Basic noise protection measures. Architectural and planning measures Noise protection measures along the railway

The choice and further specification of the most expedient and rational measures is the ultimate goal in the development of the noise protection section in territorial integrated schemes. The choice of measures is based on a comparative variant assessment and includes a consistent set of decisions on the transformation of the territory, planning and equipping the road network with special noise protection structures, organizing traffic, etc.

The need for noise protection measures is determined based on the noise load of the relevant area and the number of its inhabitants, taking into account the development perspective. The higher the noise load and the greater the number of residents exposed to it, the greater the need for such activities. This approach becomes more differentiated if it takes into account the predominant type of use of the territory and the cost of the building stock located on it.

The choice of noise protection measures in urban planning solutions is carried out in three areas: architectural and planning, architectural and construction, construction and structural. In the general system of noise protection measures for the early stages of design, such as CSE, the role of architectural and planning solutions is increasing, the most effective of which are:

functional zoning of the territory, separation of residential, medical and recreational areas from industrial, utility and storage areas and main transport communications;
formation of a city-wide system of green spaces that contribute to noise protection;
tracing of high-speed and freight roads bypassing residential areas and recreation areas;
differentiation of the road network according to the composition of the traffic flow;
the use of noise-protective properties of the relief when tracing highways;
enlargement of inter-main areas to separate the main building blocks from transport highways and the choice of complex geometric forms of inter-main areas, giving large area acoustic comfort.

Functional zoning of an urban area provides for a clear differentiation of individual functional areas according to their purpose and the interconnection of the noise load created in them with an indicator of the need for noise protection. This ensures maximum removal industrial zones, enterprises servicing all types of transport, transformer, boiler houses from residential, medical and recreational areas, or the issue of choosing separate construction and structural noise protection measures is being considered if it is impossible to provide the necessary sanitary protection zone.

In the formation of urban areas, an important role is played by the system of the road network and the organization of traffic along it. When choosing the layout of the road network, it is advisable to consider the following questions:

an increase in the inter-main space with the intensive use of individual Main passages, provided with special construction and structural noise protection structures;
differentiation of the street and road network according to its purpose, the removal of transit and freight traffic to non-residential areas;
maximum use of natural relief elements.

as soundproofing structures highways ah can be recommended:

noise barrier on the right of way of the highway, or on the same subgrade;
high working level of the embankment of the highway, set on the basis of acoustic considerations;
excavation slopes, the depth of which is determined by acoustic calculation;
retaining walls when the road is located in a recess;
various ceilings erected over the carriageway in the form of galleries or tunnel ceilings;
noise-protective soil shafts;
flyovers.

The noise protection option adopted for implementation, with economic feasibility and ensuring noise reduction to the values regulated by sanitary standards, should include additional requirements: do not contribute to the snow-covering of the subgrade of roads, do not impede snow removal from the roadway, fit well into the landscape and not interfere with inspection of the surrounding landscape by the riders, not to create the danger of traffic accidents, to occupy the smallest possible width of the right-of-way.
The material for the construction of noise protection structures should be selected based on structural and economic considerations. The most widespread are concrete and reinforced concrete. Steel, aluminum, various plastic materials, wood, glass, etc. are also used. The required surface density of structures depends on the required sound insulation /noise penetration through the surface of the structure/, determined by the magnitude of the required reduction in sound level.
As a means of protection environment from traffic noise, noise protection structures themselves become its element, shaping the appearance of the highway and determining its functioning both from a technical and aesthetic point of view.
Noise protection structures are a harmonious, rational proportions element of the surrounding ensemble, which is in “balance” with the external environment, while they must be functional and devoid of architectural excesses.
The reconstruction of roads and the development of projects for protection against traffic noise makes sense only in cases where the excess sanitary norms is at least 3 dBA, since only the excess begins to perceive the human ear.
The effect of the concentration of traffic in a separate corridor can be enhanced by the attractiveness of the main trunk roads and the creation of difficult patterns when driving along a secondary network, by organizing one-way traffic, designing access roads, and locally reducing traffic intensity, and hence noise. This effect can also be achieved by administrative measures to organize traffic, such as the prohibition of through and freight traffic.
Elements of highways that can lead to a change in the speed of movement / intersection of roads / should be located in areas where some increase in the calculated sound levels will not be perceived as undesirable.
It is possible to reduce the noise produced by traffic by influencing the design sound level with operational control by:

coordinated traffic light control; introduction of one-way traffic; construction of bypasses of settlements or individual residential areas;
prohibition of traffic on certain roads or in zones;
movement speed limits.

The shape of the street and road network seems to be quite significant, the noise pollution index of which significantly depends on the linear building density and the size of the inter-main territory. Enlargement of inter-main territories is expedient from 25 to 100 hectares. At the same time, noise levels on the building line will increase by 2-4 dBA. The population living in conditions of discomfort will increase by 7-8%. A further increase in inter-main areas from 100 to 200 hectares leads to a reduction in noise by 2.5 - 3.5%.
The increase in inter-main territories by 2 times from 25 to 50 hectares and further to 100 hectares leads to a decrease capital investments on engineering and technical means of noise protection and annual economic damage per inhabitant by an average of 37%, and when enlarged from 100 to 200 hectares - by 25%.

