Низовцев Юрий Михайлович : другие произведения.

Whether the movement of vehicles without traffic jams is possible?

Самиздат: [Регистрация] [Найти] [Рейтинги] [Обсуждения] [Новинки] [Обзоры] [Помощь|Техвопросы]
Ссылки:


 Ваша оценка:
  • Аннотация:
    Abstract The technical solutions provide the non-stop movement practically of any number of vehicles on highways. They are characterized by high throughput and relatively low costs.

  Whether the movement of vehicles without traffic jams is possible?
  
  Despite the high cost of works on movement regulation on highways, the problem of emergence of congestion and jams on them remains not decided that daily practice of the car traffic confirms. Applied methods of regulation of transport streams on city highways in the conditions of the essential increase of the traffic density caused by the considerable increase of number of cars, ceased to be effective.
  The hydrodynamic analogy - Laytkhill- Whitham's model is used in the theory considering movement of transport streams, till this moment. They wrote in the classical work (Lighthill M.J. Whitham G.B. Proc. R. Soc. A 229, 317 (1955)): "... The main hypothesis of the theory consists that in any point of the road flow (cars per hour) are density function (cars on mile) ...". "Byurgers's equation was received on the basis of it and still a number of assumptions and the subsequent generalization. This equation can be considered as Navier-Stokes's scalar one-dimensional equation for incompressible liquid with single density".
  One of representatives of the domestic science about transport streams Afanasyev M. B. also writes: "... movement of a dense transport stream down the street or the road reminds water movement in the channel ... the channel of a certain section can pass quite certain amount of water in unit of time. If we want to pass a bigger amount of water via the channel, we have to increase its cross section. Something similar happens and to the transport stream moving on the channel - the street or the road. The carriageway of a certain width can pass quite certain number of cars and if we want to increase its throughput, we have to broaden the road ... This analogy gave to experts the bases to apply laws of movement of liquid to studying of regularities of transport streams. Such model, however, with certain restrictions allows to perform important researches and to solve a number of practical questions on movement regulation " [1].
  However, the comparison of the results received on this model, with real characteristics of a transport stream showed that this mathematical formula doesn't correspond to anything in real life. The model "liquid on the road" (Laytkhill- Whitham's model) has borders to certain speeds and density. Then "a phase transition" happens, and this model ceases to work. It is necessary to enter two more models - a free stream and moving traffic jams. There is a question: "What parameters define these phase transitions?" For example, for the concept "aggregate state of substance" defining parameter is temperature. For hydrodynamic transitions - stream speed, etc. For transport streams this question remains open [2].
  Scientists of the National research center of Los Alamos (Los Alamos National Lab. - LANL) allocate the following patterns of a transport stream:
  Stage 1. While the road isn't loaded, motorists move at a speed convenient to them, freely passing to the adjacent lanes. Cars at this stage are comparable to a stream of the particles having big freedom in the conveyance.
  Stage 2. As soon as the road becomes overfilled, motorists suddenly lose the most part of freedom of conveyance and are compelled to move already as part of a general transport stream, coordinating with it the speed. Thus they any more have no opportunity freely to change a lane. This stage, similar to water flow, is called as a "synchronized" stream.
  Stage 3. Movement at very large number of cars in a stream gains faltering character (the so-called stop-and-go mode). The transport stream at this stage can be juxtaposed to a stream of the freezing water, cars become on some period as though "pasted" to one place of the road.
  Thus, in the theory of transport streams the last is considered as a liquid or gas stream. Therefore, the concept of "phase transition" in a transport stream is entered by analogy to phase transitions in liquids - transformation of steam into water or water into ice.
  Semenov V. V. explains: "The explanation of the moment and dynamics of change of a phase in a transport stream, by analogy to that as it occurs in the nature, today while isn't present. Differently, phase transitions are high-quality spasmodic changes in speed and density of transport units in a stream. These changes arise locally and extend along stream as wavy. As a result, the stream turns into "jelly". Such condition can keep long enough, hour or two. Such condition arises more often at entries or exits on highways. These phenomena aren't described by any of existing mathematical models but only it is reproduced realistic on imitating models of cellular automatics. Therefore, the gear of phase transitions if they exist in reality, and no simply are beautiful classification, still it isn't clear [2].
  Thus, methods of regulation of transport streams are guided by establishment of a certain order within road situations developing on highways for the purpose of improvement of these situations. And this order is based on hydrodynamic model of a transport stream which as it was noted above, isn't adequate for all road situations and, in particular, doesn't work when a transport stream is being compacted. As the result, enduring traffic jams present on highways of cities.
