Geometric layout schemes for street and road networks. Circle or line

More than a hundred years in Russia and around the world there is a struggle linear settlement systems with radial-ring systems. Naturally, this also applied to the layout of Moscow. I am a supporter of linear systems. Participated in competitions. He even won. However, the conviction of the administrative apparatus and decision-making architects in the “genetic” predetermination of the radial-ring structure of Moscow was so great that linearity was systematically rejected.

Linear structures had to be created anew. It was necessary to spend huge amounts of money on the reconstruction of all types of transport, on roads, and on the development of new urban planning concepts. And the radial-ring system grew as if by itself. Ultimately, by the end of the first decade of the 21st century, the “ease” of the second solution led Moscow to a monstrous densification of buildings and a transport collapse. Moscow is the most striking example of a radial-ring city in world practice. The fan of roads, especially on the Kremlin bank, has formed a radial structure for centuries. At the same time, city fortifications turn into ring boulevards, and the intersections of radial roads with them turn into squares. The streets of Zamoskvorechye converged on the bridges flanking the Kremlin, contributing to the spread of the radial layout in this direction as well. Gradually, a balance was formed between the equestrian and pedestrian size of Moscow and its radial-ring functioning. Despite the appearance railways, industrial suburbs and tram transport, most people moved on foot. Back in the twenties of the twentieth century, “going” to visit, to work and to spectacular places was the basis social contacts Muscovites. Even after the Second World War, with the presence of the metro, many “private traders” with large-wheeled carts accumulated at the stations and heavy things were transported on foot over considerable distances - for example, from the Kievsky (Bryansky) station to the Arbat or Nikitsky Gates. At the same time, mushrooms and berries were collected in the Neskuchny Garden; popular beaches were on the Frunzenskaya Embankment in Luzhniki and on the site of the Novoarbatsky Bridge; a state farm was located near the walls of the Novodevichy Convent; Fili and Sokolniki were dacha places. So far, Moscow has been mostly pedestrian.

Fig 1.

The radial-ring system suited everyone. Since the mid-fifties, Moscow began to expand at incredible speed. By the sixties, a ring road had appeared and in just twenty years a gigantic territory, many times larger than the “old” city, was hastily filled with residential areas. The policy of actively attracting migrant workers brought the population of Moscow to eight million. Dozens of construction plants tried to provide this mass with standard housing. However, such powerful quantitative changes had virtually no impact on the urban planning concept of the city's development. The principle of radial-ring growth was “holy” observed. The City Master Plan Institute expanded its rings and chords. Transport theorists (in particular, Professor V. Cherepanov) proved the advantage of the radial-ring scheme. Administrative districts were formed as sectors of the circle, following a “high” policy, since on the one hand they sought to “touch” the Kremlin and collect party contributions from powerful of the world this, and on the other hand, the peripheral regions provided them with connections with the working masses. The result of all this was the general plan of Moscow in the late seventies with a sectoral daisy-shaped structure. According to its authors, the city was supposed to develop completely evenly, filling the entire territory within the Moscow Ring Road. A center (larger than New Arbat). There were supposed to be green “wedges” between the regions. Industry was actively withdrawn. New highways were laid, metro prominences grew. It is interesting to trace the fate of this “work.” By the 90s, that is, by the beginning of the era of capitalism, everything remained the same. Naturally, sector centers could not be created, since their locations were in no way connected with the life of the city, and their sizes did not correspond to any realities. Industry remained in its place (and sometimes expanded), the green “wedges” began to be “overgrown” with housing, the third ring “stuck” in Lefortovo. By the mid-eighties it became clear that the master plan had failed. A short article does not allow for a broad analysis of this phenomenon.

Rice. 2. Master plan for the development of Moscow 1935 (central part). This document legalized the radial-ring system of the city

Here you can find political, economic and even social reasons, however, we will try to limit ourselves to analyzing only the urban planning foundations of this phenomenon. Theoretically, the radial-ring transport scheme has significant advantages over all others. But this is only if it is built ideally, that is, radial and circular routes are equivalent in terms of travel speeds; systems of turns, U-turns and exits are equally convenient; The central zone is a complex transport interchange. Obviously, this can only be accomplished in a historical city through the systematic destruction of its past buildings. This is how it happened in Moscow, since all highways ended in dead ends in the city center.