The choice of reception of placement of buildings in the first row of buildings should be carried out taking into account noise levels on adjacent highways.
Application in planning and development projects of residential areas and microdistricts of architectural and planning solutions that contribute to noise protection / placement of extended residential and utility buildings - screens in the first row of development, the choice of rational methods for placing buildings in the main area, concentrating in quiet areas of buildings with an increased number of storeys of a point type, children preschool institutions schools / will provide acoustic comfort not less than 80
% of the population without the use of engineering and technical means of noise protection.
The choice of types of buildings or block sections should be carried out depending on their placement in the building. The facades of the building that fall into the zone of acoustic discomfort should either have increased sound insulation of window openings, which will contribute to the necessary air exchange in the premises, or such an internal layout in which the living quarters would be turned to a quiet side.
With mixed development, it is advisable to provide for the placement of lower buildings in the first row.
Under the conditions of the historically established planning structure, which is formed around the central part, the main difficulty is the issue of normalizing the acoustic regime in quarterly development areas that are not designed for increased traffic intensity. In such conditions, it is most rational:

creation of ring roads and alternate streets;
arrangement of underground transport communications, partial or complete blocking of highways;
formation of a network of one-way streets; - organization of non-stop movement on the principle of a green wave.

When placing buildings in the conditions of reconstruction, it is necessary, on the basis of the noise map of the quarter, first of all, to determine the zones where it is possible to build new residential buildings without taking noise protection measures.
While maintaining quarterly development, internal redevelopment of residential premises should be envisaged in order to orient residential rooms in the direction “opposite to highways. If it is impossible to provide the required insolation, it is recommended to replace window blocks with windows with increased sound insulation. In the conditions of reconstruction, it may be necessary to develop individual designs of "quiet" windows.
In the general transport structure of the city, the movement of rail transport is characterized by a very noticeable emission activity. It is expedient to design railway lines bypassing the residential area for the passage of transit freight trains without entering the city. Marshalling yards should be located outside cities, and new technical stations and parks of reserve rolling stock, freight stations, yards and container yards- outside the residential area.
Railway lines and stations are recommended to be separated from residential areas of settlements by a protective zone with a width of at least 200 m - for railway lines of categories I and II, at least 100 m - for railway lines of III and IV categories and at least 100 m from station tracks, counting from axis of the extreme railway track, it is necessary to use shielding structures. About 40% of the sanitary protection strip should be protective landscaping.
Territories of sea and river cargo ports, mooring places for ships belonging to citizens, coastal bases and sports clubs for small fleets should be located in suburban areas at distances from the residential area justified by acoustic calculation.
New airports and airfields must be located outside the settlements.
Landscaping is one of the noise protection measures whose effectiveness is most evident in large-scale design.
Green spaces help to reduce the intensity of noise only in those cases when they rise to their full depth with sufficient width above the beam connecting the source and the sound receiver / at least 2-3 m /. With dense landscaping, not only a shielding effect is provided, but additional noise attenuation is also created due to the absorption and reflection of sound inside the green mass. It is advisable to use special ordinary groupings of green spaces, the effect of which is most noticeable.
In the current development, with a small width of landscaping strips, the effect of noise protection is insignificant, however, landscaping is used to create psychological comfort.
It's important to decide common system landscaping at the stage of the territorial CSE of the master plan of the city.
For noise protection purposes, both special alternating "green walls" are used, the effectiveness of which depends mainly on the reflection of sound, and large arrays of green spaces, the effectiveness of which is determined by dispersion and absorption. Multi-row structures achieve the greatest effect with a total width of up to 25 m, green areas - 25 m.
Noise-protective properties are inherent in a special strip of green spaces, consisting of one or two rows of densely planted shrubs and one or two rows of trees with closed crowns with a foliage density of more than 0.8. Such a density can be achieved using a two-tier strip of trees by planting them in a "chessboard" pattern.
When using the territory of sanitary protection zones around industrial and municipal enterprises for the placement of noise protection strips of plantings, the tree-shade method should be used, in which multi-row planting of trees is carried out. The main and accompanying shadow breeds alternate within a row or rows of the main and accompanying breeds. Trees of the main species are planted every 3-4 m in a row at a distance of 3-4 m between rows. The distance between the trees of related species is 2 - 2.5 m. Large shrubs are planted at a distance of 1 - 1.5 m from each other, small ones - 0.5 m. At least 50% of the total number of planted trees should be occupied by the main species, the main properties of which noise protection, smoke and gas resistance and viability in given soil and climatic conditions.
To ensure the maximum efficiency of the strip, it is necessary that the height of mature trees exceed by 2 m or more the conditional line of the direct sound beam between the noise source and the calculated point.
The effectiveness of noise protection measures is the measure by which the need for them is compared with the possible reduction in the burden and reduction in their implementation as a result of the implementation of the measures.
The effectiveness of noise protection measures will be high if, for a given need, a high effect is achieved as a result of carrying out an activity, the cost of which is insignificant.
On the present stage The health of the population should serve as the main system-forming factor in solving both social and economic problems. Being a function of many variables, the health of the population is an integral indicator of the quality of living conditions, including the state of the environment. Since noise pollution is a very active source of discomfort and poses a certain threat due to the steady increase in noise in cities, one should Special attention focus on noise reduction at all stages of design.
The most effective is the solution of noise protection issues at the early stages of design when drawing up territorial integrated schemes for the protection of the environment of cities, as this makes it possible to create favorable conditions at the lowest cost.

