Bridges, viaducts, flyovers, viaducts. What is the difference? April 3rd, 2017

These words denote very similar constructions, so they are often confused. For those who want to understand a little popular science engineering with pictures for clarity.

Bridge
Since ancient times, people have built bridges to overcome water barriers - rivers, lakes, swamps. The first bridges were built several thousand years ago. Therefore, the word "bridge" is not only the most used, but also the oldest; in broad sense almost all other structures (overpasses, viaducts and viaducts) are bridges. By the way, in the title picture there is a picturesque bridge on Atlantic road in Norway.

The oldest existing bridge is the Ponte Milvio in Rome. It is over 2000 years old: it was first built in stone in 109 BC.

Most long bridge in the world - the Qingdao Bridge, 42.5 kilometers long. It connects the Chinese mainland port city Qingdao with the island region of Haundao in Jiaozhou Bay.

And the bridge under construction to the Crimea through Kerch Strait with a length of 19 kilometers will be the longest in Russia.

The widest bridge in the world is located in St. Petersburg. This is blue bridge across the Moika River. Its width is 97.3 meters, which is almost three times its length.

Bridge type overpass
This is a structure that is being built over another road, road or rail. It is technologically seriously different from the bridge, which is why it is called differently. The main difference is much simpler supports; after all, when designing an overpass, it is not necessary to take into account the watercourse, ice drift, erosion of supports and the possible bulk of passing ships, which bridge designers have a headache about. In general, an overpass is a bridge over an ordinary road.

The routes are very different. This is a single-span overpass on Electrolitny Proezd in Moscow.

And this is an overpass on the "small concrete road" at the White Pillars in the Moscow region.

viaduct tunnel type
Some short tunnels are also called viaducts! Usually this is the name of the tunnels, over which the span of the overpass lies, and the length is greater than the width of the span, but less than 300 m.

An example of a tunnel-type overpass under a railway Gorky direction in Pavlovsky Posad.

overpass
The construction of an overpass usually requires 2-4 spans of 10-30 meters each, but more are needed to lay an overpass. In fact, this is the main difference between these engineering structures. But there are others: the overpass only crosses the road, and the overpass can cross several types of obstacles at once - it can be a river, a highway, and railways. That is, the flyover may well combine in this way a bridge and an overpass.

The longest overpass in the world is the Bang Na Highway in Thailand, 54 kilometers long.

And this spiral overpass had to be built because of the tenants of a high-rise building in Guangzhou, China, who refused to move.

Viaduct
In addition to roads and reservoirs, there is another type of obstacles - relief, that is, ravines, gorges, hollows. Bridges that are built in places with a difference in height are called viaducts. Their construction instead of conventional roads is economically justified when it is unprofitable to create an embankment. In general, it all depends on the depth of the ravine and its length on the way of the highway. It turns out that the difference between a viaduct and an overpass is the absence flat surface under the bridge! Therefore, there can no longer be the same type of supports and spans. Viaducts are usually very beautiful and majestic buildings. For example, the height of one of the pillars of the world's highest Millau Viaduct in France is about 340 meters!

Aqueduct
One more interesting building, however, not related to the roads. This is an analogue of a viaduct, only for the transfer of water, and not Vehicle, over the same ravine, river or other obstacle. Usually an aqueduct is part of an irrigation system.

Magdeburg water bridge connects the inner port of Berlin with the ports on the Rhine

Moscow Canal above Volokolamsk highway in the capital

Rostokinsky aqueduct in the northeast of Moscow

Seleduk
The road does not pass through the herring either, but it is very closely related to traffic safety. This is the name of the structure above the mountain road, which serves to pass through it. debris flow and protecting drivers and passengers. It is also called a mudflow outlet and an avalanche gallery.

Used materials:

Description and justification of the adopted design decisions

During the reconstruction of the facility, the technical category of the road changes from II to I-c, while it is necessary to increase the size of the carriageway of artificial structures to 4 and 6 lanes. Considering that, based on the results of the survey of the existing overpass, it was concluded that it was unsuitable for further operation due to existing defects (the structure has been operating for more than thirty years), due to non-compliance with standard loads, due to wear and tear of individual structures requiring replacement and overhaul, it was decided not to reconstruct it, but to disassemble and build a new one with dimensions G-2 (15.25 m + 1Tx0.75) m each.

