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HISTORY OF TECHNOLOGY, TECHNOLOGY, OBJECTS AROUND US
Metropolitan. History of invention and production
Directory / The history of technology, technology, objects around us Metropolitan (from French metropolitain, abbr. from chemin de fer metropolitain - "metropolitan railway"), metro (French metro, English underground, Amer. English subway) - in the traditional sense, a city railway with shuttle buses running along it by trains for the transport of passengers, separated by engineering from any other transport and pedestrian traffic (off-street). In the general case, the subway is any off-street urban passenger transport system with block trains running along it (for example, a city monorail). The movement of trains in the subway is regular, according to the timetable. The metro is characterized by high route speed (up to 80 km/h) and carrying capacity (up to 60 passengers per hour in one direction). Subway lines can be laid underground in tunnels, on the surface and on overpasses (this is especially true for urban monorails). The first underground road appeared in London. Its opening took place on January 10, 1863. The length of the line reached only 6 kilometers, and the volume of traffic per day was only 26000 people. The passenger train was driven by a steam-powered locomotive. The burning of coal produced a lot of smoke and soot. When passing through the tunnel, the doors of the car had to be closed, which was reminded by the announcement: "Tunneling in an open car is deadly." So it was until 1906, when the subway section was electrified.
After the London experience, metro construction was developed in other American and European cities. In 1868, the first line was built in New York, then in Chicago, Boston, in 1896 the subway appeared in Budapest and Glasgow. In Paris, the first metro line began operating in 1900. Attempts to create a subway in Moscow date back to the beginning of the 1902th century. In XNUMX, the Moscow City Duma, in the presence of newspaper reporters, heard a report by engineer Balinsky about the "Construction of an off-street railway in Moscow", in which the author of the project outlined the advantages of a new type of transport - the subway and the profitability of the event for investors in the creation of an "off-street railway". The decision of the thought was brief: "Mr. Balinsky to refuse his harassment." So the engineering idea was buried, which was destined to be realized only under the Soviet regime.
The development of domestic metro construction was initiated by the Moscow Metro, the first lines of which went into operation in 1935. The first lines Kirovsko-Frunzenskaya from the station "Sokolniki" to the station "TsPKiO named after Gorky" and "Arbatskaya" from "Okhotny Ryad" to "Smolenskaya" had a total length of only 11,4 kilometers and 13 stations. Three types of underground lines are being built: deep, shallow and ground, which corresponds to the methods of their laying - closed (tunnel) and open. Each line laying method has its own technology. The construction of the subway in a closed way is carried out in areas with a difficult urban planning situation, when there are dense valuable buildings and large engineering structures on the route of the future line. In free territories in the peripheral developed areas of the city, metro lines are built more often in shallow or open way. An example of the latter is the Filevskaya line in Moscow and the Darnitskaya line in Kyiv. The cost of building a subway in an open way is much lower than in a closed one, which is largely due to the different technology of work. With the open method, pits for tunnels are dug directly from the surface of the earth. When closed, it is initially necessary to go through a vertical excavation to the depth of the future tunnel, that is, to build a mine shaft.
For sinking shafts, special drilling rigs are used. The first fully automated mine drilling rigs began to be produced by the Japanese company "Toe Koge" in the 1970s. The automatic control system of such installations makes it possible to carry out the entire cycle of face drilling without human intervention according to a program prepared in advance and entered into its computer in the form of punched tape. This is similar to the operation on machine tools with numerical control. The computer's memory is large enough to allow you to enter programs with a lot of data into it. The transition from one mode of operation to another is carried out by pressing a button on the control panel of the unit. The shield method is most often used for driving subway tunnels. The use of a tunneling shield, which is a horizontal steel cylinder, along the contour of which jacks are reinforced, makes it possible to avoid settlement of buildings located on the surface when excavating soil from the tunnel. Inside such a shield, a tunnel lining is built, that is, its covering, a permanent support. It is made either from prefabricated cast-iron elements (tubings) used in aquifers, or from reinforced concrete - for dry soils. Lining elements have the form of rings of various diameters: for metro stations - 8,5 meters, for distillation tunnels between stations - 5,5 meters. Sometimes the lining of tunnels is made of monolithic concrete, using special concrete pumps for this. The construction of such a lining, which is rare in practice, is explained by the need for drying for a long time until the concrete is completely hardened. Shield methods are an environmentally friendly way to build a subway. Therefore, the improvement of the equipment used for sinking continues - increasing the reliability of excavator shields, the use of rotary-type units and equipment with sliding formwork, modular panel equipment and automatic controls. Tunnel structures intended for long-term operation are exposed to groundwater, which can cause corrosion of metal structures. Corrosion is also dangerous because it causes stray currents in tunnels during the movement of electric trains, which intensify the process of destruction that has begun. Therefore, metro builders pay serious attention to improving the technology of tunnel construction and improving the waterproofing qualities of lining materials - concrete, etc. Reinforced artificial ventilation also serves to eliminate excessive air humidity in tunnels and at stations. During the construction of stations, the most complex structures of the subway, the largest amount of work is carried out, requiring the participation of many specialists - from installers, electricians to architects, designers. Particularly labor-intensive finishing work, requiring not only the skill of builders, but also the use of a variety of natural and artificial materials, in particular, improving the quality of waterproofing, especially on open-pit lines. For the first time, Moscow metro builders managed to use polymeric materials - the ceiling of the Chekhovskaya station. At domestic subways, modern machines and mechanisms have been developed and are being introduced to carry out repair and maintenance work on the maintenance of track facilities, electromechanical devices, production lines, diagnostic complexes for the repair of rolling stock, etc. power supply, electromechanical installations and escalators. The modern subway is a complex set of technical systems that work smoothly, clearly and quickly. During the day, trains run every 3-5 minutes. During rush hour, the interval in movement can be reduced to a minute. The driver of each train has a schedule in which, to the nearest second, the time of arrival at the station and the time of departure are indicated. The schedule is checked against interval and calendar hours. The interval clock shows whether the previous train is late, and the calendar clock shows whether the given train is on time. The speed of trains is regulated by an automatic system that also controls the actions of the driver. So, at the entrance to the station, braking is automatically activated. The driver is obliged to turn it off by pressing a button and drive the train manually: there are people along the platform, and if necessary, the automation will not react. If you do not press the button, the composition will stop. The metro is ventilated through exhaust shafts. The train in the tunnel acts like a piston, pushing air through the shaft in front and sucking it in from the one it has already passed. However, in some areas with heavy traffic, due to the operation of motors and brakes, the air temperature sometimes rises so much that it is necessary to pump or pump out air additionally. A special system monitors the microclimate in different sections of the line. The data is sent to the central control room, which gives commands to turn on powerful air pumps. This control room is the "think tank" of the subway. She communicates with the services of the underground economy: by radio - with machinists and locomotive crews, by intercom - with those on duty at the stations. Computers make sure that the whole system works smoothly, the intervals in the movement of trains are respected and there are no emergencies.
