synonymSubway(One of the types of urban rail transit) generally refers to subway (one of the urban rail transit line systems)
Subway, yesUrban rail transitA kind of line system refers to the rail transit built in the city, which is fast, large volume, and electric traction.Trains run on totally closed lines. Lines located in central urban areas are basically located in underground tunnels. Lines outside central urban areas are generally located on viaducts or on the ground. The English is Metro (Underground, Subway, Tube). Metro covers all kinds of underground and aboveground right of way exclusive, high-density, and high traffic volume in urban areasUrban rail transit systemThe subway system in Taiwan is also called "Rapid Transit".
In addition to underground laying, subway lines can also be laid overhead or on the ground.Therefore, the subway line can achieve exclusive right of way without level crossing.The first subway in the world wasbritainLondonMetropolitan subway, built in 1860[71]。
In 1860LondonThe first 6-kilometer subway between Farringdon Street and Bishop Road in Paddington was constructed by excavation and backfilling.
The whole line was opened to traffic on January 10, 1863, which was the first underground railway system in the world——London Metropolitan Railway(Metropolitan Railway) carried 9.5 million passengers in the first year of operation.As electricity was not yet widely available at that time, this underground railway had to usesteam locomotiveTraction, and because the exhaust gas released by the locomotive was harmful to human health, the designers at that time had a wide open mind, and the tunnel had to be equipped with ventilation slots to connect with the ground at intervals.
In 1866,City of LondonThe tunnel shield drill developed by J. H. Greathead is used to dig the "pipe type" route.The tunnel is deep to avoid conflict with the building foundation or municipal pipeline and affect street traffic.It was originally planned to use cable for operation, but it will be used laterElectric traction。
In 1870, London opened the first drill and dig subway for passenger transport, crossing the Thames River near the Tower of London, but this railway was not successful. After several months of operation, the line was abandoned because the newly opened Tower Bridge of London replaced most of the passenger traffic.The earliest existing drill and dig subway was opened in 1890. It is also located in London, connecting the city center with the southern area.At first, the railway builders planned to use the promotion method similar to the cable car, but finally they used electric locomotives to make it the first electric subway. At the same time, the subway opened in London in the early days was fully electrified in 1906.As far as other cities in Britain are concerned, Liverpool, England, also opened an underground railway across the city center and the Mercy River in 1886. It was the first underground railway in the world to realize electrification in 1903, earlier than the London subway,However, the underground railway has not yet become a city subway in terms of administration and operation management, but still belongs to Merseyside commuter railway of British national railway network.
The scene of the London subway construction
In 1890, the first 4.8 km electric subway began to operate.In 1900, more tube subways were built in London, and the excavated and backfilled lines were electrified.In the first andthe Second World WarDuring this period, the subway station played the role of air defense shelter.Many other cities follow London's example.The Scottish city of Glasgow opened its subway at the end of 1896.
In 1896Austro Hungarian EmpireOfBudapestThe first subway in the European continent was opened, with a total of 5 kilometers and 11 stations, which is still in use today.Due to the use of steel beam flat roof, the position is relatively shallow, saving a lot of money.
1898ParisThe construction of a 10 km subway was started in France in 1900Metro ParisThe construction speed was accelerated due to the improvement of excavation and backfilling method by engineers in Fulgence Bienvenue.The new method is to excavate shafts at intervals along the line, and then excavate tunnels from both sides of the shaft. Brick masonry foundation is used in the tunnel to support the wood formwork close to the road surface.This method of constructing crown has less interference with ground traffic.The original French name of the Paris subway is Chemin de Fer M é tropolitain (French literal translation means "metropolitan railway", which is directly translated from "Metropolitan Railway", and later shortened to "m é tro", so many urban rail systems are called metro.RussiaIt is also reasonable to use the Cyrillic alphabet instead of the metro, which is called Метро.)
1895-1897bostonCompletedU.S.AThe first subway is 2.4km long.Initially usedtramAnd trolley buses, later changed to electric trains.On October 27, 1904, the world's largest subway systemNew YorkThe city is open to traffic.In 1913, in South AmericaMetro Buenos AiresCompleted and opened to traffic.In the 1930s,MoscowA subway system has been established.In 1954,CanadaToronto Metro opened to traffic.
Adopted in Montreal in the 1960sParisThe second subway system was built for the Type A tire truck.AsianJapanTokyo, KyotoOsaka, Nagoya and other places successively built subways in 1927, 1931, 1933 and 1957.
Comrade Shi Xizhi, the designer of the first subway in New China
On July 1, 1965,Beijing Metro Phase I ProjectThis is the first subway line in China.It was completed and put into operation on October 1, 1969. In November 1969, there was a fire (no casualties) due to the defective power supply mode of the line.The line continued to operate on January 15, 1971 after reconstruction.