Only a transition to a linear structure could save the situation. The idea of ​​linear development of Moscow arose during the construction of St. Petersburg, when Russia acquired a “double” capital. The construction of the railway stimulated the growth of the number of settlements along this route. At the beginning of the twentieth century, fantastic ideas appeared to connect these two cities with a linear system consisting of garden cities. After the revolution, constructivists also actively worked in this direction. Linear cities of Milyutin; Ginzburg's de-urban projects; Okhitovich’s wave-like settlement system and, finally, Ladovsky’s great parabola, demonstrating the “energy” release of Moscow towards Leningrad (Fig. 1). All this was aimed, to one degree or another, at creating a new planning structure for the capital. Before the war, several competitions were held for the reconstruction of Moscow. Many have been proposed the most interesting schemes linear development of the city. But the radial-ring version won and the General Plan of 1935 legalized it (Fig. 2). After this, the systematic destruction of the city center began to satisfy transport requirements. Moreover, transport was supposed to be in the future. And then the streets were convenient only for the masses of people and the army going to the parade. While in Moscow there were 20 cars per 1000 inhabitants, the road network of the thirties satisfied everyone. The crisis came in the late nineties. In the sixties (1968), the first post-war competition for the reconstruction of the capital's center was held. Of the fifteen projects, only the MAR-HI project (in the development of which I took an active part) fully addressed the regional planning and, within the framework of this planning, proposed the linear development of the city. Five main directions were proposed - Leningrad, Yaroslavl, Novgorod, Voronezh, Minsk.

Fig. 4. Another option for the development of Moscow, presented by MARGI at the 1968 competition (supervisor Professor I.G. Lezhava). Two highways are visible, bypassing the central part of the city, partly along the railway zones. The direction of the bypass highways is to St. Petersburg.

The directions are formed by powerful double highways, between which satellite cities of two hundred thousand were located. Thus, five linear residential and industrial formations were created, including some urban areas and a number of settlements near Moscow. Among them are Kuntsevo, Khoroshevo-Mnevniki, Timiryazevo Tushino-Khimki-Khovrino, Zelenograd, Podolsk, Chekhov, Serpukhov, New Kuzminki, Kuskovo, Zhukovsky, Perovo, Balashikha, Izmailovo, Kaliningrad, Shchelkovo-Mytishchi, etc. The newly formed residential and industrial areas were separated by newly created or already existing green areas, industrial areas and transport routes (Fig. 3.). Under these conditions, Moscow turned into many independent residential entities with their own production, business, social and cultural centers. Such transformations should have led to a sharp reduction in labor, cultural and social trips in the Moscow agglomeration. The center of Moscow was formed from two urban entities - the “old” city in the Kamer-Kollezhsky Ramparts with the traditional function of management and the “new” city of the South-Western region with a scientific, production and recreational function. It was assumed that in these two “cities” the control centers of Moscow, the Moscow region and Russia would be located. Business center Soviet Union was formed between these centers along the bends of the Moscow River in the direction from northwest to southeast, in the direction of the ring railway. Despite some fantastic nature, the logic of this project was impeccable. He received first prize. However, the radial-ring version came into use, which was legalized in the master plan of the seventies. This was the same “daisy” that was mentioned at the beginning of the article. Since the Daisy Master Plan did not materialize, twenty years later, in the late eighties (1988), a new competition for the reconstruction of the central part of the capital and again the project that I led proposed a linear development option (Fig. 4).

The project received the second prize, and the first - naturally, the radial-ring one. The “linearity” in the project was more modest than in the ’68 proposal. Over the course of 20 years, the areas through which our systems passed were built up. In the new project, the center of Moscow was surrounded by powerful transport highways, forming a “fish” with its outlines. The “fish” concept, according to the authors, was supposed to stop the endless radial-ring growth of Moscow. The city switched to a linear development system in directions - to the north - Tver, St. Petersburg; to the south - Serpukhov, Rostov-on-Don. Powerful highways bypassing the center were located in the railway zone, where there was a significant reserve of free territories. All “lateral” radial flows “rested” against the “fish” and thus the transport impact on the center was significantly weakened. It is interesting that another twenty years have passed and now, in 2006, powerful automobile routes are planned along these same routes, but within the framework of a developed radial-ring system. With the introduction of capitalism in Russia began new stage development of Moscow.