Noise barriers

For all settlements that are located close to highways or railway lines, common problem high level noise. In this situation, the owners of the estates are forced to escape from the loud noise with the help of all possible ways. Most often, a high solid fence is still not enough to protect your house and site, for this reason you have to resort to additional measures - to involve special structures and materials. One of the options for creating a noise-protective fence is multilayer panels. Their outer surfaces are represented by metal corrugated boards, and between them there is penoizol or mineral wool slabs. Such a panel simultaneously performs two functions - it reflects and simultaneously absorbs sound, that is, it is a complete noise protection system. IN ready-made the panel is not for sale, it is already assembled on site by representatives of companies that specialize in the construction of fences. The height of the fence is calculated according to a certain scheme: an imaginary line is drawn between the point of the top of the roof ridge, as well as the alleged highest point of the location of the trucks on the road, which must be blocked by a fence. The upper part of the structure must be equipped with a sound baffle.

In the second option, a sound-reflecting stone surface is created. In this case, the base of the stone fence can be made of foam concrete, but the cladding is made of stone - either artificial or natural. The stone is laid unevenly with imitation of slate surfaces. The more small and frequent irregularities a wall has, the more it scatters noise.

The latter option uses a polycarbonate sheet with a thickness of more than eight millimeters. In addition to strength, this material is characterized by a fairly good sound-absorbing property. If you want to create a structure that is more interesting from a decorative point of view, then you can combine polycarbonate with wood.

Noise protection measures

The solution should be sought through a preliminary analysis of the acoustic regime of the main areas, an assessment of the existing and predicted noise characteristics of the highway and the acoustic impact on the buildings of the first development front, as well as the development of noise protection measures that ensure the standard acoustic regime. In real conditions of reconstruction of the main streets it is almost impossible to provide acceptable levels noise on the main territory of a multi-storey residential building, so the main emphasis should be placed on noise protection of residential premises and preservation housing stock. At the same time, noise protection measures can make up a very significant share in the estimate of a city highway reconstruction project.

Acoustic calculation of the territories of the planned highways at the design stage allows minimizing the cost of noise protection measures. Known methods of acoustic calculation of territories according to SNiP II-12-77 "Protection from noise" and "Guidelines for taking into account the requirements for reducing noise levels in urban planning projects" involve grapho-analytical calculation of the noise characteristics of the highway with the construction of noise maps. Modern Computer techologies make it possible to use effective methods for numerical calculation of noise pollution in urban areas. They involve numerical simulation of the noise propagation process, which is a computationally laborious task. An alternative is an approach based on the sampling of the study area and the energy summation of the noise at the study points using GIS. For some selected point on the territory, the summation of energy from discrete point sources is performed. The motorway is a linear source of noise and is represented as a collection of point sources. The calculation of noise energy propagation takes into account the effect of attenuation depending on the distance, as well as the diffraction and reflection of sound, i.e. the influence of sources that are not in the line of sight. This approach potentially leads to some decrease in the accuracy of calculations due to discretization. However, this shortcoming is compensated by the fact that all calculations can be carried out using the GIS itself, and this makes it possible to combine the solution of transport and planning problems with the assessment of the impact of noise pollution.

Noise regulation

Noise regulation is carried out in two directions: hygienic regulation and regulation of noise characteristics of machines and equipment (technological).

The current noise standards at workplaces are regulated by SanPiN 2.2.4 / 2.1.8.10-32-2002 “Noise at workplaces, in residential, public buildings and in residential areas” and GOST 12.1.003. "SSBT. Noise. General requirements security."

In accordance with SanPiN 2.2.4 / 2.1.8.10–32–2002, maximum permissible noise levels are normalized in two categories of noise standards: noise limit at workplaces; Noise limit control in the premises of residential, public buildings and on the territory of residential development.

Maximum permissible sound levels and equivalent sound levels in workplaces

For an approximate assessment of noise, the sound level is taken, determined by the so-called A scale of the sound level meter in decibels - dBA.

These documents establish the permissible noise levels in working rooms for various purposes. At the same time, zones with a sound level above 80 dBA are considered dangerous, they must be marked with special signs, and workers in these zones must be provided with personal protective equipment.

The maximum sound level for fluctuating and intermittent noise must not exceed 110 dBA. In areas with a sound pressure level of more than 135 dBA, even a short stay of people is prohibited.