  Within the approach offered by us the solution of the problem of traffic jams is considered in another plane - in the preservation plane, more precisely, formation and preservation of the mode of the transport stream corresponding to the stage 1 stated above, or the stage of the free stream. A certain type of regulation of transport streams can create such transport situation at which compacting of a transport stream and formation of traffic jams owing to this compacting doesn't arise. That is a blockage of transition of the stage 1 in the stage 2 and 3 is offered. In other words, it is offered to form and retain a traffic mode on a highway at which motorists move at a speed convenient for transition to the adjacent lanes, or all the time to retain such density of a transport stream at which cars are distributed at movement enough far apart and are provided with space for maneuver.
  Certainly, there are also other reasons for formation of traffic jams, for example, the accident as a result of which narrowing of the highway is formed that also leads to the formation of a traffic jam. Nevertheless, and this problem is quite solved within the offered new technique of the regulation of transport streams as the introduction of a reserve-technical (buffer) lane only for entrance or departure of cars allows to use it and for bypass of places of accidents in many cases because the road accidents block all lanes of the route enough seldom.
  Let's return, however, to offered concrete methods of the regulation of transport streams by means of which such transport situation is formed, at which compacting of a transport stream and the formation of traffic jams owing to this compacting doesn't arise.
  It is possible to form and retain a favorable mode of movement on a highway, i.e. the stage of 1 - a free stream - at certain modification on the basis of already long ago known technique "ramp metering" [3], according to which at excessive compacting of movement on a separate site of the road is produced the restriction of the entrance on this site of cars by these or those modes.
  The version of this technique, offered by us, is reduced to the following. On all entries on a highway the traffic lights steered by controllers on the program which allows the entrance only at an average speed of a transport stream, for example, in the range 60-100 km/h. Data on the speed of a transport stream constantly arrive on the controller, for example, from the radars installed here. The controller gives the command on the inclusion of the signal of traffic light forbidding the entrance on a highway at once at an exit of speed of a transport stream out of the bottom limit. The signal of a traffic light switches for allowing the entry of vehicles only at raising by a transport stream of the speed close to the top limit, for example, of 90 km/h (depending on arrangement of a route and time these intervals can be various, for example, 30 - 70 km/h, 40 - 100 km/h). Thus a transport stream doesn't get to the stages 2 (synchronized stream) and 3 (the stop-and-go mode) stated above. As the results emergence of traffic jams depending on compacting of a stream and the corresponding falling of its speed doesn't occur [4].
  The offered approach at the same time allows to reach at the expense of the chosen interval of speeds as it will be shown below, the greatest possible throughput in these conditions on each lane together with opportunity for each car to change lanes that in city conditions is the need because of frequent entries on a highway and frequent exits from it.
  In addition to it the adjacent to entries or exits of a highway the lane is reserved as the buffer: it is used only for entrance and departure of vehicles as well as for bypass of places of accidents or repair. This solution allows to reduce, at least, probability of the formation of traffic jams because of accidents to the minimum limit as well as to avoid traffic jams on a highway at places of the departure of cars withit as cars before departure from a highway relocate beforehand on this buffer lane and don't create hindrances to other cars on operating lanes [4].
  Let's give excerpt from M.B Afanasyev's article "Transport stream" to show obvious inadequacy of traditional hydrodynamic approach for the condensed movement of transport streams.
  "Let's note that according to the traditional theory of transport streams focused on hydrodynamic model, a transport stream can be characterized by three critical parameters: intensity N, average speed V and density D. These parameters are connected by the main equation of a transport stream: N = DV.
  Graphically this equation represents the main diagram of the transport stream. General view of diagram is shown in drawing below.
  It is possible to define characteristics of a transport stream using the equation and the diagram. So, average speed is expressed through a tangent of angle of an inclination of the straight line connecting the beginning of coordinates to a point. Coordinates of this point characterize a certain intensity and density (N/D). Greatest possible under existing conditions intensity of movement as it follows from the chart, is reached at a certain density of a transport stream (point A on the chart) and is called as throughput of a lane or road. It is characteristic that at density of a stream, bigger than in point A intensity of movement decreases. It is explained by that at big traffic density, often there are traffic jams, speed decreases and it leads to reduction of number of the cars passing in unit of time through any section or a site of the road. From the main diagram and the equation of a transport stream follows very important the conclusion for movement regulation: when there is a requirement to pass the greatest possible number of cars on the road, it is necessary to establish by means of signs a certain mode of speed which provides the greatest intensity" [1].
  