At the end of the last century, another general plan was formed. He naturally continued to improve the radial-ring structure. Following it, a third transport ring was built in Moscow. Construction of the fourth has begun. A new ring road with giant interchanges was built. Many streets were covered with underground and overground passages. The traffic lights have disappeared. But the flow of cars has increased. All vacant urban areas, including factories, are densely built up with housing. Suburban areas are covered with villas, offices and giant shops are built. All this causes huge morning and evening traffic jams, accidents, and sinkholes. In the near future, outbound routes will begin to be duplicated. But any Moscow road has two ends and its second end (unlike the linear system) ends at the Kremlin. Now in the center, cars are parked in three rows, leaving a narrow lane for passage, and motorization is only gaining momentum... Why haven’t linear systems won? There are many reasons. A short article does not allow for a broad analysis of this phenomenon. Here you can find political and economic, and even social reasons. But the main problem is the underdevelopment of transport and the road network in Russia. For decades in Moscow, the roads were bad and there were few cars. A tram (especially a high-speed one) or a monorail could save it. (Remember that at the beginning of the last century it was the tram that was proposed as the basis for a linear city in Spain proposed by Soria Ymata). But after the war, trams began to disappear and cars rushed into the center. Apparently, Moscow will forever remain a giant radial-ring monster.

In my opinion, radial cities will not come out of the crisis. Even if cars sharply decrease in size, Even if exhaust gases disappear and transport switches to hydrogen fuel. The situation can be improved by multi-level underground systems in the center area, but the most difficult geological conditions, the presence of a metro and an extensive network of huge underground structures are unlikely to allow this. The hope is that in parallel with existing cities Linear settlement systems on an all-Russian scale will appear. The first such Moscow-St. Petersburg system is already beginning to take shape. Next may be a giant linear city from St. Petersburg to Vladivostok. (1)

Rice. 5. Linear cities of the future. Linear system Sibstream.

A new one was proposed linear system settlement along the giant transport corridor connecting the Atlantic Ocean with the Pacific Ocean. The term “transport corridor” has been used in world literature since the 50s. At the Crete Congress, several transport corridors on a European scale were identified. The corridor is a linear system that includes the main modes of transport, energy pipelines, water pipelines and communication links. But the project proposes not just a transport corridor, but a linear settlement system, that is, a city stretched out in a line with all its inherent elements. IN in this case appropriate with living things. Possessing the same vital organs, the hedgehog and the snake (the old city and the linear city) have completely different spatial layouts. Only the victory of the “snake” over the “hedgehog” is predicted. It should also be noted that the proposed linear settlement is not just streets stretched in a line. This is a vast area along the transport corridor. This zone can cover an area of ​​up to five kilometers in each direction. This is a complex organism, including high-speed highways, landing sites for all types of air transport, water transport, high-speed train routes, energy and information channels, as well as the movement of raw materials and cargo, etc. In the transport corridor zones there are gardens, parks, nature reserves, forests, residential areas, towns, villages, industrial, scientific and training centers, supermarkets, offices, etc. In this zone, places of settlements, industry, nature reserves, scientific and educational institutions, centers of trade and culture, etc. should be formed, just as in any master plan of the city. The multi-stage transport system used in this case will have no random intersections, no slippery winter roads, no emergency situations, no traffic jams. Movement along the corridor should be fast and convenient. The train will travel 300 kilometers2 in half an hour (currently during rush hours it can take up to two hours to travel from one end of Moscow to the other). On high speed train, taking into account the stops, a person will be able to cover the distance to Vladivostok in less than a day. From Moscow or St. Petersburg on Sunday you can go to Lake Baikal, and in a couple of hours you can be in the Urals. In addition, this should be not just a transport corridor, but the main city of Russia - the business capital of the country. New Moscow. We called this linear city Sibstream.