For various production equipment and machines, the standards set the maximum levels of noise characteristics (machines, compressors, weaving and other equipment).

There are also standards that establish methods for determining noise characteristics.

The standards stipulate that technical documentation the noise characteristics of the machines were indicated.

The fight against noise in production is carried out in a comprehensive manner and includes measures of a technological, sanitary-technical, therapeutic and prophylactic nature.

The classification of means and methods of noise protection is given in GOST 12.1.029–80 SSBT “Means and methods of noise protection. Classification”, SNiP II–12–77 “Noise protection”, which provide for noise protection by the following construction and acoustic methods:

a) soundproofing of enclosing structures, sealing the porches of windows, doors, gates, etc., arrangement of soundproof cabins for personnel; shelter of noise sources in casings;

b) installation of sound-absorbing structures and screens in rooms on the path of noise propagation;

c) the use of aerodynamic noise silencers in internal combustion engines and compressors; sound-absorbing linings in the air ducts of ventilation systems;

d) creation of noise protection zones in various places where people are located, the use of screens and green spaces.

Protection of workers from noise can be carried out both by collective means and methods, and by individual means.

Basic noise protection methods:

1. Source Noise Reduction

Causes: mechanical, aerodynamic, hydrodynamic and electromagnetic phenomena due to the design and nature of the machines, inaccuracies in manufacturing, etc.

To reduce noise at the source, use:

Replacement of percussion mechanisms with non-impact ones;

Use of low noise connections;

Replacing metal parts with plastic ones;

Replacement of rolling bearings with plain bearings

Changing operating modes;

Grease, etc.

These are the most effective measures, because. Dealing with noise after it occurs is more expensive and often ineffective.

2. Noise emission redirection

Appropriate orientation of installations in relation to workplaces or residential buildings.

This method is used in the case when a working device (machine, unit, installation) radiates noise in a direction. An example of such a device is a pipe for discharging compressed air into the atmosphere in the direction opposite to the workplace.

The attenuation of noise along the path of its propagation is provided by a set of construction and acoustic measures. These include rational planning decisions(primarily removing noise sources at an appropriate distance from objects), sound insulation, sound absorption and sound reflection of noise.

Noise attenuation measures should be considered already at the design stage. master plans cities, industrial enterprises and layouts of rooms in individual buildings. Thus, it is unacceptable to place objects that require protection from noise (residential buildings, laboratory and design buildings, computer centers, office buildings, etc.) in the immediate vicinity of noisy workshops and units (test boxes for aircraft engines, gas turbine units, compressor stations etc.). The noisiest objects should be combined into separate complexes. When planning rooms inside buildings, the maximum possible distance between quiet rooms and rooms with intense noise sources is envisaged.

To mitigate noise penetrating into isolated rooms, it is necessary: to use materials and structures for ceilings, walls, partitions, solid and glazed doors and windows that provide proper sound insulation; use sound-absorbing lining of the ceiling and walls or artificial sound absorbers in isolated rooms; provide acoustic vibration isolation of units located in the same building; apply soundproof and vibration-damping coatings on the surface of pipelines passing in the room; use silencers in mechanical ventilation and air conditioning systems.

The machine room of elevators is unacceptable to be located directly above and below the living quarters, as well as next to them. Elevator shafts should not be adjacent to the walls of living rooms. Kitchens, bathrooms, bathrooms should be combined into separate blocks adjacent to the walls of the staircases or to the same blocks of neighboring rooms, and separated from the living quarters by a corridor, vestibule or hall.

It is forbidden to install pipelines and sanitary appliances on the enclosing structures of living rooms, as well as to place bathrooms and sewer risers next to them.

In all public and sometimes in residential buildings, ventilation systems are used, sometimes air conditioning and air heating systems with mechanical equipment, can create significant noise.

To mitigate the noise propagating through the channels of ventilation, air conditioning and air heating systems, special silencers (tubular, honeycomb, plate and chamber with sound-absorbing material) should be used, as well as air ducts and spurs lined with sound-absorbing material from the inside (Figure 1). The type and size of the muffler is selected depending on required level noise, allowable airflow rate and local conditions.

Soundproofing rooms from airborne noise is called the attenuation of sound energy in the process of its transmission through the fence. Most often, soundproof fences are walls, partitions, windows, doors, ceilings.

Currently, multilayer structures are used in construction practice more and more often. In some cases, they make it possible to obtain significant additional insulation compared to single-layer structures of the same mass (up to 12–15 dB).

In ceilings, to ensure the normative isolation of shock and airborne noise, a floor is made on an elastic basis (floating floor) or soft roll coatings are used. The joints between the internal enclosing structures, as well as between them and other adjacent structures, must be equipped in such a way that during operation there are no cracks and crevices that weaken the insulation (Figure 2).

Figure 1. Vent silencers (diagrams):

a --- tubular; b - lamellar; in - cellular;

g - cylindrical.

To increase sound insulation, double doors with a vestibule are also used. Door porches are provided with elastic gaskets. It is advisable to line the walls in the vestibule with sound-absorbing material. Doors should open in different directions.