If the central control room is the "brain" of the subway, then its "circulatory system" is the power supply. For greater reliability, electric current is supplied from two independent substations: if one fails, the other will automatically connect. In addition, batteries are provided for emergency lighting. Over the years that have passed since the launch of the Moscow metro, four main types and several modifications of cars have changed. Now a new model has appeared - a high-speed, comfortable and ultra-modern "Yauza". This world-class model with a magnificent modern design is being prepared for release by the Mytishchi Machine-Building Plant. "Yauza" is the first wagon made of modular structures in the history of Russian metro construction. Its development began in the late 1980s. Leading designers of the project - Yu.G. Busygin, N.I. Kuznetsov, V.M. Obukhov and N.V. Usoltsev. Sergey Viktorovich Bezrukavny, Chief Technologist of Metrovagonmash CJSC, talks about the new train: "The design takes into account all the requirements for modern rolling stock, especially safety requirements. Firstly, the body of the Yauza is steel - and let us not be tempted by any aluminum alloys, this is dangerous! Of course, they save weight, but in case of fire, especially when it cannot be extinguished quickly, nothing remains of the aluminum.Of course, you know about last year's emergency in the Channel Tunnel: a high-speed train caught fire ... Aluminum cars not only "leaked" - they burned down! Since we abandoned aluminum, we had to reduce the weight of the container - the body plus the bogies - in other ways. We made the Yauza body from high-strength stainless steel using precision welding, which saved about 1,2 tons. Aluminum would give 3, but... Now about other aspects of security. The control system is fully automated. An on-board computer is installed in the driver's cab, in which two programs are embedded: one sets the traffic schedule, the other monitors the accuracy of its observance. If at some point the driver exceeded the speed, the second program gives a command for automatic braking ... ...In each car there are temperature and smoke sensors - the computer reacts to their signals and activates the automatic fire extinguishing system. The latter is carried out in two ways: in the equipment compartment and wherever there are no people, with a gas of a special composition, and in the cabin, special flasks spray a water cloud into the air. And no fire extinguishers! ...Another innovation is the on-board alarm system. In old cars, there is a group of technical diagnostics lights on the dashboard: something did not work - the corresponding light comes on, and the driver knows what happened. In Yauza, it’s different: there is only one light bulb that, in case of any malfunction, flashes brightly with red light - for the driver, this signal means that you need to look at the computer display, and there everything is displayed in clear text - where, what and why. The advantages of such a system are obvious." The Yauza body has an unconventional section. It is not rectangular - there is a radius part, which made it possible to more rationally fit the car into a circular tunnel and increase the capacity by 30 people. Aerodynamic tests have shown a drag reduction of 20 percent. The practical speed of the train is 48 kilometers per hour. Now, for example, it barely reaches 41. The running gear of the car is with pneumatic suspension, adapting to instantaneous load values. An important factor is energy savings. In Yauza, a regenerative braking system was used - with the release of "extra" energy in the generator mode of traction motors. The cabin is spacious, the dashboard is ergonomically designed, air conditioning is installed. The lighting in the Yauza cabin is more generous and at the same time softer than in the old cars. A forced ventilation system was used. Underground and above-ground lobbies of the subway have enriched the architecture of many cities around the world. But the Moscow metro has stations that are unique in their architectural and artistic appearance. It is no coincidence that the three best stations of the first lines were taken under state protection as architectural monuments: Krasnye Vorota, Mayakovskaya, Kropotkinskaya. Each station of the Moscow metro has its own individual image, and the totality of the stations has formed a unique architectural ensemble. Marble, granite, metals, ceramics, glass are widely used in the decoration of columns, pylons, stairs.
In Paris, special attention is paid to the architectural expressiveness of metro stations, express metros, synthesis in the design of ground and underground infrastructure. Entrances to ground and underground facilities are clearly marked with the direction of travel of passengers. In order to attract passengers in the Paris metro, works of art are used. So, at the Louvre station, a sculpture of an Egyptian pharaoh from the storerooms of the world-famous museum was exhibited. Japanese architects, when designing the Umeda transfer station in Osaka, introduced a small river inside the building with the help of special hydraulic structures, which creates original water surfaces and cascades on each floor, while lighting effects and green spaces make the interiors of the building more attractive. Author: Musskiy S.A.
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