In 1976,U.S.ASan FranciscoThe first fully automated high-speed subway was built in the Gulf Area.In the same year, withautomatic control systemThe Washington DC subway officially opened.The light aluminum carriage with air conditioning equipment runs more smoothly and rapidly due to the design of rail and carriage support system. The underground station with unified architectural beauty and passenger safety is also a feature of modern trains and subway buildings.
At the beginning of 1990, Shanghai Metro began to build. By 1993, the first line had been opened. By 2017, it had become the largest subway network in the world.
On March 28, 2024, Changchun Rail Transit Line 6 will be put into operation.[73]
On September 11, 2001U.S.ANew YorkOf911 terrorist attacksIn China, although the subway did not become a direct target of terrorists, it collapsedThe World Trade CenterBuilding（WTC）There is a subway station directly below, and the subway station was also damaged due to the collapse of the building, resulting in death.
On July 7, 2005britainLondonAn explosion occurred, killing 52 passengers and injuring more than 700.
On March 29, 2010RussiaMoscowThere have been two subway bombings, and the death toll has risen to 34, which is preliminarily judged as a terrorist attack.
At 17:56 on April 11, 2011BelaruscapitalMinskThe "October" subway station bombing, which killed 12 people and injured about 200 people, was classified as a terrorist event.
Urban rail transit modelIt refers to subway, etcUrban rail transitThe model of the vehicle used.Generally speaking, there is no uniform standard for urban rail transit models around the world, and they are often customized according to the needs of a local subway, such asMetro New YorkSystem A and System B of.stayChinese Mainland，Urban rail transit modelIt is often divided into four types: A, B, C, D and L type.
Type A vehicle
Vehicle length: 21-24m, effective length 22.1m
Vehicle width: 3m
Maximum passenger capacity of each vehicle: 310 persons
2~5 pairs of doors for each train
Type B vehicle
Vehicle length: 19-21m, effective length 19.8m
Vehicle width: 2.8m
Maximum passenger capacity of each vehicle: 240 persons
2~4 pairs of doors for each train
Type C vehicle (light rail)
Vehicle length: 15-19m
Vehicle width: 2.6m
Maximum passenger capacity of each vehicle: 210 persons
4 pairs of doors for each train
Type C vehicle (city)
Vehicle length: 24.5m
Vehicle width: 3.3m
2~3 pairs of doors for each train
Type D vehicle[50]
Vehicle length: 22m
Vehicle width: 3.3m
2~4 pairs of doors for each train
L-type vehicle
Each L-type vehicle belongs toLinear motorTrains, regardless of size, vehicle capacity and number of doors of each vehicle.
Maximum passenger volume (one-way hourly person time)
Over 45000
30000 to 5500
10000 to 30000
More than 10000
8000 to 25000
6000-10000
Road form
Mainly underground
Mainly underground
Underground or overhead
Ground or underground or overhead
Ground or underground
ground
Road use
special-purpose
special-purpose
special-purpose
special-purpose
Isolated or mixed with a small amount
Mainly mixed
Average station distance (m day)
800-1500
800-1200
600-1000
-
600-1000
600-800
Length (m days)
two hundred
two hundred
one hundred and twenty
-
＜100
＜60
height
high
high
high
high
Low (high day)
low
Vehicle width (m days)
3.0-3.2
two point eight
two point six
2.8-3.3
two point six
two point six
Vehicle seating capacity (single car)
three hundred and ten
two hundred and forty
two hundred and twenty
-
two hundred and twenty
two hundred
Maximum axle load (t)
sixteen
fourteen
eleven
15-17
ten
nine
Maximum speed (km/h)
80-160
one hundred
eighty
120-160
seventy
forty
Average running speed (km/h)
34-40
32-40
30-40
≥60
25-35
15-25
Track gauge (mm)
one thousand four hundred and thirty-five
one thousand four hundred and thirty-five
one thousand four hundred and thirty-five
one thousand four hundred and thirty-five
one thousand four hundred and thirty-five
one thousand four hundred and thirty-five
Rated voltage (v)
DC1500V（1200V）
DC1500V（1200/750V）
DC1200V（750V）
DC1500V/AC25kV
DC600V（380V）
DC380V
Power receiving mode
Overhead catenary/third rail
Overhead catenary/third rail
Overhead catenary/third rail
Overhead catenary/third rail
Overhead catenary/third rail
Overhead catenary/overhead catenary+battery
Automatic train protection
yes
yes
yes
yes
Yes/No
nothing
Train operation mode
ATO/driver driving
ATO/driver driving
ATO/driver driving
ATO/driver driving
Driver driving
Driver driving
Driving control technology
ATC
ATC
ATP/ATS
ATC/CTCSLevel 2 train control system+ATC
ATP/ATS
ATS/CTC
Train formation
3-8
3-8
2-5
3-8
2-4
two
Minimum running interval of train
90 seconds
90 seconds
90 seconds
90 seconds
150 seconds
300 seconds
Performance characteristics
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advantage
Save land: Because the urban land in general metropolis is of high value, building the railway underground can save ground space and make the ground land available for other purposes.
reduce the noise: The railway is built underground, which can reduce the ground noise.