Double windows are better isolated from airborne noise (up to 30 dB) than paired windows (20-22 dB).

Rice. 2.

a - floating floors on a continuous flexible basis (1 - floor covering; 2 - prefabricated slab or monolithic screed; 3 - soundproof flexible gasket; 4 - the bearing part of the floor; 5 - plinth; b - floating floor on tape or artificial gaskets; c - ceiling with soundproof materials (1 - soft rolled floor; 2 - ceiling; 3 - plinth)

Recently, "sound-proof ventilation windows" have been widely used, which provide high sound insulation and at the same time allow ventilation of the room. These are two blank frames located at a distance of 100 mm or more from one another, with soundproof lining along the contour. Glasses of various thicknesses are used or a package of two glasses is used in one frame. A hole is equipped in the wall under the window, in which a box is installed in the form of a silencer with a small fan that provides air flow into the room.

Sound-absorbing structures are designed to absorb sound. These include sound-absorbing lining of enclosing surfaces of rooms and artificial sound absorbers. Sound-absorbing structures are widely used.

Most often, sound-absorbing lining is used: in educational, sports, entertainment and other buildings to create the best acoustic conditions for the perception of speech and music; in production shops, offices and other public premises (typing bureaus, machine counting stations, administrative premises, restaurants, waiting rooms of railway stations and air terminals, shops, canteens, banks, post offices, etc.); in corridor-type premises (schools, hospitals, hotels, etc.) to prevent the spread of noise.

Sanitary and hygienic requirements for sound-absorbing structures are, first of all, that they should not worsen hygienic conditions due to the shedding of fibers or material particles, and contribute to the accumulation of dust. The ease of cleaning dust from sound-absorbing structures is of particular importance in buildings with both increased sanitary and hygienic requirements (hospitals) and with increased dust emission (most industrial enterprises).

The effectiveness of sound-absorbing cladding in noisy rooms depends on the acoustic characteristics of the room, the characteristics of the selected structures, the method of their placement, the location of noise sources, the size of the room and the localization of the design points. Usually it does not exceed 6-8 dB.

Measures to combat urban noise can be divided into two groups: architectural and planning and construction and acoustic.

Noise reduction along the path of its propagation from the source to residential development involves rational design of the road plan, transverse profiles and the use of the right of way.

In this case, if it is impossible to provide a buffer zone from roads to buildings, taking into account the requirements of sanitary standards, the following options for reducing traffic noise can be distinguished (Figure 3, a-k):

Figure 3. Schemes for protecting residential buildings from traffic noise.

a - noise barrier on the right of way of the highway;

b - a combination of a noise barrier on the right of way and a barrier located on the dividing strip (with a small width of the dividing strip, it is combined with fences);

c - a retaining wall from the side located close to the building;

d - green spaces within the buffer zone;

d - protective earth shafts;

e - road in a recess within settlements;

g - a road on an overpass with a device on the dividing strip and along the edges of noise barriers made of transparent plastic. The space under the overpass can be used for parking. For better protection, you can build a low soil shaft;

h - gallery with natural light;

and - a gallery open in the opposite zone from the building using the space above the gallery for parking and additional noise protection with green spaces;

k - a tunnel with complete isolation from traffic noise and the use of space above the tunnel for local traffic.

Various administrative measures may be used. These include: redistribution of traffic flows by city streets; restriction of movement at different times of the day in one direction or another; composition change Vehicle(for example, a ban on the use of trucks and buses with diesel engines on some streets of the city), etc.

When developing urban planning and development projects for noise protection, it can be used as natural conditions(terrain and green spaces) and special structures (screens near highways). You can also apply rational methods of zoning the territory according to the conditions of the noise regime for certain types of buildings, plots and sites for recreation, household needs, etc. noise transport population reduction

Consider possible options noise protection in cities. First of all, in order to protect against noise in the design of cities and other settlements, it is necessary to clearly divide the territory according to its functional use into zones: residential, industrial (industrial), communal storage and external transport. Industrial (manufacturing) and communal storage areas, designed for large cargo flows along transport routes, are located so that they do not cross the residential area and do not wedged into it.

To protect against noise, when designing an external transport system, it is necessary to provide bypass railway lines in cities (for passing transit trains outside the city), place marshalling stations outside settlements, and technical stations and reserve rolling stock parks, railway lines for freight traffic and access roads - outside the residential area; to separate new railway lines and stations during new construction from the residential development of cities and other settlements of the SPZ; observe the proper distance from the boundaries of airports, factory, military airfields to the boundaries of residential development

When designing a street and road network, the maximum possible enlargement of Intermain areas, a decrease in the number of intersections and other transport hubs, and the installation of smooth curvilinear road junctions should be provided. In residential areas it is necessary to limit through traffic.