  
  
  
  However, the hydrodynamic model is inapplicable for movement of transport streams of high density, therefore, in our opinion, used general concepts, definitions and the equations given above, can't adequately describe and explain all situations in transport streams.
  In this regard it was necessary to enter, in our opinion, more adequate model of movement of a transport stream which we will give below.
  Let's consider process of formation of transport streams on highways without traffic lights (without adjustable intersections) [4].
  The driver, moving with a certain speed on a lane, complies with a safety distance (lsd). Its length depends from the speed of movement and is defined from the following ratio:
  lsd = τd • v + v²/50,
  where τd - the delay time, i.e. time of reaction of the driver for change of a surrounding situation; v - the car speed.
  If the surrounding situation for the driver is stable and doesn't disturb him, then, how shows experiment, τd make about 0.5 sec on the average. This is characteristic at stable movement of cars on the lanes chosen by it considerable time, for example, on long-distance highways with a speed to 100 km/h.
  At the speed drop below the limit (30km/hour), for example, in the case of the increase of the density of a transport stream, cars are approaching, there is some kind of narrowness which increases with the speed reduction. The road situation is becoming more difficult and time of a delay increases. The experience shows that in this case τd increases up to 1 sec.
  At high speeds of movement, beginning from 90-100 km/h, the tension of the driver also increases as the danger increases, and τd again increases up to 1 sec.
  However, time of a delay 0.5 seconds remains at car speeds from 30km/hour to 90-100 km/h only at stable movement of cars, when is absent "mixing" of stream, i.e. without frequent changes by cars of lanes. And this "mixing", as a rule, happens in city conditions in the presence of regularly located frequent entries on a highway and frequent exits from it. The characteristic example of it is "The third transport ring" (TTR) of Moscow. In this case the situation for the driver is difficult and time of a delay makes about 1 second.
  Time of reaction of the driver τd, of course, depends on experience and qualification of the driver, but on the average it is such.
  The indicator v²/50 takes into consideration dispersion of braking systems of cars.
  The braking distance of the car is determined by formula: sb = v²/2a, where a - negative speedup in m/s². On technical requirements for modern vehicles a have to be not less than 5 m/s². The admissible dispersion has an order about 10%. Let's take as an example the worst option - the car in front is adjusted when braking on a = 5.5 m/s², and the car following it is adjusted on a = 4.5 m/s². Then, if one car going with the speed 25 m/s, passes when braking v²/2a = 625/9, another car will pass way v²/2a = 625/11. The difference of these two segments will be as follows:
  Δs = v²/9 - v²/11= (11v² - 9 v²)/99 = 2v²/99 ~ v²/50 (m).
  Or Δs = v²/2a1 - v²/2a2 = v² (а2 - а1) / 2а1∙а2.
  At а1 = 4.5m/sec² and а2 = 5.5m/sec²
  Δs = v² (5.5 - 4.5)/2 • 24.75 = v²/49.5 ≈ v²/50 (m).
  For example, at v = 25m/sec (90km/hour) and τd = 0.5 sec the safety distance lsd = 0.5•25 + 25²/50 = 12.5 + 12.5 = 25m, and at τd = 1 sec lsd = 37.5m.
  Let's enter the concept of the dynamic length of vehicle ldl. The dynamic length is the sum of an average physical length of the car ls and a safety distance lsd:
  ldl = ls + lsd