Reduce interference: Because the subway route is different from otherTransport system(such as ground roads) overlap and cross, so traffic interference is less, which can save a lot of commuting time.
energy conservation: In the context of global warming, the subway is the best means of mass transportation.Due to the stable running speed of the subway, commute time is saved in large quantities, which makes people happy to ride, and also replaces many energy consumed by driving.
Pollution reduction: General cars use gasoline or oil as energy, while subways use electric energy, without exhaust emissions, and will not pollute the environment.
Other advantages：
Compared with other means of transportation in the city, subway has many advantages in addition to avoiding urban ground congestion and making full use of space.
1. Large traffic volume.The transportation capacity of subway is 7~10 times larger than that of ground bus, which is incomparable to any urban transportation means.
2. On time, the punctuality rate is generally higher than that of bus.
3. The speed is fast. The subway trains are running fast in the underground tunnels. The maximum speed is generally 80 kilometers per hour, which can exceed 100 kilometers or even reach 120 kilometers.
shortcoming
High construction cost: The subway project has a long route and a wide scope of influence. It usually requires demolition, reconstruction, protection and other measures for buildings, structures, pipelines and roads along the line, and the cost outside the project is relatively large.Most subway projects are underground. The cost of underground construction is higher than that of ground construction due to the need to drill and dig underground.
Long lead time: The construction of subway takes a long time in the early stage. Because of the need for planning and government approval, it even needs to be tested.It will take a very long time from the beginning of gestation to the implementation of groundbreaking, ranging from a few years to more than ten years.
Weak resistance to some disasters: Although the subway has a strong resistance to snow and hail, it has a weak resistance to earthquakes, floods, fires and terrorism.Because of the structure of the subway, it is very easy to cause tragedy because of these factors.For this reason, since the emergence of subway, engineers have been continuously studying how to improve the safety of subway.
The specific disadvantages are as follows:
1. Earthquake
It can lead to derailment of moving vehicles, so the subway is designed to stop immediately in case of earthquake.In order to prevent the collapse of subway tunnels, subway structures in earthquake zones must be particularly strong.
2. Flood
As the system in the subway is lower than the horizon, the rainwater on the ground is easy to pour into the facilities in the subway.Therefore, the subway has to plan adequate waterproof and drainage facilities in the design, even if so, the subway station may be flooded.Therefore, in case of rainstorm, the damp proof board at the entrance of the subway station and the waterproof gate on the route must be closed.A well-known example isTaipei Metro There was a flooding event when typhoon Nali hit, andBeijing Metro Line 1It was closed for several hours due to storm water.
3. Fire
In the past, people didn't pay much attention to the fire prevention facilities in the subway station. Once a fire broke out in the station, it would be filled with smoke instantly, which caused a serious disaster. On November 18, 1987, a fire broke out in King's Cross Station of London Metro, England, resulting in 31 deaths.One of the reasons for the fire is the use of a large number of wooden buildings in the London Underground.Therefore, the Japanese subway department stipulates that smoking is prohibited in subway stations to avoid fires.
February 28, 2003, South KoreaDaegu CityThirteen vehicles were burned down, 192 people were killed and 148 injured.In addition to the use of combustible materials for the interior decoration of vehicles, the imperfect smoke exhaust facilities in the station area are also important reasons for such serious casualties in this fire. In addition, a large number of harmful substances such as carbon monoxide are produced when the vehicle materials are burned, resulting in many people being poisoned to death.
major function
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Passenger transport:Most citiesrail transitThe system is used to carry commuter passengers in the city, and in many cases the urban rail transit system will be regarded as the backbone of urban transportation.Generally,Urban rail transitSystem is a method used by many cities to solve the problem of traffic jam.The subway has already taken on the main passenger transport task in many urban traffic. The Moscow subway is one of the busiest subway in the world. 8 million Moscow citizens take the subway once a day on average, and the subway takes 44% of the city's total passenger traffic.Tokyo MetroIts operating mileage and passenger volume are very close to those of Moscow Metro.Metro ParisThe daily passenger traffic volume of has exceeded 10 million person times.The total length of subway operation routes in New York ranks the fifth in the world. The daily passenger traffic volume has reached 20 million person times, accounting for 60% of the traffic volume of various transportation vehicles in the city.MTR Hong KongAlthough the total length is only 43.2km, its daily passenger traffic volume is up to 2.2 million person times, reaching 2.8 million person times at the highest time.
freight transport:U.S.AChicago had an underground railway to carry goods;britainLondon also has an underground railway dedicated to carrying mail.However, the two railways were suspended in 1959 and 2003 respectively.