Considered options.

The design documentation considers two options for the overpass scheme. The options for the overpass were developed in accordance with the requirements, specifications of the branch of Russian Railways, the Volga Railway No. 710 / NG dated May 27, 2013, GOST 9238-83, SNiP 2.05.03-84 * and other applicable regulatory documents.

1 option - overpass through railway with span structures 21 m and 24 m long according to the scheme 21+24+21m. The length of the overpass is 71.28 m. Considering that the overpass is located in a recess and the height of the cones is small, the abutments are assumed to be piled in relation to the TS of the 3.503.1-79 series on prismatic piles with a section of 35x35 cm. on a pile grillage. Piles are prismatic with a section of 35x35 cm.

Option 2 - overpass with a metal span structure 42 m long. The supports are taken with back walls in a tongue and groove grillage made of a metal sheet pile with a diameter of 82 cm. The slopes of the cone are taken up by a retaining wall also made of a metal sheet pile with a diameter of 82 cm. The advantages of this option include, first of all, that you need to order less " windows" near the Volga railway during construction. The disadvantage is its high cost.

According to the results of a technical and economic comparison, the cost of building an overpass according to option 1 is 2660.16 thousand rubles in prices of 2001, the cost of building an overpass according to option 2 is 44885 thousand rubles in prices of 2001. The first version of the overpass scheme was accepted for further development, as the most economical.

The project provides for the construction of the overpass in two stages with dimensions G-15.25 m + 1Tx0.75 m each. First of all, an overpass will be built to the right of the existing overpass with a clearance of G-15.25+1Tx0.75, and the existing overpass will be used at this time as a detour. In the second stage, traffic will be switched to the newly built overpass. The existing overpass will be dismantled and a new one will be built in its place, also with a dimension of G-15.25 + 1Tx0.75 m, under the load A14. The construction of overpasses with two separate dimensions will reduce the moments transmitted to the supports due to the uneven distribution of the temporary load on the bridge and facilitate the construction of foundations, which will significantly reduce construction costs. The distance between the axes of the carriageways of the two overpasses will be 17.45 m.

2.2. Design solutions for the reconstruction of the overpass.

2.2.1. Construction of overpass supports.

The extreme supports OK 1, OK 4 of the overpass across the railway are taken to be piled in relation to the TP series 3.503.1-79 with piles with a section of 35x35 cm.

In the direction across the overpass, the extreme support for each direction of movement consists of ten pairs of piles (ten inclined and ten vertical) with a section of 0.35x0.35 cm. Prismatic piles with a section of 35x35 cm are taken according to standard project series 3.500.1-1.93. The pitch of the piles in the direction across the overpass is 1.8 m.

The crossbars and cabinet walls of the supports are designed from monolithic reinforced concrete. Intermediate supports are accepted as rack-mounted in relation to the TP series 3.503.1-95 on a pile grillage of piles with a section of 35x35 cm. In the direction across the overpass for each direction of movement, the support consists of five racks with a section of 80x50 cm.

The load from the superstructures is transferred through the supporting parts to the monolithic reinforced concrete sub-truss platforms.

2.2.2. The design of span structures.

The overpass along the length consists of two extreme span structures with a length of 21.0 m and an average length of 24.0 m. opposite directions movement. The distance between the axes of the carriageway is 17.45 m. The span structures are 24 m and 21 m long, reinforced concrete, beams, from I-beams with prestressed reinforcement for bridges and overpasses for class A14 load. In the transverse direction, consisting of one direction, the movement of ten beams 24.0 m long, 21.0 m long. No. 54086-M and No. 54125-M. The spacing of the beams is 1.75 m. methodological recommendations on the use of structures of temperature-continuous spans” (Ministry of Transport of the Russian Federation, 2003). Expansion joints "Maurer" are arranged above the extreme supports OK1 and OK4, a continuous roadway is arranged above the remaining supports. The design of expansion joints is assigned from the condition of ensuring the calculated temperature displacements. The span structures are supported on the crossbars of the supports through the rubber-metal bearing parts of the ROCHSP with dimensions of 30x40 cm and a height of 9.7 cm.