Rice. 6. Fragment of the Sibstream system. Transport corridor area

Naturally, historical cities will remain in their places and retain their historical and cultural significance. Moscow will remain the political capital. But all active life may go onto the expressway. The linear highway of the Sibstream (Fig. 5) (new Moscow) will be the main one, but not the only one. It can be crossed by seven transverse highways connecting the waters of the Arctic Ocean with the southern border of Russia. These highways are Murmansk-Novorossiysk, Arkhangelsk-Astrakhan, Vorkuta-Omsk, Norilsk-Krasnoyarsk, Khatanga-Irkutsk, Tiksi-Skovorodovo, Anadyr-Vladivostok. Naturally, we did not invent these intersecting transport corridors. They have already developed and many of them exist. It is also natural that the Sibstream (new Moscow) will branch out and become more complex in many places (for example, a section of the BAM), but its main part will become a ridge by the end of the next century future Russia and will remain so for many more centuries (Fig. 6). So, long live New Moscow, Moscow-Linear. City of the end of the century.

1" The project was created for the international gas congress in Tokyo in 2003 by M.D. Khazanov, I.G. Lezhava, M.B. Shubenkov, R.M. Mulagildin.

2 “The speed of experimental magnetic levitation trains is already reaching 600 km/h.

Lezhava I.G., academician of architecture

The need to classify the network of city streets and roads arose in connection with the need to ensure the movement of all types of urban ground transport within the city. The purpose of the classification is to divide traffic into homogeneous traffic flows in accordance with the functional purpose of the streets.

To increase the capacity of city streets and ensure clear organization of traffic, it is necessary to unify the rolling stock and make it more homogeneous. This makes it possible to distribute transportation along individual highways of the city and according to the degree of impact of rolling stock on the environment (noise, vibration, air pollution), and carry out these transportations taking into account the functional zoning of the city.

Currently, there is only a functional classification of city streets, dividing all city streets according to their purpose, but not according to technical indicators. This is explained by the fact that the street network is included in the master plan of the city with an orientation towards a very distant future (50 - 100 years) and for the development of this network the territory is reserved along the boundaries of which urban development is located. The boundary separating the street from the building area, beyond which buildings should not extend, is called red lines. All street elements that support the movement of pedestrians and vehicles must be located within the red lines.

Placing sidewalks, roadways and other street elements within the allocated areas that ensure the passage of future traffic intensity is more important than standardizing the technical parameters of these streets (Table 1.3).

The accepted classification establishes the minimum number of elements of the transverse profile of the street and their main dimensions. An increase in these sizes is possible with a feasibility study, the basis of which is calculations to assess street capacity, traffic safety and transport losses. Such calculations are mandatory when designing city streets and virtually eliminate the uncertainty associated with the lack of technical classification. The same street category may, depending on the expected intensity

Design speed 100 km/h, number of traffic lanes 4-8, lane width 3.5-3.75 m, longitudinal slopes up to 40%;

traffic have different widths of the main roadway, local driveways, medians and sidewalks. But in any case, the minimum technical equipment of a street is determined by its functional purpose.

The main transportation of passengers and goods in cities is carried out on main streets. It is these streets that determine the type street and road network cities. The number of main streets and their length are determined by the expected level of motorization of the city. For domestic cities, this level is accepted as 180 - 220 cars. per 1000 inhabitants. Smaller numbers refer to the largest and largest cities, larger ones to medium-sized cities and towns. For this level of motorization, the density of the main road network, defined as the ratio of the length of main streets to the area of ​​the district, should be 2.2 - 2.4 km/km 2 of the city territory. This density does not have to be uniform throughout the city. In the central part of the city there is a dense

The number of main streets should be increased to 3.0 3.5 km/km 2 , in peripheral areas with residential buildings - to 2.0 2.5 km/km 2 , in industrial areas - reduced to 1.5 - 2.0 km /km 2, and, in forested areas - up to 0.5 - 1.0 km/km 2.

The density of the local street network in inter-highway areas can reach 2 km/km 2 . It should be taken into account that the placement and storage of personal cars are assumed to be on the roadway of the local street network. The standards for the design of residential areas provide for the placement on the territory of microdistricts of at least 70 % cars of citizens living in this microdistrict, taking into account the estimated level of motorization. Car storage areas in neighborhoods must accommodate at least 25% of passenger cars.