Civil air defense:In war (e.gthe Second World War）The Mass Transit Railway will also be used as a factory orAir raid shelter。Many countries (such asthe republic of korea）OfMetro systemIn the design, the possibility of war is included in the design, so both the depth of the railway and crowd control are taken into accountnational defenseNeeds.
Avoid cold:In some places, the underground railway is built underground not only to avoid the busy traffic and houses on the ground, but also to prevent the railway system from being damaged by outdoor bad weather. Negative teaching materials includeMoscow MetroThe maintenance cost of ground line 4 and L1 is far higher than that of underground line construction and maintenance due to the extreme cold weather.
a decoration:The urban rail transit system is also used as an indicator to show that the country is superior in economy, society and technology.for exampleFormer Soviet UnionThe subway system ofNorth KoreacapitalPyongyangThe underground railway system of our company also has magnificent decoration.
Components
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Tunnel: Many underground railway tunnels are smaller than those on the main trunk lines;Therefore, generally speaking, the volume of subway trains is relatively small.Sometimes tunnels can even affect the shape design of trains, such as some trains on the London Underground.
power: Most urban rail systems use dynamic distribution (i.emultiple unit train ）, instead of using power centralized.If centralized power is used, push and pull operation is often used.
system: Some advanced systems have been introduced into the automatic train operation system.In London, Paris, Singapore, Guangzhou, Taiwan and Hong Kong, the conductor does not need to control the train.More advanced rail transit system can achieve unmanned operation.For example, the longest automation in the worldLRT(light rapid transient system) systemVancouverSkytrain，All stations and trains of the whole LRT are "unmanned management".Guangzhou Metro APM LineAndShanghai Metro Line 10All areDriverlessThe driver only monitors.
vehicle: The original urban rail system vehicles were made of wood, but later they were made of steel to reduce the risk of fire.Opened in 1953TorontoThe vehicles of the underground railway began to be improved to aluminum, effectively reducing maintenance costs and weight.
Construction method
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Tunnel construction
New York subway construction project adopts open cut backfill method
It is not easy to dig tunnels underground, and it will take a lot of money and time, at least several years to complete.
1. Open cut backfill method: The simplest and direct method is open cut and fill (open cut and backfill).This method is generally to dig large pits on the street first, and then build tunnel structures below. The pavement will be paved again after the tunnel has sufficient bearing capacity.In addition to the road being excavated, other underground structures such as wires, telephone lines, water pipes, etc. need to be reconfigured.The materials for building such tunnels are usually concrete or steel, but older systems also use bricks and iron.
2. Drilling method: Another method is to dig a shaft somewhere on the ground, and then dig a tunnel at the bottom of the shaft.The most common method is to use a drilling machine (submerged shield machine,tbm ）Install the pre prepared components on the tunnel wall while excavating.For places with high density of buildings (such as Hong KongHong Kong Island）The drilling and excavation method is even the only feasible construction method.The advantage of this method is that it has very little impact on streets or other underground facilities, and it can even be built underwater (urban rail systems in London, Seoul and Hong Kong all have many tunnels across rivers or seaports);The design of the tunnel also has more creative space. For example, the station will be higher than the tunnel between stations, which will help the train accelerate when leaving the station and decelerate when entering the station.However, this excavation method is not without its disadvantages. One of them is that it is often necessary to pay attention to the impact of groundwater;In addition, explosives may be required for excavation in some hard rock strata.The underground air supply problem and even the collapse of the tunnel may also cause casualties to workers.In addition, for places with high density of buildings, in addition to avoiding the impact on the building structures around the construction site, it is sometimes necessary to coordinate the utilities where they are located to relocate the underground water and power transmission pipelines so as to make room for the construction of train passages.
Station construction
Open excavation method for subway station
subway stationFoundation pitAccording to the construction method, it can be divided into open excavation method, concealed excavation method and cover excavation method;According to the construction sequence, it can be divided into forward excavation method and reverse excavation method.The following common methods are generally used for construction:
1. Open excavation method: It is applicable to the foundation pit or trench with dense buildings and narrow site conditions. For example, the foundation pit is deep, the groundwater level is high, the stratum basically has no bearing capacity, and the environmental protection requirements are high. It is difficult to ensure the safety and stability of the foundation pit by sloping excavation. When retaining piles and walls can be constructed, the vertical open excavation method shall be used.
