24.6 Working in pairs, practice the questions below and support your opinion by using vivid examples. Make up your own questions
What factors may increase the risk of failures and collapses of R&M ES?
What disasters are most dangerous for Railway and Motorway ES?
What threatens bridges in the case of scours and harsh winter conditions?
What is the aim of the railway safety policy?
Do the railways conduct comprehensive bridge inspections?
What accidents are typical in tunnels?
What equipment can prevent the failure and collapse of R&M ES?
The Tacoma Bridge failed because of its extreme flexibility resulting from aerodynamic instability, didn’t it?
What stopped the construction of the Northern-Muya Tunnel?
24.7 Find the words or phrases that mean natural disasters, causalities, safety and security actions. Using dictionaries, find more words, terminology and word combinations with the same meaning. Exchange them with your partner
Unit 25
UP-TO-DATE BRIDGE AND TUNNEL ENGINEERING IN RUSSIA
25.1 Read the text and try to complement its content with detailed information and interesting facts
At the turn of the third millennium Russia has displayed impressive achievements in bridge and tunnel engineering due to state-of-art construction methods developed by Russian research teams and applied by engineers. Their accumulated experience in design and building methods has resulted into engineering structures with enhanced quality. One of the largest Russian manufacturing corporations TechnoNICOL produces special materials for bridge and tunnel structures for protection against water attack and for heat insulation. Another producing company ITS (Engineering Technological Service) from St Petersburg supplies welding equipment and flux covered wire. Most trusted Russian suppliers of bridge components offer their bearings, seismic protection and monitoring systems, expansion joints, etc. They offer long-term experience and cost effective, secure on site application.
During the celebratory event, when the Big Obukhov Bridge (fig. 5.2h) in St Petersburg was being commissioned, President V. Putin said: “This bridge has proved that the best traditions of our engineering school are alive, they are steadily developing in accordance with the highest standards and using the state-of-art technologies”. The cable-stayed bridge, built in 2004, is the first passage across the Neva River for the “river-sea” class vessels of up to 30 m high. It is the third longest in Russia after the Surgut and Vladivostok Bridges. The bridge carries four expressway lanes, a tramline and a railway line. The Big Obukhov Bridge collected 7,220 votes in the “The most beautiful bridge in Russia” Contest.
The road bridge across the Ob River in Surgut (fig.25.1a) was open to traffic on September 16, 2000. The bridge has become the major transport project in Russia at the end of the XXth century that met the world standards using domestic technologies, building materials, equipment and highly qualified personnel. The Surgut Bridge is one of the longest bridge crossings in Siberia with total length including the access roads of 15 km. The bridge established a record among single tower cable-stayed structures with the central span length of 408 m. It is the longest in the world acoording to the Guinness Book of Records. Its design and construction allowed development of new methods of theoretical calculation, experimental investigation, fabrication methods, and construction of complicated structures in severe climatic conditions. Having built this bridge, Russian engineers proved their ability to meet modern challenges of bridge engineering.
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a - The road bridge across the Ob River in Surgut |
b - The road bridge “Red Dragon” across the Irtysh River in the city of Khanty-Mansyisk |
Figure 25.1. Modern bridges across Siberian Rivers
A cable-stayed structure span the shipping channel, and a continuous beam span the rest of the river in both directions. The architectural merits of the Surgut Bridge are truly captivating with its towers looking like two orange arrows rising up to 149 m in height. Their cross bracings look like a lace net. Practically invisible stay cables connect the tower with the stiffening girder under different angles (from 20° to 70°). The Surgut Bridge also competed for the top position among the most attractive bridges in Russia.
The road bridge “Red Dragon” across the Irtysh River in the city of Khanty-Mansyisk (fig.25.1b) was open in 2004. The river with heavy water craft traffic is 1,100 m wide under the bridge, and features different water levels. The total bridge length is nearly 1,316 m. This unique structure is the key element of the federal road from Perm to Tomsk. The combined system “arch+truss+beam” consists of the central through arch span followed by a continuous steel beam and a trussed girder with top and bottom polygonal chords. The through arch truss has flexible tie-bars, and the adjacent spans are through trusses with wind bracings. The locals call the bridge by the endearing nickname of “A sleeping baby dinosaur”. The main five-span structure is 231 m long, which is the fourth longest in Russia. It claims to be the most attractive bridge in Russia. According to the Internet contest held on the website of the Federal Road Agency of the Ministry of Transport in 2012, it collected 27,500 votes.