Streets and roads form a network of surface communication routes on the city plan. Based on its outline, it can be attributed, with more or less significant assumptions, to one of the fundamental diagrams of the city’s road network. Such patterns are free, not containing a clear geometric pattern, rectangular, rectangular-diagonal and radial-ring.

Free schemes streets are typical for old southern cities. The entire network consists of narrow, curved streets with a variable width of the roadway, often excluding the movement of cars in two directions (Fig. 1.9, A). Reconstruction of such a street network, as a rule, is associated with the destruction of existing buildings. For modern cities, this scheme is unsuitable and can only be left in protected parts of the city.

Rectangular diagram is very widespread and is characteristic mainly of young cities or old (relatively) ones, but built according to unified plan. Such cities include Leningrad (central part), Krasnodar, Alma-Ata. The advantages of a rectangular scheme are the absence of a clearly defined central core and the possibility of uniform distribution of traffic flows throughout the city (Fig. 1.9, b). The disadvantages of this scheme are a large number of heavily loaded intersections, which complicate the organization of traffic and increase transport losses, and large overruns of cars in directions that do not coincide with the directions of the streets.

The adaptability of the street network to the requirements of modern urban traffic is assessed by the coefficient of non-straightness - the ratio of the actual length of the path between two points to the length of the overhead line. For a rectangular street pattern, this coefficient has the greatest value - 1.4-1.5. This means that in cities with such a street layout, urban transport for the transportation of passengers and goods makes overruns by 40 - 50% With the same traffic volumes, traffic intensity on streets of such cities with all the ensuing consequences (fuel consumption, environmental pollution, increased av

speed, congestion of streets with traffic) is 25 - 40% higher than in cities with radial-ring schemes.

Rectangular-diagonal pattern streets is a development of the rectangular scheme (Fig. 1.9, V). It includes diagonal and chord streets, made through existing buildings in the most congested directions. The non-straightness coefficient for such schemes is 1.2-1.3.

This scheme somewhat improves the transport characteristics of the city's street network, but creates new problems: crossing the city diagonally causes the appearance of complex intersections with five and six merging streets. At low traffic intensity (in total on all streets less than 1,500 vehicles per hour), a roundabout scheme can be used to interchange them; at high traffic levels, traffic interchanges on two and three levels can be used.

Radial-ring scheme street network is typical for the largest and largest cities and contains two fundamentally different types of highways - radial and ring (Fig. 1.9, G).

Radial highways are most often a continuation of highways and serve to deeply introduce traffic flows into the city, to connect the city center with the periphery and individual areas with each other. Ring highways are, first of all, distribution highways that connect radial highways and ensure the transfer of traffic flows from one radial highway to another. They also serve for transport links between individual areas located in the same zone of the city.

An example of such a layout is Moscow. The layout of its street network has evolved historically. The core of this network was the Kremlin. As the city developed as a capital Russian state it was surrounded by city buildings and defensive structures - earthen ramparts and fortress walls. These structures determined the emergence of ring highways. Currently, the number of radial highways has been increased to 20, and ring highways to 3. In the master plan for the development of Moscow, it is planned to increase the number of ring highways to 4, and to improve transport connections between the outer regions of the city, where residential and forested areas of the city are now being created, 4 will be built chord highways belonging to the category of expressways.

The radial-ring scheme of the city's road network does not require the presence of completely closed rings. It is important to ensure the movement of traffic flows from one radial highway to another in the shortest direction - tangential. Individual chords can be located in this direction. It is desirable that they overlap each other and provide communication between all radial highways. The closer to the city center, the greater the need for completely closed rings. On the periphery of the city, the need for transverse transport links is dictated mainly by the volume and direction of freight traffic.

The radial-ring scheme of the street network has the lowest coefficient of non-straightness - 1.05 - 1.1.

Rice. 1.9. Schemes of the city street network:

A- free; b- rectangular; V- rectangular-diagonal; G- radial-ring

In their pure form, all the considered street network schemes are rare in modern large cities. As the city and its transport system develop, the street layout increasingly takes the form of first a radial scheme, and then, after the construction of bypass roads along the city boundaries and streets encircling the city center, a radial-circular one. Within one district, a rectangular street pattern is most often maintained.