  On the average the physical length of the car ls makes 5 meters. Thus, the dynamic length ldl is a site of a road cloth which occupies the car taking into account a safety distance lsd.
  The relation of speed of movement of the car to the dynamic length (v/ldl) is the maximum throughput N of a lane.
  For example, five cars move one after another at the speed 90km/hour (25m/sec), the delay time τd makes 1 sec. They occupy 212.5 meters of a lane (5cars х 42.5 m). At specified speed the distance in 212.5 meters will be passed in 8.5 seconds, i.e. in 8.5 seconds will pass all five cars.
  Thus, each car passes ldl (42.5m) for 1.82 sec. In one second the car will pass 23.3 meters, or about 5/9 ldl.
  Within one hour the throughput N of a lane at this speed and delay time for the driver τd = 1 sec will make: 5/9 x 3600sec = 2000 cars per hour.
  At drop of a speed the dynamic length and throughput of lane will change. For example, if cars move with the speed 7.2 km/h (2 m/s) the safety distance lsd makes about 2.1 meters, i.e. at the delay time τd = 1 sec the distance between cars makes slightly more than 2 meters, the dynamic length ldl - about 7 meters, and the throughput N = 2/7 ~ 0.3 cars/sec,i.e.r it was being reduced approximately twice - with 5/9 cars/sec up to 3/10 cars/sec.
  The calculation of the throughput stated above at the speed 90 km/h is given for traffic conditions on city highways where exits of cars with highways or entries on it from numerous city streets are made almost continuously that assumes almost continuous maneuvering of cars for change of lanes by preparation for the departure from a highway or after the entrance on it and the corresponding tension of the driver. The same is characteristic for city highway-platforms with their frequent entries, exits and crossings between storeys.
  As a result, in these cases and in the range of speeds from 30 km/h to 100km/hour time of reaction of the driver for situation change, or time of the delay makes as well as out of this interval, about 1 second, or time of a delay is raised.
  Let's enter also the concept of a density of a transport stream d which is equal to the relation of a physical length of the car to a dynamic length of the car: d = ls/ldl. This expression reflects the extent of filling with a lane by cars (as a percentage) taking into the account as average physical length of cars, so and safety distances between them defined by the speed of movement of the cars substantially that, in our opinion, is more exact than expression of a density of a transport stream through number of cars on unit (kilometer) of length accepted in the theory of transport streams which explicitly doesn't consider the dependence of the distance between cars from the speed of their movement. From expression d = ls/ldl (see the tab. below) comes to light at once the degree of a sparseness of an automobile stream at various speeds of movement at fixed time of a delay for the driver. The ratio of the lane occupied physically with cars and intervals between cars is visible also. For example, at a slow movement in the case congestion car casings borrow up to two thirds of each lane (the road is clogged by cars), and at speeds of cars higher than 100 km/h car casings borrow less the tenth part of a road lane.
  For an illustration we will provide the table. The table is shown the dependence of a dynamic length ldl, a throughput N of a lane and a density of a transport stream d from the speed of movement of the cars V in the range of speeds from 2 m/s (7.2km/hour) to 45 m/s (162km/hour) for city conditions (at τd = 1 sec on highways).
  