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a – the Murom Bridge across the Oka River |
b - The Zhivopysny Bridge in Silvery Woodland across the Moskva River |
Figure 25.2 Modern bridges in European areas of the Russian Federation
The Murom Bridge (fig. 25.2a), which is the fourth cable structure built in Russia, was put into operation on October 1, 2009 by Prime Minister V. Putin who landed his helicopter just on the bridge deck. Speaking to the builders, Putin called their result as an impressive feat. The bridge was an acute need because it was the only way to link the south Russian regions with the city of Nizhny Novgorod. The total length of the bridge crossing is 1.5 km, and it is 15 m wide. The traffic capacity of this bypass reaches 20,000 vehicles per day and in this way, it diverts heavy traffic flows from the centre of Murom to P125.
The cable-stayed structure rests on three concrete towers of 86 m high. The towers are separated from each other by the distance of 231 m. One tower is in the middle of the river, and two towers are on the opposite banks. The bridge spans the River Oka at the height of 30 m. Its cost is nearly $2 billion. There is no other bridge like this one anywhere in Russia. According to the local residents, in windy weather, they actually can hear the bridge’s “singing and speaking” voice produced by hollow towers. The Murom Giant collected 32,700 votes in the “The most beautiful bridge in Russia” Contest, and has become the winner among 16 participating nominees.
The unique cable stayed Zhivopisny Bridge (fig. 25.2b), which crosses the Moskva River at an angle of 16° (almost along the river), carries a bypass of the highway. The bridge, opened in 2007, holds a record of the highest cable-stayed bridges in Europe. It is a combined cable-stayed system with a beam and a trussed arch tower. The fan type arrangement of cable-stays provides the structure with required vertical and horizontal stiffness to torsion. The bridge S-shaped deck exceeds the length of 1.5 km, including a 420 m main section. It runs 30 m across the river Moskva. The bridge is 47 m wide, and its main tower is a 105 m high arch that carries the deck by 78 cable stays. During the evening hours, the bridge looks mysterious when the illumination gradually weakens and turns into dimmed lighting at the upper arch sections creating a magic visual illusion of the unearthly structure vanishing out of sight. This visual sensation deepens due to the unusual shape and lightning of the disk-like observation deck suspended under the top of the arch at a height of 100 m above the ground. The Zhivopisny Bridge is a tourist attraction in Moscow.
The next unique structure is the cable-stayed Russky Bridge (fig.25.3) in Vladivostok built before the Asia-Pacific Economic Cooperation summit in 2012. The bridge spans the Eastern Bosporus Strait, and is the world record for the length of its central span that is 1,104 m long. The total bridge length with its access roads is 3.1 km. The structure is on the world’s top five. It carries two lanes each way, and rests upon the second highest towers of 321-m high with the longest cable stays of 580 m. Two A-shaped towers are of an individual design for each one because standard set of forms was not feasible. They were constructed using self-climbing formwork. The towers are supported by piles of 2 m in diameter, driven at the depth of 77 m. The cable stays incorporate parallel strands made of galvanized wires protected from various adverse impacts. The Russky Bridge is a completely symmetrical structure with a central orthotropic steel box girder. It was the truly momentous event when USK Most set the final 12 m long deck section to its final position at the height of 70 m, where the workers welded it into place making the structure the world’s longest cable stayed bridge. The head of the USK Most Company V.V. Kostylev is an alumnus of Siberian State University of Railway Engineering.
The Russky Bridge was designed to withstand severe climate conditions with ambient temperature swinging from -31°C to +37°C, and, in winter, ice accretion of 70 cm thick. The air speed of storm winds reaches 36 m/s along with water waves of 6 m high.