Control questions.

What indicator is used to determine the size of a city?

What functional zones are distinguished on the territory of modern cities? What are the boundaries of these zones?

What schemes exist for connecting the city with external roads?

4. How does the layout of the city’s road network affect the load and capacity of the streets?

5. On what basis is the modern classification of the city’s road network based? In determining which street parameters is the estimated traffic speed used?

Lecture 3 (4 hours)

1. Schemes for constructing a city road network

2. Requirements for UDS, characteristics of UDS

3. #G0Classification of city streets and roads

4. Basic technical parameters of roads and intersections

Literature:

1. Klinkovshtein, G. I. Organization of road traffic [Text]: textbook. for universities / G.I. Glinkovshtein, M.B. Afanasiev. – Moscow: Transport, 2001 – 247 p.

2. Lanzberg, Yu.S. Guide to the design of city streets and roads [Electronic resource]. / Yu.S. Lanzberg, Yu.A. Stavnichy. – Moscow: Stroyizdat, 1980. – Access mode: http://nashaucheba.ru/v34383/lanzberg_y.s.,_stavnichiy_yu.a._ed._guide_on_design_city_streets_and_roads. - Cap. from the screen.

3. SP 42.13330.2011. Urban planning. Planning and development of urban and rural settlements. Updated edition of SNiP 2.07.01-89* [Electronic resource]. – Access mode: http://docs.cntd.ru/document/1200084712. - Cap. from the screen.

Schemes for constructing urban road networks.

The planning structure of cities is determined by the nature of the road network (RSN), which serves as the arteries of the city. Streets and roads are transport communications and routes for the movement of people. Water supply, sewerage, energy supply, etc. networks are fixed along them. Thus, the road network forms part of the urban area, limited by red lines and intended for the movement of vehicles and pedestrians, the laying of various networks of engineering equipment, and the placement of green spaces.

Geometric schemes for constructing road transport systems have a significant impact on the main indicators traffic, the possibilities of organizing passenger services and the complexity of traffic management tasks.

The following geometric schemes of UDS are known: radial, radial-ring, rectangular, rectangular-diagonal and mixed (Fig. 1).

Figure 1 – Street network planning systems a-radial; b – radial-ring; c – fan;

g – rectangular; d – rectangular-diagonal; e – diagonal; g – free;

h – diagram of A.H. Zilbertal

Radial the system arose naturally from the road junction. It is convenient for connecting the outskirts with the center, but does not create direct connections between the outskirts. Therefore, the radial highway system can only be preserved in small cities. As a city grows, there is a need to create ring or diagonal connections between its districts, bypassing the center.

Radial-ring The system historically developed from a junction of roads and rings of fortress walls. Being very convenient for connecting the outskirts with the center, it at the same time has the following disadvantages in the conditions of modern large city: concentrates powerful traffic flows in the center, passing transit through it, limits the transport work of radial highways with the throughput of the center; complicates communications between residential areas along chord directions. Therefore, when reconstructing large cities with a radial-ring planning system, there is usually a need to make a number of significant adjustments to these systems - to redevelop the center by dispersing its nodes, creating new highways, rebuilding its mechanical transport networks and, in addition, creating chord highways for communication between districts of the city, bypassing the center (Fig. 2).

Figure 2 - Canberra city center (Australia) has a system of radial and ring streets.

"Fan" The planning system is like half of a radial-ring system. From the cities that arose at river crossings - on a higher, flood-free bank - roads fanned out. As the city grew, semi-circular streets were formed - often along the fortress walls. The fan system is also found in seaside port cities located on the shores of a deep bay, and in seaside resorts, where streets converge to the location of a park, beach and health resorts (Fig. 3).

Figure 3 – “Fan” system, plan of Kostroma

Rectangular diagram characterized by the presence of parallel highways and the absence of a clearly defined center. The distribution of traffic flows becomes more uniform. This pattern is found in a number of “younger” cities in our country, for example, in St. Petersburg, Novosibirsk, Rostov-on-Don, Volgograd, as well as in most cities in the USA. Its disadvantage is the difficulty of transport connections between peripheral points. To correct this shortcoming, diagonal highways are provided that connect the most distant points, and the circuit acquires a rectangular-diagonal structure (Fig. 4).