Functional zoning of the territories of microdistricts should be carried out taking into account the need to locate residential buildings and preschool institutions in areas that are the most remote from noise sources, highways, parking lots, garages, transformer substations, etc. In areas adjacent to noise sources, buildings can be built, in which allow higher sound levels. These are consumer services, trade, Catering, utilities, administrative and public institutions. Shopping centers and service blocks are usually built on the border of microdistricts along transport routes in the form of a single complex.

If residential development needs to be placed on the border of microdistricts along transport routes, it is advisable to use special types of noise-proof residential buildings. Depending on the insolation conditions, it is recommended to build: noise-protected residential buildings, the architectural and planning solutions of which are characterized by windows oriented towards noise sources auxiliary premises and no more than one living room without beds in multi-room apartments; noise-proof residential buildings with increased sound-proofing properties of external enclosing structures oriented towards noise sources and with built-in supply ventilation systems.

To ensure sanitary standards in apartments and on the territory of microdistricts, it is necessary to use compositional methods for grouping noise-proof buildings based on the creation of a closed space. When residential buildings are located along highways, one should not resort to compositional methods of grouping residential buildings, which are based on opening space towards the roadway.

If architectural and planning measures (breaks, building methods, etc.) do not provide the proper noise regime in buildings and on the territory of a residential microdistrict, as well as in order to save the territory necessary to comply with territorial gaps with highways, it is advisable to use building acoustic methods: noise protection structures and devices, screens, noise protection strips of landscaping, and for residential buildings also window openings with increased sound insulation.

Various buildings and structures can be used as screens: buildings with reduced noise requirements; soundproof residential buildings; artificial or natural relief elements (dredging, ravines, earth ramparts, embankments, mounds) and walls (roadside retaining, enclosing and noise-protective). Noise barriers should be placed as close to the noise source as possible.

Buildings with reduced noise requirements (consumer services, trade, public catering, utilities; public and cultural and educational, administrative and economic institutions) and noise-protected residential buildings should be placed along noise sources in the form of frontal, if possible continuous, development. Premises of administrative, public, cultural and educational institutions with increased requirements for acoustic comfort (conference halls, reading rooms, auditoriums of theaters, cinemas, clubs, etc.) should be built on the side opposite from noise sources. They are separated from the highway by corridors, foyers, halls, cafes and buffets, auxiliary rooms.

As an additional means of noise protection, special noise protection strips of green spaces can be used. Several strips are formed with gaps between them equal to the height of the trees. The width of the strip should be at least 5 m, and the height of the trees should be at least 5-8 m. On the noise protection strips, the crowns of the trees should be tightly closed together.

Send your good work in the knowledge base is simple. Use the form below

Students, graduate students, young scientists who use the knowledge base in their studies and work will be very grateful to you.

Hosted at http://www.allbest.ru/

Introduction

Man is surrounded by noise and vibrations or fluctuations from birth, and throughout his life is under their influence. Whether he rides a tram, bus, subway, or horseback, when he moves, he feels not only noise, but also vibrations; whether he is indoors or outdoors, he hears noises, sounds (conversation, music, etc.). As technology develops, noise increasingly surrounds a person in everyday life, so anthropogenic noise is one of the objects of environmental pollution. From the point of view of sanitary and hygienic conditions, noise and vibrations affect the cardiovascular and motor systems, cause dissipation and fatigue of a person, and reduce its functionality.

The problem of combating noise in all its manifestations in construction practice has been and remains relevant. She was especially aggravated in last years due to the significant increase in traffic. Thousands of cars take to the streets every day. Increased engine power, speed, which also caused an increase in traffic noise. The source of noise in residential and public buildings is street noise with its continuous and monotonous character. This noise is especially disturbing for those residents whose apartments or houses face the streets.

Soundproof buildings

If the building is located on the main street (highway) with a lot of traffic, which almost does not decrease during the day, then in this case it is in the most unfavorable conditions. In rooms located in buildings located on a square with squares with large trees, the noise is much lower, especially in summer, when the trees are covered with leaves.

In addition to street noise, noise sources in the building can be household noise: turning on the radio and other equipment at high power, loud conversations or repair work in the apartment. But there may also be noise from service mechanisms, for example, the operation of an elevator, an electric motor, malfunctions in the water supply system. The fact is that in cities built a large number of panel and frame-panel houses, which very well transmit any noise effect through the floors and rooms. Inside a residential building, in many cases, this is facilitated by abundant radio-technical stuffing, malfunction of the sanitary system, wall structures, for example, concrete houses and its ceilings. Therefore, experimental noise-protective houses are being designed. Such houses will protect from noise not only apartments, but also intra-quarter space.

There are two directions in the design of noise-protective multi-storey residential buildings. The first is connected with the improvement of the soundproofing properties of the enclosing structures of a residential building - external walls, windows and doors, the second - with the methods of planning a house, section, apartment.

Soundproof doors

In fact, any door is soundproof. True, while not every door protects against noise equally effectively. If only a few decibels need to be eliminated, a regular cardboard door will suffice. A door made of chipboard or PVC profile can get rid of noise of 27-30 dB. And this means that in this case, the driveway noise will not penetrate inside (the human ear does not perceive noise less than 15 dB). When we are talking For special rooms, such as, for example, recording studios, the doors are subject to higher requirements for sound insulation. True, it should be remembered that making the door more noise-resistant than walls and ceilings is pointless.