2. Excavation sequence of foundation pit cover: It is applicable to foundation pit works with dense buildings, busy ground traffic, narrow site conditions and large scale. For underground works with large excavation scope, high groundwater level, poor formation self stability, and difficult dewatering, or when open excavation is difficult to ensure construction and environmental safety, cover excavation method can be considered.
3. Top down method for foundation pit cover excavation: The top-down cover excavation method is generally applicable to the construction of deep and large foundation pits with dense buildings, busy ground traffic and narrow site conditions, or foundation pits with complex plane shapes.
Power supply mode
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Generally speaking, in order to reduce the construction cost of the tunnel, most subway will choose the third rail power supply mode to reduce the tunnel section, but it is not absolute.The power supply modes of metro are mainly as follows:
Overhead cable
The overhead catenary (also called catenary power supply) supplies powerElectrified railwayOne of the two commonly used power supply network modes is alsoTrolleybusThe only power supply mode.In railway and urban rail transit systems, overhead contact systems have only one electrode of conductors,Electric locomotiveadoptPantographTake the power and return it to the power grid through the metal wheel rail.In the systems using rubber wheels such as trolleys, the overhead contact network has one plus one minus two parallel contact wires (contact wires for short), which pass through twoCollecting poleTake power and form a path.
There are three types of suspension of overhead contact system: simple suspension, chain suspension,Rigid suspension。Both simple suspension and chain suspension areElastic suspension。The corresponding overhead catenary is also calledElastic catenaryandRigid catenary。
1. Simple suspension
Simple suspension has only conductors and no load-bearing lines. Its advantages are simple structure, low pillar height, and light load borne by support points. It is generally used in low clearance situations such as tunnels.Simple suspension is also widely used in urban light rail and trolley bus.Its disadvantage is that the span is small, the suspension point has a hard point, and the conductor will oscillate up and down during operation, so it is not suitable for high-speed railway.
2. Chain suspension
Chain suspension connects conductors and load-bearing lines with suspension cables, which solves the problems of small span and hard spots in simple suspension, so it is widely used in long-distance, high-speed, long-span electrified railways.In urban subway, if chain suspension is used, the running speed is expected to reach more than 120km/h.
3. Rigid suspension
Rigid suspension is a new suspension mode in which hard metal strips (usually copper strips) replace soft conductors.With the development of material science and structural mechanics, rigid suspension makes use of the advantage of large contact area of the third rail power supply, and overcomes the disadvantage that the rail is too heavy to suspend.When the urban rail transit is driven from the underground line to the ground line, it is directly connected with the elastic suspension line seamlessly without replacing the locomotive.At the same time, because the rigid suspension uses a pantograph, the third rail without a collector shoe is easy to fall off, which can achieve higher running speed.However, the disadvantage is that the contact area between the conductor rail and the carbon rod of the pantograph is larger, and the loss of the carbon rod of the pantograph is also larger.
Track power supply
Rail power supply is one of the methods of railway electrification, which is commonly used in the mass transportation system.The third rail adds electrification to the side of the original two track line, and the vehicle uses the collector shoe to obtain power;The current returns to the power plant through the wheels and running rails.In addition to the original wheel support guide and guide rails, the fourth rail power supply adds two additional rails to supply DC positive and negative poles, or three-phase AC power, but it is not as economical as the third rail, so it is uncommon.
The concept of track power supply is thatTrackIn addition, plus live rails.This live rail is usually located between two rails or outside one of them.The collector of the electric train contacts and slides on the track with circuit to transmit power to the train.This kind of collector is called "shoe" in English and translated into "collector shoe" in Chinese.Voltage comparison of track power supply systemCatenaryThe system is small.The catenary can generally provide 25000 volts or morealternating currentHowever, the third rail system can only provide about 1500 voltsDC。
Third and fourth rails:
Generally speaking, only one electrified track is set for the railway with track power supply system.This strip circuit track is called“Third track”。The power obtained from the third rail will generally pass through the trainwheelandTrackReturn to the power plant.
However, some trains with rubber wheels (such asMetro ParisPart of the trains) can not allow the power to be transmitted back to the power plant through the track, so an additional electrified track (i.e. "the fourth track") will be added to the section where these trains are running for the purpose of power transmission back.Interestingly, based on some other advantages of the fourth rail (such as high reliability and reducing the complexity of the signal system), some railway systems using ordinary metal wheel trains will also be equipped with the fourth rail, so that the power supply and travel rails are completely separated.London UndergroundIt is the largest fourth rail railway system.
ItalyMilanThe more special four track system is adopted for Metro Line A.On some sections of the line, a live metal strip is set between the two tracks.The collector shoe of the train is set at the side of the vehicle to match the position of the live metal strip.The third rail on the ground is used for current return.It is worth noting that the catenary power supply system is used in the northern section of the line.