2.2.3. Bridge canvas.

The pavement of the carriageway is provided from crushed-stone-mastic asphalt concrete ShMA 20 with a thickness of 50 mm with protective layer from cast asphalt concrete 60 mm thick with waterproofing from Technoelastmost C 5 mm thick over a preparatory layer 30-70 mm thick. Barrier fence adopted according to TU 5216-063-01393697-2006 manufactured in Ulyanovsk with a height of 1100 mm. The brand was adopted in accordance with the current regulatory requirements of GOST R 52289-2004 and GOST R 52607-2006 with a holding capacity of 300 kJ. Railing - metal 110 cm high.

Expansion joints are accepted only above the coastal supports of the Maurer type construction.

2.3. Pairing the bridge with the embankment approaches.

Bridge junctions with embankments of semi-buried approaches individual design, from prefabricated reinforced concrete transition slabs 6 m long and 30 cm high. A crushed stone base 100 mm thick is arranged under the transition slabs. The adapter plates are supported at one end on the cabinet wall, and at the other - on prefabricated monolithic reinforced concrete beds.

All elements of supports and mates, covered with soil, must be protected by coating waterproofing. Upon completion of the main types of work on the construction of supports, the concrete surfaces are painted with modern protective compounds.

2.4. Cones.

The overpass is located in a recess, so the cones have a small height above the slope of the recess. The cones are dumped from draining soil with a filtration coefficient of at least 2 m/day. To prevent settlement during operation, the soil of the cone and backfill must have a compaction coefficient of at least 0.98 m. The slopes of the cones are reinforced with concrete slabs of grade P-1 with a section of 49x49x10 cm over a layer of crushed stone 10 cm thick. A monolithic concrete stop with a section of 40x50 cm is arranged along the bottom of the cones. To organize surface drainage at the ends of the overpass, spillways are arranged on the sides and telescopic trays along the slopes of the embankment, ending with dampers at the sole. Prefabricated elements of drainage structures are adopted according to the standard design series 3.503.1-66. Given the low height of the embankment, stairways at the beginning and end of the overpass are not arranged.

2.5. Organization of work on the construction of the overpass.

The organization of the construction of an overpass across the railway is presented in a separate volume.

2.6. Introduction of new technologies, techniques, structures and materials

The design documentation provides for the use of new priority technologies and materials: 1. Waterproofing roll material "Technoelastmost"C according to TU 5774-004-00287852-00, used for waterproofing span structures.

Distinctive properties this material are high strength, one of the highest durability of all manufactured domestic industry waterproofing materials, the possibility of its laying at low temperatures air (up to - 15°C) without a greenhouse device.

2. The use of expansion joints "Maurer". Expansion joints of this design have proven to be reliable, waterproof, resistant to dynamic loads, durable and easy to operate.

June 2nd, 2013

About what geometric figures have to issue to motorists Southern District Moscow due to the lack of several vital overpasses, and what is planned, I recently . Now let's deal with plans for overpasses through the railway in Moscow and the region. By tradition, also cards and schemes.

Problem
Railway tracks are the arteries of the Russian economy. Unfortunately, they cut other arteries - roads, creating overruns for public and private transport. And there are very few crossings and especially overpasses through railways. But even if there is a railway crossing, it is often impossible to use it. because most time it is covered. And the crossing time is either unpredictable or predictably long.

If you are a motorist or a member of the motorist's family, you probably lost time in such traffic jams.

A characteristic picture before the move is a crowd with a detour along the side of the road. Moving creates problems not only on highways, but in cities.

The reason for this disgrace is trivial. Schedule of trains on all main lines of the Moscow transport hub very dense. And the crossing, for security reasons, is closed in advance before the train passes, and it does not open immediately. Some crossings on the busiest routes - say, Kievsky, Oktyabrsky - are open only 10 hours a day, and mostly at night.