It makes sense to talk about a soundproof door only when the soundproofing of walls, windows and ceilings is properly provided. This is especially important for rooms with lightweight interior partitions (for example, from plasterboards), where you can put the most deaf door, but still everything that happens behind the partition will be heard. All other things being equal - the thicker and heavier the door, the better it protects against noise. For example, a thick lead door will not let in almost a single sound. But you must admit that it is absurd to put a door with such a weight in typical houses. A relatively light, within 80 kg, a chipboard or MDF door is able to protect against noise not exceeding 30-40 dB.

According to experts, a massive oak or pine door significantly reduces the noise level. In addition, fire doors have quite good anti-noise properties: a heat insulator is laid inside them, which is also a good sound insulator. For example, the sound insulation of fire doors of the German company Hermann is in the range from 36 to 45 dB.

Steel doors differ in soundproofing qualities if an insulator is laid between the steel sheets (ideally mineral wool). What is important to keep in mind is that without such an insulator, the steel sheet can, on the contrary, amplify the noise. And yet, if there is a desire and need to more reliably protect against noise, it is possible to make a noise-protective door out of the most ordinary door.

Rice. 2 - Steel doors

Reducing the sound transmission of a conventional door

The simplest way is to upholster the door with genuine leather or leatherette, laying a layer (or several layers) of synthetic winterizer or batting under the upholstery. At the same time, the thicker the “soft cushion” is, the less noise will pass through the door. It is best to beat the door on both sides. In addition, you can upholster the door with wood or a chipboard sheet, but remember that in this case the door becomes heavier and it is better to supplement it with one or two more hinges.

A more complex design option is when two doors are installed with a vestibule between them. The air layer in the vestibule will reduce the noise level to a large extent.

The sealing gaskets that close the gaps between the door leaf and the door frame also reduce the noise level well. They are attached to the door leaf in such a way that a protrusion forms on the door, covering the edge of the door frame. Such doors with sealing gaskets transmit noise by 30-40% less than usual.

Soundproof windows

Conventional double-glazed windows, which are used in PVC windows, can reduce the noise level by 31 dB. Soundproof windows have an additional aluminum profile on the outside. Soundproof windows are designed specifically for harsh operating conditions and exceed all the technical parameters of ordinary plastic windows. An additional chamber, which is formed due to the additional aluminum profile on the outside, not only perfectly fights noise, but also increases the thermal insulation of the room.

Noise screens

Noise barriers are made up of metal structures with polycarbonate panels. They can be mounted as a free-standing fence - with load-bearing columns and a foundation, or as an addition to an existing fence, increasing its height.

Features of noise barriers

The basis of acoustic screens is a metal stand and a polymer plate and polycarbonate, which performs a soundproof function. Due to the unique properties of this material, noise barriers are resistant to ultraviolet radiation, solutions of salts, acids, meadows and other chemicals. In addition, such plates do not change their properties over time, so the effectiveness of their sound protection does not decrease.

Noise barriers are very easy to install. If the panel design itself is done correctly, on average it takes no more than 10 minutes to install it. When installing noise screens, the most important thing is to place the canvases so that the acoustic tightness is not disturbed, and modern models can be rotated at any convenient angle without fear of this.

Noise protection characteristicsfences and noise barriers

According to their types, noise protection fences and screens are divided into noise-reflecting and noise-dissipating. An example of a noise-reflecting fence is a conventional concrete slab fence. Sandwich panel fence is a noise-dissipating fence. The use of noise-reflecting fences is not always possible, such fences, for example, cannot be installed along railways, since in this case, all the noise will be reflected back to the railway, which will affect the comfort of passengers. Noise-dissipating fences and screens, on the contrary, do not reflect, but absorb and dissipate noise, look aesthetically pleasing and modern, are much lighter in weight, and therefore require less reliable supports.

The main characteristic of a noise protection fence is the degree of noise reduction. In digital terms, this characteristic is expressed in decibels. For example, they say that a noise barrier reduces the noise level by 30 dB. Before ordering a noise protection fence, you should analyze the sources of noise that interfere with you and decide on the type and height of the fence.

Biopositive soundproof walls

Taking into account the greatest efficiency of noise protection and ease of construction on highways, biopositive noise protection walls are expedient. It is recommended to design them in such a way that the ratio of height to thickness of the cross section in the lower part of the wall is 3:1...5:1. Various designs of noise-protective landscaping retaining walls made of prefabricated or monolithic reinforced concrete have been developed. Structurally, they are reinforced concrete containers with holes filled with natural or artificial soil mixture with plants planted in it. The roots penetrate through the holes into the natural soil, so special watering is not required. On the facades of the greened noise-protective wall, after the plants have strengthened and grown, a continuous curtain of leaves (in the warm season) or climbing branches of plants against the background of reinforced concrete planes (in the cold season) is visible. For architectural expressiveness, it is recommended to provide noise-protective walls with a decorative surface (undulating relief, etc.).