   V (m/sec) ldl (m) N (cars/sec) d (%)
   2 (7.2 km/h)
   3 (10.8km/h)
   4 (14.4km/h)
   5 (18.0km/h)
   6 (21.6km/h)
   7 (25.2km/h)
   8 (28.8km/h)
   9 (32.4km/h)
   10 (36.0km/h)
   11 (39.6km/h)
   12 (43.2km/h)
   13 (46.8km/h)
   14 (50.4km/h)
   15 (54.0km/h)
   17 (61.2km/h)
   18 (64.8km/h)
   20 (72.0km/h)
   21 (75.6km/h)
   22 (79.2km/h)
   23 (82.8km/h)
   24 (86.4km/h)
   25 (90.0km/h)
   26 (93.6km/h)
   27 (97.2km/h)
   28 (100.8km/h)
   29 (104.4km/h)
   30 (108.0km/h)
   35 (126.0km/h)
   40 (144.0km/h)
   45 (162.0km/h)
   7.08
   8.18
   9.32
   10.50
   11.72
   12.98
   14.28
   15.60
   17.00
   18.40
   19.90
   21.40
   22.90
   24.50
   27.80
   29.50
   33.00
   34.80
   36.70
   38.60
   40.50
   42.50
   44.50
   46.60
   48.70
   50.80
   53.00
   64.50
   77.00
   90.50 0.28 (1008cars/h)
   0.37 (1332cars/h)
   0.43 (1548cars/h)
   0.48 (1728cars/h)
   0,51 (1836cars/h)
   0.52 (1872cars/h)
   0.56 (2016cars/h)
   0.58 (2118cars/h)
   0.59 (2124cars/h)
   0.60 (2160cars/h)
   0.60 (2160cars/h)
   0.61 (2196cars/h)
   0.61 (2196cars/h)
   0.61 (2196cars/h)
   0.61 (2196cars/h)
   0.61 (2196cars/h)
   0.61 (2196cars/h)
   0.60 (2160cars/h)
   0.60 (2160cars/h)
   0.60 (2160cars/h)
   0.60 (2160cars/h)
   0.59 (2124cars/h)
   00.58 (2088cars/h)
   00.58 (2088cars/h)
   00.57 (2052cars/h)
   00.57 (2052cars/h)
   00.57 (2052cars/h)
   00.54 (1944cars/h)
   00.52 (1872cars/h)
   00.50 (1800cars/h) 70
   61
   54
   49
   43
   39
   35
   32
   29
   27
   25
   23
   22
   20.5
   18
   17
   15
   14
   14
   13
   12
   12
   11
   11
   10
   10
   9.5
   8,0
   6.5
   5.5
  
  t is visible from this table that at speeds of movement of cars in the range from 10 m/s (36km/hour) to 27 m/s (97km/hour) the throughput N has the greatest value in comparison with remained high-speed modes.
  It is visible also from this table that the throughput N changes slightly in the specified range - about 5%.
  The graphically dependence of a throughput N from a speed of movement of a transport stream is shown below. From the schedule it is visible that the throughput increases approximately twice - from one thousand cars per hour on one lane and approximately to two thousand cars per hour at increase in speed from 7 km/h to 30 km/h, - and then the throughput grows slowly up to 2200 thousand cars per hour right up to 45 km/h, this size of the throughput remains up to the speed 72 km/h, and then there is a slow throughput reduction up to 1800 cars per hour at the speed 162 km/h. Thus, the most favorable mode of movement, from the point of view of use of a throughput of lanes, begins with 30 km/h. However, if at the speed 30 km/h 2000 cars per hour pass on a lane only 30 km, the same 2000 cars at the speed 90 km/h pass already three times bigger distance. Therefore, from the point of view of profitability and quickness of movement it is most favorable to choose more a high-speed mode, but thus, without leaving out of the limit in 100 km/h from the point of view of the traffic safety.
  