Figure 4 – Rectangular diagrams: map of Rostov-on-Don, master plan of Manhattan

Mixed(or combined) scheme is a combination of these four types and is essentially the most common. However, it does not have its own clear characteristics. The mixed scheme, as the name implies, is devoid of clear geometric characteristics and represents functionally related, but isolated from each other, residential areas connected highways. This scheme is typical, for example, for resort areas.

Diagonal(or triangular) highway grading system is rare. Despite its indisputable advantages (low coefficient of non-straightness and freeing the city center from excessive transit), it has a major drawback: complex highway junctions that reduce throughput the entire network.

Free the planning system with its curvilinear or broken street routes is characteristic of the plans of many cities of the Middle Ages. The high coefficient of non-straightness makes it inconvenient for large cities. Therefore, when reconstructing them, it is often necessary to break through new direct highways. However, for small cities and, in particular, with difficult terrain, a rationally thought-out open-plan system may be the most acceptable form of building a street network. New open-plan systems with skillful use of terrain features have become widespread in the construction of small cities and towns in England and the USA.

Planning structure of cities

When designing cities, it is important to know the structural features and patterns of formation and development of urban formations.

Structure(lat. structura- structure, arrangement) in urban planning is considered as a certain composition of system elements with a set of stable connections between these elements. The concept of “structure” is interconnected with the concepts of “system” and “planning organization”: structure expresses what is stable, relatively unchanged during various transformations of the system; planning organization - ordering the structural elements of the system.

Complex systems have many structures. Thus, in a city as a system, a distinction is made between planning, functional, compositional, etc.

City planning structure- a schematized model in which the most important and stable elements of urban space are identified: the planning framework and planning areas (zones) of the city, in their interrelation, hierarchical dependence and integrity. The planning frame includes urban and natural frame elements - planning centers and axes (color Fig. IV-1-1).

Planning frame(Italian carcassas- skeleton) is the main structure-forming element of the city. The urbanized components of the city's planning framework are public centers, transport hubs (urban planning centers), main streets and roads (urban planning axes) that form urbanized frame of the city. The natural components of the city's planning framework are green areas and water areas (natural planning centers), linear parks, river valleys, streams, ravines (natural planning axes) that form natural-ecological framework of the city.

Interframe territories located between the planning axes and centers form "textile" - filling the planning frame. The filling is heterogeneous and includes areas of different functional use and urban planning significance. Within the “fabric”, frame elements of the next hierarchical level can be identified.

The planning structure of the city has inertia and resistance to transformation. The layout of the network of main streets of cities may not change for centuries.

When developing master plans for urban development, it is important to rank city streets and squares, parks according to architectural and urban planning significance, and determine the location of representative buildings.

Types of urban planning structures. Various combinations of planning axes and nodes form planning structures of different types.

According to the shape of the frame elements, the most frequently repeated types of urban planning structures are: strip (linear), multi-beam (star-shaped, radial, fan), mesh (regular), ring (radial-ring) (Fig. 4.1.1).

Bandpass (linear) planning structures are formed during the development of cities along large rivers, the sea coast, and transport routes.

Multi-beam (star, radial) planning structures are formed in cities developing at intersection nodes transport communications. Fan planning structures are a type of multi-beam; they are usually formed during the development of cities near bridges over large rivers.

Mesh (regular) planning structures are the result of the purposeful formation of cities based on regular plans.

Ring (radial-ring) planning structures are the result of a relatively uniform territorial growth of cities from the center in different directions.

There are many other forms of drawing frame elements of city planning structures.

Based on the compactness of the layout, the planning structures of cities are divided into compact and dispersed. Compact the planning structure is most typical for small towns. In the process of territorial growth of cities, they “step over” natural obstacles (rivers, ravines, wetlands, etc.); for other reasons, they develop dispersed

Rice. 4.1.1.

As a result, cities with dispersed planning structure (see table 2.1.2).

