Young senile people, subverters of norms and standards, trumpet loudly that their bridges will last forever. A fresh legend: such low-quality concrete will last a maximum of twenty years. And after the delivery of the bridge, it will soon be necessary to put it on reconstruction.
In addition to the durability of concrete, the reliability of the bridge in accordance with the current standards can be ensured by calculating the foundations according to the characteristics of the soils, which were obtained during the survey with a high confidence level - in terms of strength 0.98 and deformation 0.9. We also need reliable statistics of test results, at least six soil samples from each geotechnical element (soil layer).
Meanwhile, on pylon No. 9 of the bridge over the Golden Horn Bay, the prospectors located all exploration wells on the shore, outside the foundation! The characteristics of the rocks (for example, the weathering coefficient) were not determined at all - for all wells, chokhom, they were established by surveys at a depth of minus 10.5 m.
The distance between the pillars, on which the pylon (support) of the bridge rests, is allowed by the norms of at least 1 m. Because the soil around the pillars, taking into account the methods of well development, loosens and becomes loose. But on the pylons of the bridge over the Golden Horn in such an unreliable soil, the project provides for a distance between the pillars of only 0.75 m.At the same time, the authors of the project have frivolously dispensed with the obligatory characteristics of soils, and the main violation is that only vertical (top to bottom) loads on giant bridges, i.e. as for country sheds.
And what about the most dangerous - horizontal, lateral moments and loads? Any engineer familiar with the basics of structural mechanics will understand that, without the characteristics of the soil between the pillars, it is impossible to calculate the grillage (pylon base). The actual difference in the depth of the pillars turned out to be more than 13 meters - with an allowable norm of 25 cm! Deep pillars, being in an elastic medium, can be included in the work on horizontal loads only when rigid short pillars embedded in the rock lose their stability - they collapse.
Storm winds, at the upper points of bridges, at an altitude of 200-300 m, reaching a speed of 95 m / s; temperature differences between subtropical summer and sharply continental winter; the braking force of the machines transmitted to the bridge deck - any factor can cause the pillars to roll. And then even the most insignificant rolls will irreversibly lead to horizontal displacements of the top of the pylons (geometry in the volume of high school), and therefore the pylons can collapse at any moment.
Hence the question: just such "modern achievements" of unreliability of foundations, "development of new technologies" to reduce the strength of concrete will help us to become a "real bridge power" ?!