  
  
  
  
  This table and the schedule, in our opinion, reflect more adequately dynamics of a traffic on its critical parameters, than, for example, the main diagram of a transport stream (it is shown above), used in the theory of a transport stream, based on the hydrodynamic model.
  The approach stated above on the creation and the maintenance of the unceasing movement can be applied both to multilevel highway-platforms, and to the ground highways which don't have intersections (without traffic lights), like "The third transport ring" (TTR) in Moscow.
  On a concrete example of such highway without traffic lights as "The third transport ring" (TTR) we will show possible results of use of a technique of regulation of transport streams offered by us on the basis of "ramp metering" concerning the throughput and concerning the organization of the unceasing movement (without emergence of traffic jams and congestion).
  Usually at the complicated movement on TTR, for example, in rush hours, on it the cars driving on TTR approximately from 30 entrances on one party of TTR start accumulating. A density of transport streams start to grow and the speed of movement falls. In particular, when falling the speed to 7 km/h with the emergence between cars of the distance in 2 meters and with average length of the car 5 meters on three lanes of one party of TTR at its extent - 36 km - are accumulated (36000m x 3lanes): (5+2) m = 15400 cars. If to take a case that each car before departure from TTR has to pass on it a half (18 km) at the speed 7 km/h then for the car journey in these conditions is spent: 18km: 7km/hour ≈ 2.6 hours. Thus, during 2.6 hours on 1/2 TTR will be able to move 15400cars x 1/2 ≈ 7700 cars, i.t. for one hour on one lane will be able to pass (7700cars: 3lanes): 2.6hour ≈ 1000 cars.
  At the regulation of movement on the offered technique on three through lanes of TTR (extent of TTR makes 36 km) with the same average length of the car (5m) and distance between cars 30 - 40 meters (the speed of movement 60 - 90 km/h) on the average are approximately (36000m x 3): 35m ≈ 3000 cars, or it are less, than in already considered case, by 5 times: 15400cars : 3000cars ≈ 5 (number of cars under existing conditions - admittance of cars into TTR from all entrances by portions - fluctuates approximately from 3300 to 2400). At an average speed of 75 km/h to travel the half of TTK (18 km) is need to spend: 18 km : 75 km / h ≈ 0.24 hours, or about 14 minutes. Thus, during 0.24 hours on 1/2 TTR will be able to move 3000cars x 1/2 ≈ 1500 cars, i.e. for one hour on one lane will be able to pass ((1500cars : 3lanes) : 0.24) ≈ 2025 cars.
  These data indicate the major for the introduction of the offered technique the fact: time demanded on journey of identical distance at established free movement on a highway without traffic lights, for example, at the expense of a restriction of the entrance when going beyond of the established speed interval, is 11 times less the time, spent for the journey of the same way at the uncontrollable entrance of cars in rush hours on the highway. Therefore, it will be possible even in rush hours on highways with the unceasing mode of the high-speed movement significantly to reduce the time in a way.
  As for the highway throughput, the provided data show obvious dependence of a throughput from the speed of movement of a transport stream: a throughput increases with the speed growth in this case more than twice.
  Let's look as far as these skilled data coincide with the calculated indicators received for similar cases from the ratios, entered by us.
  According to the offered approach to an estimate of formation of transport streams the throughput N of one lane is calculated on formula:
  N = v/ldl,
  where ldl is the dynamic length of the car.
  It is determined by formula:
  ldl = ls + lsd,
  where ls is the physical length of the car and it on the average makes 5 meters, and lsd is a safety distance from a front bumper up to a rear bumper of the adjacent cars in a stream.
  It is determined by formula: lsd = τd • v + v ²/50,
  where τd - delay time, i.e. time of reaction of the driver for change of a surrounding situation; v - car speed.