Complication and transformation of the planning structure of cities. As cities grow and develop, their planning structure becomes more complex and changes. The quantitative growth of the city, the increase in its size is accompanied by an increase in the number of objects public importance- the planning framework of the city is being expanded. The phase of quantitative growth of the urban planning system with a certain periodicity is replaced by a phase of structural reorganization (Fig. 4.1.2).

The life processes of the population are changing, which creates a need for transformation of urban planning formations. In post-industrial

Rice. 4.1.2.

In local cities, the service sector, science and scientific services, education and other types of activities are being developed, which can be implemented within multifunctional urban developments. As a result, there is no need for functional zoning of urban areas.

When developing master plans for urban development, the need arises to create new public centers, lay transport communications, and form landscape and recreational areas, which can transform their planning structure.

To provide sustainable development In cities, it is important to take a differentiated approach to the stable and changeable elements of their planning structures.

The most stable and difficult to change is the planning framework of the city, which includes urbanized and natural elements.

Max: There are many questions, but the main one is this. Moscow has a radial-ring transport scheme, but now the idea is very popular that we need a rectangular system, that the ring system has outlived its usefulness. The construction of metro lines is being discussed, which will not go in a circle, as it is arranged now, but from one area to another, without going into the city center. So the question is: are there any examples of successful solutions for ring systems that are already struggling to cope with passenger flows? And one more question: should we try to make Moscow’s transport system rectangular, not circular? Is it necessary to build so-called chords?
Vuchik: Tangential lines.
Max: Yes.
Vuchik: Various types Circle lines can be very effective - they connect many important radial lines. They reduce the need to travel into and out of the city center to get anywhere. They are also efficient because they do not have the sharp peaks in traffic load that radial lines do. Radial lines go through the city center, so the percentage of labor movements there is very high, they create this peak.
Max: Yeah, everyone goes through the center, or from the center.
Vuchik: But with a ring road, people can get to a place without having to travel through the center. This is especially true for transit. Some people say roundabouts are not practical for transit because they cannot accommodate delays. However, for many cities, roundabouts are not just useful, they are key lines. For example, Seoul in Korea. There metro line number 2 is ring. Or Yamanote - Tokyo Regional Rail Line, one of the busiest lines in the world. It carries about a million passengers a day. Moscow ring I also think the most... people who use the Moscow metro could say that they often use the Circle Line.
The transition of the system from a ring to a rectangular one - I don’t know how this can be done without destroying the city.
Max: So I always ask this question. Well, the very idea of ​​​​building chords is good idea or not so much?
Vuchik: In some cases good..
Max: Because now the main flows of people…. everyone works in the center and moves from residential areas along the ring to the center.
Only some of them travel from one residential area to another because they work or live there. But they also go through the center. I don’t know, this needs to be checked, but I don’t think that the flow is not so large that an entire metro line running from one residential area to another would be in great demand.
Vuchik: So they go along the radial, then through the center and again along the radial?
Max: Yes, that’s how things are now. And it is proposed not to go through the center when moving from one area to another.
Vuchik: It is very difficult to achieve a large volume of transportation on express routes, very difficult. Radial directions usually dominate. Concerning ring roads- it really depends on where they are located. If they are far from the center, we will not receive such large volumes of traffic. But the ring that immediately surrounds the city center is very functional, very attractive and serves to gather and distribute people throughout the city. It reduces the number of non-linear trips and transit, reduces the number of cars scurrying back and forth in search of a less congested path.
Max: A very popular idea in Moscow now is that it is necessary to build many tangential lines, chords. Both in the metro and in the road network - and this, supposedly, will reduce traffic. Does this make sense?
Vuchik: Is it proposed to build peripheral roads that go around the city center, but do not pass through it?
Max: Yes, something like that.
Vuchik: If you build only radial lines, then along them a large number of transport goes straight to the city center, and, as a result, there is one square kilometer where many, many lines converge. And now you no longer know what to do with it. These lines carry the heaviest load. But roundabouts and, in some cases, chords can be very useful, depending on the geography of the city, the behavior patterns of passengers, the location of workplaces, schools, universities, etc.

Vukan Vucik uses the urban planning term “grid”, from Grid plan, which refers to the method of planning ancient cities with streets intersecting at right angles. In the modern Russian-language classification, this type of layout corresponds to the term “rectangular system” of the city.

Thank you very much for the translation