Advantages and disadvantages of track power supply
advantage
The cost of live rail of the device is often lower thanCatenaryLow, because the overhead contact system needs a bracket, but not a circuit rail.In fact, cost is the main reason why many rail power supply systems have not switched to OCS.
The impact of natural disasters on the live rail is less than that on the catenary (except for flooding).
Live rail is more suitable for installation in tunnels with smaller clearance than catenary.
Some passengers think that the catenary is unsightly, compared with the live rail, the visual effect is better.
shortcoming
Exposed outdoor electrified track poses a danger: some people who attempt to cross the track will be electrocuted to death due to the unfortunate step on the electrified track.for exampleTaipei MRT Freshwater LineThat is to say, the power supply section with plane track is equipped with tight wire mesh to prevent people from stepping on it by mistake.
Voltage problem: the voltage of the electrified track cannot be too high, or the current will form an arc between the rails.Because the voltage is not high, a power station should be set up every other short section when building the railway to ensure stable power supply - but this also increases the cost, so it is only suitable for short distance subway or urban rail transportation.In addition, the voltage problem also makes high-speed trains and freight trains not suitable for the track power supply system, so generally trains with low speed and small load (that is, trains usually used for mass transportation) are more suitable for using the track power supply system (but the railway trunk lines in southeast England use track power supply on a large scale).
Speed limit: Since the collector shoe is difficult to grasp the live rail accurately at high speed, the speed limit of the railway with track power supply system cannot be too high.Generally speaking, the upper speed limit of trains with track power supply system is about 130 km (70 miles) per hour.
Current loss: because the electrified track is close to the ground, the current is sometimes lost to the ground.Some electrified tracks will be added with aluminum bars to reduce current loss (because aluminum has better power transmission capacity than steel).However, because the thermal expansion reaction of aluminum is different from that of steel, in order to avoid damaging the electrified rail, there must be aluminum bars on both sides of the electrified rail.
Gap problem:Switch、Level crossingAt the same time, the electrified rail must leave a gap to allow other rails to pass through it.Generally speaking, the trains using track power supply are all EMUs, and the trains almost always have more than one collector shoe, so the gap will not pose any problem.However, in some cases, the train may still be unable to move because all the collector shoes are in the gap and cannot obtain power.At this time, the train needs to be controlled by otherslocomotivePush or connect the emergency cable to the nearest track with circuit to obtain power.As these accidents occur more frequently at busy intersections, they usually lead to serious congestion and delays.Generally, when there is a sharp turn, part of the power loss is caused by the gap between the collector shoe and the third rail.
Mode comparison
Comparison between catenary power supply and third rail power supply
The overhead catenary is greatly limited by the tunnel clearance, and will be under the pressure of civil construction cost in the application of urban subway.Therefore, among the existing urban rail transit, the third rail power supply still occupies a large share.However, some urban rail transit will still use overhead catenary (such asMTR）。In addition, the overhead catenary may cause some people to have visual psychological barriers, which will have a certain negative impact on the landscape.
However, the third rail has the risk of electric shock, and can only be used in closed routes, so it is not suitable for crossing other traffic routesrailway transportationIn the system.On the other hand, the groundHeavy rail systemIn order to meet the needs of high-speed passenger transport and freight heavy load, higher voltage will be used, such as 25 kV power supply system. If track power supply is usedelectric arc，PantographWhen the train runs at high speed, it can also contact with the catenary well,Collector shoeThere is an opportunity to disengage from the power rail.
Safety facilities
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pressure
Due to the high-speed movement of the train in the tunnel, the pressure in the tunnel and vehicle may change dramatically, which may cause uncomfortable feelings for passengers, or affect the service life of the equipment. See the piston effect for the phenomenon of pressure change.If the pressure wave generated by high-speed train movement reaches the tunnel exit, the tunnel exit will be generatedMicro pressure wave noise, disturbing the peace of nearby residents.
Protective door
Metro platform protection door automatically controlled to protect passenger safety.The safety protection door of the subway platform is set along the passenger side of the rail in the platform, including the isolation barrier, sliding door and drive device.The protective door is set along the edge of the subway platform to isolate the train from the waiting hall of the subway platform.
The safety protection door of subway platform is roughly divided into full height closed platform screen door system, full height safety door system and half height (about 1.5m high) safety door system.
The installation of subway platform safety protection door, first, to enhance the safety of subway operation, provide a safe traffic environment for passengers, and prevent passengers from falling or jumping off the track and causing danger;The second is to make the subway run more smoothly and on time.Since the operation of the subway, the incidents of passengers intruding into the subway track (intentionally or unintentionally) have occurred from time to time, and the phenomenon of forced boarding when the doors will be closed has been repeated. These are the main factors causing traffic accidents and subway delays.The installation and use of platform protective door will completely and effectively eliminate the negative effects caused by these factors.Third, the air conditioner at the platform is not easy to run off.