  Let's review the first example: at the uncontrollable entrance of cars on TTR occurs the gradual highway saturation by cars and the speed of a stream of cars falls to 7 km/h (congestion), or 2 m/s, and the delay time for drivers makes in the conditions of the complicated movement about 1 sec. In this case the throughput can be calculated as follows:
  N = v/(ls + lsd) = v/(ls + τd • v + v²/50) = 2/(5 + 1 • 2 + 4/50) = 2/(7 + 0.08) = 0.29 (cars/sec) ≈ 1164 (cars per hour).
  In this example with use of the offered technique the average speed of cars on TTR makes 75 km/h, or 21 m/s, and the delay time for drivers in the conditions of frequent maneuvering, as cars almost constantly enter on the highway and move out of it, makes as well as in the first example, about 1 sec, the throughput is calculated as follows:
  N = v/(ls + lsd) = v/(ls + τd • v + v²/50) = 21/(5 + 1.0 • 21 + 441/50) = 21/34.8 ≈ 0.6 (cars/sec) = 2160 (cars in hour).
  It as a whole coincides with the experimental data according to which the lane throughput increases approximately twice - from 1000 cars per hour to 2000 cars per hour.
  The given example shows that the average daily throughput of each operating lane on condition of preservation for cars of space for maneuvering remains near value 2000 cars per hour, and the time of the pass of half of TTR (18 km) also makes at any time of day about 14 minutes. That is, if within a day on TTR average speed makes 75 km/h (rather rarefied movement), congestion and traffic jams, which reason is falling of speed of a transport stream, won't arise.
  However, the traffic jams may be the result of accident on the route. Therefore, we offered for a bypass of places of the accidents to introduce and use reserve-technical, or buffer (last on the right in the direction of the travel) lanes as well as lanes being remained free during the accident or repair. It allows at the preservation of the mode "ramp metering" (a regular suspension of entrance of cars on the highway, or the controlled entrance on a highway) to retain movement by the unceasing.
  The reserve-technical lane, on which the through passage is forbidden, is used also as the buffer at the entrance and departure of cars, i.e. only for the smooth displacement on it (last lane on the right) from a place of the entrance or to drive up to the exit place from a highway. It allows not to be accumulated to cars on lanes at exits and, thereby, not to block the lanes of the high-speed movement.
  Besides the buffer lanes can be used to drive up to places of accidents or repair of the specialized transport as well as in case of need as lanes for rather rare the movement of the public transport.
  Multiple cutting-down of time of journey of cars on a highway without traffic lights - the TTR type - promotes unloading of an adjacent street road network from cars thanks to their accelerated transfer to destinations through this highway with non-stop traffic and the high throughput and, thus, doesn't worsen, and improves journey conditions on this network, and at the expense of the offered organization of movement the part of lanes of a highway can be used both for its needs, and for rather seldom passing public transport.
  If to mean the transformation of the highways which are available in the cities the most part with intersections into the highways without use of traffic lights, i.e. into the highways with the unceasing movement, then it is necessary to install the elevated or underground overpasses for the cars and pedestrians, crossing the highway.
  The solution to the problem of the traffic jams and congestion in megalopolises with a very large accumulation of cars is the elevated multilevel road constructions in the form of highways-platforms with crossings between storeys, i.e. with the levels, connected with each other. Their throughput is several times above than the throughput of highways operating nowadays. Besides, reserve-technical (buffer) lanes are introduced on each storey of this new road construction. It is difficult to arrange the non-stop movement of vehicles without these buffer lanes [5].
  