The Baikal-Amur Trunk Line (BAM) has greatly influenced Russian tunnel engineering. Many alumni of Siberian State University of Railway Engineering took active part in construction of eight new tunnels. Four cape intersecting tunnels with their total length of 5.4 km were built in the western district of the BAM. The Baikal Tunnel with its length of 6.7 km was amongst them. Another three long tunnels were built in the BAM Central District. The length of the Kodarsky tunnel is 2.0 km long, the next is the Dousse-Alinskyi Tunnel, which is 1.8 km in length, and the length of Nagornyi (Upland) Tunnel is 1.3 km.
The Kodarsky single-track railway tunnel is a high-altitude crossing that passes through a seismic country in the Ridge of Kadar with risks of 8.0 magnitude earthquake. During the tunnel driving through the permafrost zones, the warm air entered the underground space and caused thawing in adjacent soil. To keep the permafrost stable, the builders developed their own method of injecting “rough” concrete behind the temporary lining and into the foot of the tunnel. Concrete, acting as heat insulator, stopped thawing and prevented deformation in lining.
Developing underground space and facing unexplainable phenomena, people often tell mysterious stories. For instance, the Kodarsky tunnel is famous for its phantom called “White Shaman” who used to appear unexpectedly and warned the builders of oncoming life-threatening disasters. Once the builders considered his appearance seriously, left the tunnel before the earthquake, and nobody suffered.
The Northern-Muja Tunnel is the longest single-track railway tunnel in Russia. Its length is 15,343 m, and the total length of the tunnel including all galleries is 45 km. The tunnel laying depth ranges from 300 m to 1,800 m. It took the builders nearly 27 years to construct it under the severe continental climate conditions with temperature swinging from +35°С to -56°С. The estimated seismic activity reaches a 9-point earthquake on the Richter scale. The rock massif with tectonic deformation and fracture zones is up to 900 m wide and is followed by the layers of thermal water with temperature ranging from +2°C to +45°C. Huge amounts of this water containing fine-dispersed rock debris material and sand entered the tunnel during its construction at the section of Angarakanskaya Depression. The inrush volume exceeded hundreds of cubic metres per hour under hydrostatic pressure of up to 5 MPa. The completion of this tunnel was a notable engineering feat, celebrated on December 21, 2001.
There is a smaller diameter gallery along the main tunnel path used for transporting drains and extraction of ground waters, for arrangement of engineering equipment and for delivering of technical personnel. It lays parallel to the tunnel, at a distance of 15 m. Three vertical shafts provide tunnel ventilation and ensure the microclimate within the tunnel together with the closed portal gates that give access only to passing trains. Sometimes gigantic icicles can hang from the tunnel crown and endanger the trains. The workers have to remove multi-ton weight ice pieces during technological breaks by travelling in a trolley equipped with a lift platform. The amount of removed ice may reach 5m³ in one break.
While constructing the Northern-Muja Tunnel the researchers, designers and tunnel builders implemented many newly developed engineering achievements: combining of horizontal and vertical dewatering wells at a depth of 300 m; application of chemical grouting in the tunnel face at a great length; putting into practice the pipe barrier method to overcome fracture zones. The engineering equipment within the tunnel is controlled by automation system developed in Computer Engineering and Design Institute at Siberian Branch of Russian Academy of Sciences. Until the tunnel was open to traffic, it took the trains two hours to travel at this railway section using the bypass. The tunnel reduces the travelling time to 20 minutes due to non-stop running. The daily traffic capacity of the Northern-Muja Tunnel is 16 heavy freight trains.
Several original vehicular tunnels appeared in accordance with the plan for the development of southern Russia. The Matsesta tunnel (1.35 km) and the Red Glade Tunnel (2.45 km) were built in the immediate vicinity of Sochi, and two new tunnels between the city of Adler and Red Glade District were built to enhance the road network in this region. The Winter Olympic Games in 2014 stimulated the construction of dozens complicated railway and vehicular tunnels crossing this mountainous district. Such a rapid pace in tunneling and construction is unprecedented in the history of Russian tunnel engineering.
Exercises