In view of the characteristics of the existing routes and the platforms on the ground routes, in order to enable passengers to breathe fresh outdoor air, half height platform gate systems are mostly used. The door height of such products is about 1.5 meters, which is an open appearance structure. This structure simplifies the interface between the safety door system and civil engineering, does not require special insulation treatment on the platform, and is also simple and convenient to install,It is very suitable for the installation of safety doors on subway lines currently in operation.
In view of the characteristics of new subway platforms, full height safety door systems and novel full height closed large glass platform screen door systems are mostly used.Moreover, as a high-tech product, the full height closed platform screen door system has energy-saving, environmental protection and safety functions, which reduces the exchange of cold and hot air flow between the platform area and the rail transit area, reduces the operating energy consumption of the environmental control system, and thus saves operating costs.
In terms of information transmission of subway safety door system, advanced optical fiber transmission mode is mostly used, and the network topology adopts ring structure.In this way, the status, fault, control network fault, power supply fault, etc. of each PSD unit can be queried on the workstation in the station control room, and the operation status of the station system can also be counted.
Run interval
Due to the traffic congestion in cities, the public generally requires that "it does not require too long waiting time to get on board".For this reason, the running interval of the train is set to be less than 10 minutes.MoscowDuring rush hour, there is a flight every other minute.Generally, trains in two platforms in the station arrive at the same time.But inTokyoPart of the route, the implementation of slow and fast two operation modes at the same time.The fast train will not stop at some smaller stations, and the slow train will stop at each station.
Most of the worldrail transitThe route is from four o'clock in the morning to zero o'clock in the morning.The first bus usually leaves from 4 a.m. to 7 a.m., and the last bus leaves from 10 p.m. to 1 a.m.A few exceptions, the United StatesChicago24 hour operation with New York, USA.
Prohibited articles
On May 14, 2015, the Public Transport Corps of Beijing Public Security Bureau announced《Beijing Rail Transit Prohibited Items Catalogue》In addition to guns, bullets, controlled knives, ammunition, blasting equipment, alcohol and other prohibited articles stipulated by laws and regulations, the Catalogue mainly adds some prohibited articles not stipulated by laws and regulations, but with certain lethality and danger, including lifeProduction supplies are also included in the prohibited scope of rail transit.
These include: kitchen knives, machetes, art knives and other knives, hammers, axes, cones, shovels, shovels, picks and other tools, spears, swords, halberds, and other sharp and blunt tools that can cause personal injuries, cuts, scratches, and chops.At the same time, the ban also applies to the daily necessities such as toilet water, nail polish remover, hair gel, and mousse with signs or tips of flammable, explosive and other dangerous chemicals on their packages, such as more than 2000 ml (including) liquor, more than 5 lighters, 10 boxes or more than 200 matches.
Fire Escape
The fire department said that the subway fire has the characteristics of rapid combustion spread, high temperature, heavy smoke, relatively concentrated personnel, and difficult evacuation and rescue.Therefore, the subway escape should follow the following three principles:
Keep order:Fire experts remind that the subway traffic is large, and once a fire occurs, passengers will easily lose their minds and run around.The ability of passengers to escape from the whole vehicle varies greatly. Once the order is disordered, it will bring great difficulty to the rescue of firefighters.
Keep calm:People in a narrow and closed space are easy to panic once problems occur.At this time, it is very important to calm down and pay attention to observation.For example, in Hangzhou subway station hall and near the platforma burglar alarm, telephone connection andFire hydrantThere is also a special manual alarm in the station hall.In case of fire, the smoke exhaust system will open automatically, and passengers can press the emergency button. People will run wherever the wind blows.
Do not squat down:The crowd in the car is complex, and the escape ability is different.Especially for women, children and the elderly, they will immediately squat down for fear, which will easily lead to stampedes and unnecessary injuries.
Ticket price positioning
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In some areas, the ticket price of the rail transit system is fixed regardless of the time or length of travel.However, in many countries, the ticket price of rail transit is determined according to the distance taken (or divided into different sections according to the mileage).In European countries such as Germany, the ticket price of rail transit adopts a regional system, which demarcates regions by taking a place as the center and radiating outward. In one region (mileage), the ticket price is the same, while in the next region, there is a new ticket price.Many countries have organized transport operation consortia. The rail transit system integrates tickets with other mass transport vehicles. The tickets of the rail transit system can also be used on other transport vehicles (such as buses or regional railways).
Many urban rail transit systems have introduced automatic toll collection systems, which can save a lot of labor and operating costs.Just insert a special ticket orIC cardThe ticket gate of the automatic toll collection system can be automatically released.In Japan, the automatic toll collection device of urban rail transit system also has intelligent functions such as automatically determining whether the balance of tickets is insufficient and determining the number of uses.