  
  
  
  Both of these innovations (interstorey crossings and buffer lanes) in total as well as use in case of an unexpected overload of the highway of a known technique of controlled entrance - "ramp metering" [3], provide the non-stop movement practically of any number of cars at any time, irrespective of arising the accidents or making the repair work.
  Highways-platforms can be installed at first on entrances-exits of the large cities in a year - two if to arrange the production of standard sections of highways-platforms from the metal rolling.
  Highways-platforms also can be installed, at radial and ring planning of the city, on its main radiuses, and hereinafter the highways-platforms can be connected in one or several places by rings that creates the uniform high-level network, similar to the subway, only for the cars, doing fast the journey around the city, without jams and congestion, with the free entry into the city and departure from the city [4].
  Separate storeys or a storey of a network of highways- platforms can be given for movement of small-size road trains or electric trains - elevated analog of the subway, thereby, having given opportunity to people without cars quickly and cheap to move, without going down under the ground, on the considerable distances around the city, since the highways-platforms can be installed over all main land and railway lines of the city [4].
  It should be noted also that the closed highway-platform does not allow an exhaust to come to light, at this the air inside the closed highway platform can be cleared by the powerful converters, released by the industry, for a long time. The noise from cars does not go beyond the closed platform. Besides, the roadbed, closed from above and on each side is not subjected to influence of environment and does not wear out almost. Thus, as well as at bridges, the resource of a platform makes more than 100 years.
  The considerable number of inexpensive parking spaces can be provided on highway-platforms, therefore many cars can be all the time inside these constructions.
  As for cost, for example, square meter of the route StrassenHaus Ltd. costs 1600 euro whereas the square meter of the considered highway platform out of metal rolling with the protective coating (lanes can also be covered with steel- fiber-concrete) costs about 150 dollars, i.e. more than ten times cheaper. As a whole, their operation is cheaper also.
  Besides, any country of the world at project introduction in two-three years can already bypass all countries of the world upon movement automation on highways because practically without expenses in closed space of a platform movement without participation of drivers easily be organized whereas it is supposed that personal rapid transport (PRT), expensive and not too efficient, will be introduced massively only through the decades.
  The problem is worth to consider possibilities of the fastest realization of this simple, reliable and efficient form of road constructions taking into account that on the sources published in the press the damage from traffic jams (2010) only in Moscow in a year make averages $1.5 billion, Moscow area - $4 billion in a year, and in the USA - about $80 billion in a year [5].
  Besides, the control system of movement of cars on highways-platforms with use of the reserve-technical (buffer) lanes and opportunities to control (to limit), if necessary, the entrance of cars on the highways-platforms for preservation of the high-speed unceasing movement can be used and on usual (ground) highways in two different modifications - on highways without traffic lights (without intersections) [6] and on highways with traffic lights (with intersections) at the organization of traffic of cars in the latter case as columns (pools) [6]. It will raise their throughput in 1.5 - 2 times.
  Thus, the problem of the movement of the population in megalopolises can be solved rather quickly, simply and without enormous expenses which are now planned in road and transport branch, but hardly will be productive.
  Thesis statement of the material assumes at the corresponding interest more detailed acquaintance with this issue, for example, on the websites of Amazon and www.liters.ru
  
  
  
  List of reference
  1. Afanasyev M. B. Transport stream. 2009.
  www.drivingplus.ru/driving/dorojnoe-dvijenie
  2. Semenov V. V. Paradigm change in the theory of transport streams. IPM of M.V.Keldysh of the Russian Academy of Sciences. M, 2006.
  3. Stephen Parker "Wisconsin Traffic Operations and Safety Laboratory". 2007г. www.topslab.wisc.edu/projects/3-13.
  4. Makarov Y. F., Nizovtsev Y. M. Development of technical solutions for the implementation of the principle of non-stop movement of vehicles on highways (no traffic jams). Russia. Moscow. Bulletin of transport information. 11.2013.
  5. Nizovtsev Y. M., Nizovtsev A. Y. Two-level discharge overpass without traffic jams. Design options and their economic assessment. Russia. Moscow. Bulletin of transport information. 11.2012 - 01.2013.
  6. Nizovtsev Y. M. Comparative analysis of the main options for non-stop traffic on urban highways. Russia. Moscow. Bulletin of transport information. 04.2013.
  
  
  
  
  
  
 Ваша оценка:

Связаться с программистом сайта.

Новые книги авторов СИ, вышедшие из печати:
О.Болдырева "Крадуш. Чужие души" М.Николаев "Вторжение на Землю"

Как попасть в этoт список
Сайт - "Художники" .. || .. Доска об'явлений "Книги"