Makes things worse disgusting coverage on crossings. There is a legal conflict here: the authorities are responsible for the condition of the road different levels, but the condition of the coverage within the crossing is the responsibility of Russian Railways. Which, alas, often does not care about the speed and comfort of crossings by cars.

In addition to traffic jams, there is another problem: people are often killed and maimed at railway crossings.




The statistics on the number of collisions of vehicles with trains at crossings is depressing:
- in 2009: 202 car accident, injured 154 human, died 48 ;
- in 2010: 260 accident ( + 29% ), suffered 230 Human ( + 49% ), died 72 (+50% )
- in 2011: 228 accident ( - 12% ), Suffered 191 Human ( - 17% ), died 49 (- 32% )
It seems that in 2011 the situation has improved? Alas: according to the Ministry of Internal Affairs, in 2012 there was a sharp increase in accidents and deaths.
- in 2012: 311 accident ( + 36% ), Suffered 405 Human ( + 212% ), died 89 (+ 82% )
And in 2013 the situation does not improve:
- in 2013 (January-April): 111 car accident, injured 130 man, died 30 .

What is done?
It has long been known that the installation of a barrier and devices blocking crossings (UZP) reduces the risk of an accident at a crossing by 15-20 times. For example, in 2010, only 4 accidents (1.5%) occurred at equipped crossings, and 256 accidents (98.5%) at non-equipped crossings. Compare with the number of equipped and unequipped in 2010: 2352 (21%) are equipped with barriers and SPDs, 8896 (79%) are not equipped. That is, the risk is reduced by 17 times!

Arrangement of 1 crossing with protective barriers and barriers costs only 1-1.5 million rubles. That is, the equipment of 8896 unequipped crossings would cost only 9-13 billion rubles. Compare with the financial performance of Russian Railways: net profit for 2010 is 79 billion rubles, state support for 2011 is 89 billion rubles, revenue in the first quarter of 2011 is 322 billion rubles.

Alas, RZD does not carry out any systematic work on equipping crossings with UZP and barriers. It is equipped with only 20-30 crossings per year: at such a pace of work for another 200 years. I would like to ask the management of Russian Railways: what prevents us from launching a large-scale program for equipping crossings and completing it in 1-2 years? Isn't it enough to save on the lives of citizens?

If concern for the lives of citizens is not enough argument, let's remember the direct losses of Russian Railways as a result of accidents at crossings. For example, on a September night in 2012 in Moscow, at a crossing near the Karacharovo platform, a new test electric train, Lastochka, flew into a MAZ tractor that got stuck on the tracks.

All these are direct economic losses. It would seem that in such cases, Russian Railways should take the initiative to the Government of Moscow to build an overpass here. What do you think has been done instead? Yes Yes, the crossing was completely closed. Now the inhabitants of the "Karacharovsky Triangle" (Probok.net wrote about this most problematic place) instead of two complex connections with " outside world"There was only one left, with an increased load.

By the way, under the pretext of "fighting accidents" (but in reality because of the unwillingness to maintain and equip crossings), Russian Railways closed more than 4 thousand crossings throughout the country in the 90s and 2000s. In 1995, there were 15397 moves in Russia, and in 2010 there were only 11248 (minus 37%). And during this time only 211 overpasses were built across the railway tracks. That is, for 1 crossing removed after the opening of the bridge replacing it, there are 19 crossings removed at the request of Russian Railways. Has the accident rate decreased? Of course not. Against: the load and accident rate on the remaining ones increased, and so large overruns increased. In 1995 the average distance between crossings was 5 km, in 2010 it was 8 km! in Siberia and Far East this distance is 20–30 km or more.

What is being done?
It is clear that by mass installation of barriers and SPDs (if Russian Railways does come down to the lives of citizens), we can increase security, but not throughput in critical places. The cardinal problem can be solved only by the construction of overpasses across the railway tracks!