In addition, in Germany, Austria and other countries, the operation of rail transit system adopts the "buffet system", that is, to completely abolish ticket checking in the station, but to conduct surprise ticket checking in the train.In this case, a high fine of more than 8 times of the normal fare will be paid if the ticket is evaded (the same system is also applied by other urban transport authorities in these countries).If an overseas tourist evades a ticket for more than a certain number of times, it may even affect the integrity of the tourist's file so that the second visa cannot be successfully handled.
Operation mode
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The operation modes of urban rail transit system are mainly divided into three types.
1. It is operated by the government or an autonomous group, which is called the public sector and is more common in mainland China.
2. It is operated by private enterprises and is private. It is common in Asian countries except China.
3. It is funded by public organizations and operated by private enterprises, which is common in Europe.
Differentiate light rail
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In fact, both light rail and subway can be built underground, on the ground or on overhead roads.As for the rail weight, although the rail weight of subway is generally greater than that of light rail, in order to enhance the stability of the track, reduce the maintenance and repair workload, increase the return section of traction power supply and reduce stray current, both subway and light rail tend to use heavy rail.
First of all, the transport capacity of light rail and subway is different. It is expressed by the maximum one-way passenger volume in peak hours. The maximum one-way passenger volume of subway in peak hours is 30000 to 70000 person times, and the maximum one-way passenger volume of light rail in peak hours is 30000 to 30000 person times.Secondly, the axle load and size of vehicles are different. The axle load of metro vehicles is generally more than 13 tons, while that of light rail vehicles is generally less than 13 tons.The width of metro car is generally 2.8-3 meters, and that of light rail car is generally 2.3-2.6 meters.In addition, subway and light rail vehicles have different requirements for the turning radius of the route. The minimum turning radius of the main line of subway is generally required to be no less than 300 meters, and no less than 250 meters in difficult sections, while the minimum turning radius of the main line of light rail is generally required to be no less than 100 meters, and no less than 50 meters in difficult sections.In addition, there are also differences between metro and light rail in terms of the number of train formations, vehicle seating capacity, maximum operating speed, etc.
Subway in various countries
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China
As of June 30, 2024, a total of 58 cities in the mainland of China have put 11409.79 kilometers of urban rail transit lines into operation, including 194.06 kilometers of new urban rail transit lines in the first half of 2024.In the first half of 2024, there will be no new cities to operate urban rail transit. In the first half of 2024, there will be 10 cities with new lines, new sections or extension lines of urban rail transit, including Wuxi, Changchun, Nanjing, Shaoxing, Qingdao, Hefei, Chengdu, Ningbo, Changsha and Suzhou.In the first half of 2024, 132 new operating stations will be opened, 6 new operating lines will be added, and 4 new sections or extension sections of existing lines will be opened.The newly added 194.06 km urban rail transit operation lines involve three systems, including 146.40 km subway, accounting for 75.44%;30.40 km of urban fast rail, accounting for 15.67%;17.26km tram, accounting for 8.89%[56]。
Summary of China's Metro System (as of September 2024)
This table only includes metro lines, and non metro monorails, trams, urban railways and other lines are not included.
Note 1: Beijing Modern Tram West Suburb Line and Beijing Yizhuang New Town Modern Tram Line T1 belong to modern trams, and Line S1 belongs to maglev, so no record is made.
Note 2: Shanghai Maglev Line and Jinshan Railway do not belong to the metro system, so no records will be made.
Note 3: Kaohsiung Loop Line is a modern tram, so no record will be made.
Note 4: Chongqing Rail Transit Line 2 and Line 3 belong to straddle type monorail, and Jiangtiao Line belongs to suburban railway, so no record is made. The opening time of Chongqing Rail Transit Line 1 is taken as the opening time of the first subway.
Note 5: Wuhan Metro Line 1 is a rail transit constructed in the name of light rail in the subway system to avoid approval. It is also called Wuhan Light Rail Line 1, which belongs to the light rail system approved by the State Council in the early stage. Therefore, the opening time of Wuhan Metro Line 2 is the first subway opening time.
Note 6: Changsha Maglev Line does not belong to the metro system, so no record is made.
Note 7: Dalian Metro Line 3 is a rail transit constructed in the name of light rail in the metro system to avoid approval. It is also called Dalian Express Line 3, which belongs to the light rail system approved by the State Council in the early stage. Therefore, the opening time of Dalian Metro Line 2 is the first subway opening time.
Note 8: Changchun Rail Transit Line 3 and Line 4 belong to light rail. The opening time of Changchun Rail Transit Line 1 is the first subway.
Note 9: Part of the routes of the New Taipei Rapid Transit belong to the management of the Taipei Rapid Transit.