I wonder how many overpasses across the railway are being built or will be built in the Moscow agglomeration in the coming years? Where will they be located, which ones are already being built, in what order? Finally, how much does a "banquet" cost? Perhaps I did not search well, but I did not manage to get an answer to this question right away. With the help of colleagues from Probok.net and the Roads.ru forum, I had to do “archeology”. Here is the result of our research: in Moscow and the region until 2020 it is planned to build 81 overpasses across the railway tracks! Not counting those under construction within the framework of the Central Ring Road, M11 and others toll roads.

Why is this information not in open access and understandable to all form?
The availability of information has always been weak side authorities: even obviously necessary, useful and winning projects are almost classified in our country. I guess in this case the reason is this: overpasses are planned, designed and built by three "legal entities": Moscow, the Russian Federation, the Moscow region. Each subject has its own document for this:
- near Moscow - Targeted investment program 2013-2015
- near the region - the program "Roads of the Moscow region for the period 2012-2015"
- at Russian Federation– Federal target program "Development of the transport system of Russia (2010-2015)"
Each of these documents contains many different construction objects. Separately, no one allocates overpasses through railways. As a result, there is a lot of information, but there is no one to combine it together.

(Speaking in brackets, the only one so far positive example for visualization - the Moscow region, which singled out the construction of overpasses through the railway in a separate program "Free crossing", and both the regional ones themselves and the planned toll crossings on regional roads are displayed there. Of course, this presentation also has something to work with - for example, not all objects being designed and under construction are indicated there, and visibility can be improved. But the very desire to demonstrate what is being done deserves respect).

To "declassify" information, Probok.net decided to make 3 overpass maps:
- by "departmental" affiliation: Moscow / federation / region free / region paid
- by stage: under construction / designed / planned
- in terms of the impact on connectivity: creating a new link where there was none, or improving an existing one (replacing a crossing with a flyover)
All maps have 81 marks with names, which will make it possible to understand where the overpass will be built.
But we didn't stop there! And in the explanation for each label, we tried to add as much information as possible about the terms, amounts, program, title ( official name). As well as links to schemes and projects that we managed to get. By the way, we tried to orient the schemes to the cardinal points to make it easier to overlay on the map.

Of course, there may be inaccuracies in our reports, for sure something will change. However, it can be used.

1. Map of planned and under construction viaducts through the railway by regions:

Sinim (26) - Moscow viaducts on AIP 2013-2015
Green (28) - overpasses near Moscow under the program "Roads of the Moscow Region for the period 2012 - 2015"
Orange (19) - toll overpasses near Moscow. This is the most uncertain part of the objects - for them there is no clear signed document with guaranteed financing and investors.
Red (8) - federal under the Federal Target Program "Development of the transport system of Russia (2010 - 2015)", subprogram "Roads".

2. Map of planned and under construction viaducts through the railway in 3 stages:
(click on the diagram to go to the map)

Of the 81 planned overpasses across railways:
Green (10) - under construction
Orange (32) - under design (or design completed)
Red (39) - pending design

3. Map of planned and under construction overpasses across the railway in terms of their impact on connectivity:(click on the diagram to go to the map)

Of the 81 planned overpasses across railways:
Green (14) - overpasses that create new connections
Gray (64) - overpasses replacing or supplementing existing crossings
Blue (3) - overpasses replacing or supplementing existing intersections at different levels

About toll overpasses in the Moscow region
I have complex relationship to road tolls.

On the one hand, in 20 years the state has so launched road construction and repair, which sometimes gives the impression that it was done on purpose to give roads to private owners.
On the other hand, they are now clearly trying to catch up. So, in the Moscow region until 2020 by 17 railway crossings it is planned to spend about 70 billion rubles from the budgets of different levels. But there are more than 100 problem crossings in the Moscow region! With an average cost of one overpass of about 2 billion rubles, it would take 200 billion rubles to build them all! Given the scope general budget areas for roads (about 45 billion including federal subsidies), a huge amount road problems(under repair, small throughput, road network deficit) - it is clear that the construction of 100 overpasses in the region only for budget money would require 30 years. Therefore, the Moscow region decided to attract private investors.

The first such project - crossing the Paveletskaya railway on the stretch Vzletnaya - Vostryakovo in the Domodedovo region - was undertaken by one of the structures of the NPF "Norilsk Nickel" - CJSC "Regional toll roads". This is sort of a pilot project; if successful, the experience will be replicated. Some details in the Vedomosti article. The relocations are not given to investors forever: after 20-25 years of operation, investors are obliged to return them to the region.

If anyone is interested in reading the concept of toll roads in more detail, there is such a presentation by ZAO Regional Toll Roads.

Projects and schemes
There are not many schemes yet - only 15. Let's number them according to the numbers on the map to make it easier to find.

4. Shcherbinka
Title "Reconstruction of the railway crossing at 34 km of the Kursk direction of the Moscow Railways with construction road overpass at the address: 34 km, PK 5, Kursk direction, Moscow - Podolsk section, Shcherbinka station, Shcherbinka city, st. Anniversary"

12. Khlebnikovo
Title "Overpass across the railway near Khlebnikovo square in the city of Dolgoprudny, Moscow Region"

23. Dolgoprudny
Title "Construction of an overpass across the railway near Novodachnaya Square in the city of Dolgoprudny, Moscow Region"

27. Schelkovskoe highway 31 km
Title "Reconstruction of sections of the A-103 Shchelkovskoye Highway to the intersection with the Moscow Small Ring. Construction of an overpass at 34 km of the A103 Shchelkovskoye Highway to the intersection with the Moscow Small Ring (with entrances to the city of Shchelkovo and Star City), Moscow Region"

28. Entrance to Domodedovo 43 km
Title "Construction of a transport interchange at km 43 of the A-105 highway access road from Moscow to Domodedovo Airport, Moscow Region"

30. A107 in Alabino-Selyatino
Title "Construction of an overpass on highway Moscow small ring through Iksha, Noginsk, Bronnitsy, Golitsino, Istra on km 2 of the section from the Kyiv highway to the Minsk highway, Moscow region"

31. A107 in White Pillars
Title "Construction of an overpass on the Moscow Small Ring Road through Iksha, Noginsk, Bronnitsy, Golitsyno, Istra on 31 km of the section from Ryazanskoye Highway to Kashirskoe highway, Moscow region"

37-38. Moscow City
Titles "Construction of a railway overpass and reconstruction of railway devices and an overpass over the Smolensk direction of the Moscow Railway (taking into account stopping point"CITY")" and "Extension of the Krasnopresnenskaya embankment with a tunnel under the MK MZHD"

42. Southern rocade(Balaklavsky-Kantemirovskaya)
Title "Southern Rocade. Plot from Balaklavsky prospect to st. Kantemirovskaya"

And here is the UNDER the first section:

43. St. Podolsky cadets - st. elevator
Title "Plot road network: st. Elevatornaya - st. Podolsky Cadets- st. Red Lighthouse"

44-45. Brick recesses - Bulatnikovsky - Zagorevsky
Title "Section of the road network: Kirpichnye Vyemki St. - Bulatnikovsky Proyezd - Zagorievsky Proyezd, including overpasses at the intersection with Paveletsky and Kursk directions MZD"

48. Festivalnaya - Taldomskaya
Title " road junction at the intersection with Festivalnaya street." (within the North-Eastern chord)

50. Kotelniki (stage 1)
Title "Construction of an overpass across the railway and Dzerzhinskoe highway in the city of Kotelniki, Moscow Region"

In the near future, this road will come to a junction under construction with the M5 (Novoryazanskoye Highway).

81. Donetsk - Highway (together with the bridge Highway - Caspian)
Title "Bridge in the alignment of Shosseynaya street."

We do not pretend to be absolute completeness and accuracy, especially since the plans are constantly being adjusted.
Therefore, a suggestion to all who are interested: help spread the link to this post, send your materials and comments.
This will help improve and complete the information. Write about the found errors and inaccuracies (please, with links to documents, photos, etc.). Send schemes and maps of overpasses, photos from construction sites and other useful information.
I will try to post the best in the blog and links on the map.

PS. Thanks