Design options for noise-protective green walls:

Racks with a step of 4 ... 6 m, pinched in the foundation or soil, with inclined flat slabs of a relief surface inserted into their grooves. Through holes with a diameter of 5 ... 10 cm can be made in them, in which plants can also be planted;

Box-shaped elements installed one on top of the other and filled with soil, and on the facade parts natural slopes of the soil are visible, on which plants are planted;

Composite elements made of separate folds, mounted one on top of the other with filling the internal space with soil. Structurally, they are similar to box-shaped:

Triangular frames with a step of 4 ... 6 m, in the grooves of which vertically arranged flat slabs with a relief facade surface are placed. In this design, the backfill is a volume, the cross section of which increases from top to bottom.

Noise protection is carried out in these walls, firstly, due to the damping of massive reinforced concrete walls with soil filling; secondly, reorientation of the sound by the non-flat surface of the walls; thirdly, noise suppression by landscaping.

Noise barriers

For all settlements that are located close to highways or railway lines, the problem of high noise levels is common. In this situation, the owners of the estates are forced to escape from the loud noise by all possible means. Most often, a high solid fence is still not enough to protect your house and site, for this reason you have to resort to additional measures - to involve special structures and materials. One of the options for creating a noise-protective fence is multilayer panels. Their outer surfaces are represented by metal corrugated boards, and between them there is penoizol or mineral wool slabs. Such a panel simultaneously performs two functions - it reflects and simultaneously absorbs sound, that is, it is a complete noise protection system. In finished form, the panel is not for sale, it is already assembled on site by representatives of companies that specialize in the construction of fences. The height of the fence is calculated according to a certain scheme: an imaginary line is drawn between the point of the top of the roof ridge, as well as the alleged highest point of the location of the trucks on the road, which must be blocked by a fence. The upper part of the structure must be equipped with a sound baffle.

Noise protection measures

The solution should be sought through a preliminary analysis of the acoustic regime of the main areas, an assessment of the existing and predicted noise characteristics of the highway and the acoustic impact on the buildings of the first development front, as well as the development of noise protection measures that ensure the standard acoustic regime. In the real conditions of the reconstruction of the main streets, it is almost impossible to ensure acceptable noise levels in the adjacent territory of a multi-storey residential building, so the main emphasis should be placed on noise protection of residential premises and the preservation of the housing stock. At the same time, noise protection measures can make up a very significant share in the estimate of a city highway reconstruction project.

Acoustic calculation of the territories of the planned highways at the design stage allows minimizing the cost of noise protection measures. Known methods of acoustic calculation of territories according to SNiP II-12-77 "Protection from noise" and "Guidelines for taking into account the requirements for reducing noise levels in urban planning projects" involve grapho-analytical calculation of the noise characteristics of the highway with the construction of noise maps. Modern computer technologies make it possible to use effective methods for numerical calculation of noise pollution in urban areas. They involve numerical simulation of the noise propagation process, which is a computationally laborious task. An alternative is an approach based on the sampling of the study area and the energy summation of the noise at the study points using GIS. For some selected point on the territory, the summation of energy from discrete point sources is performed. The motorway is a linear source of noise and is represented as a collection of point sources. The calculation of noise energy propagation takes into account the effect of attenuation depending on the distance, as well as the diffraction and reflection of sound, i.e. the influence of sources that are not in the line of sight. This approach potentially leads to some decrease in the accuracy of calculations due to discretization. However, this shortcoming is compensated by the fact that all calculations can be carried out using the GIS itself, and this makes it possible to combine the solution of transport and planning problems with the assessment of the impact of noise pollution.

soundproof door screen soundproofing

Rice. 3 - Noise protection measures. Green spaces

Conclusion

Most urban areas are constantly marked by increased noise levels. The main source of noise pollution in the city is still motor transport, its share in the total noise is 70 - 80%. The next largest urban areas subject to this pollution and the level of noise are railway and air transport, construction sites and industrial enterprises. The problem of noise pollution has become acute in all major cities of the world.

Of course, it is impossible to completely get rid of this kind of pollution while living in the city. Ecology modern city implies, among other things, a system of measures to improve the acoustic comfort of its citizens. Street planning is ideally carried out taking into account sufficient distance between highways and residential buildings. Further, it is necessary to build high-speed bypass roads for transit transport, to correctly redistribute traffic flows from the city center to the outskirts. It is precisely because of the accumulation of a huge number of traffic flows that the central part is a kind of epicenter of noise pollution in the city. Scientists are improving noise absorption technologies, working on the creation of new noise-absorbing materials that could be used in noisy industries and in the construction of residential buildings.

Bibliography

1. Ecological alternatives to scientific and technological revolution. Oleinikov Yu.V. M., Nauka, 1987.

2. Cities and the environment. Space research. M., Thought, 1982.

3. Architecture industrial buildings. Mikheev A.P. M., Integral "A", 2006.

Hosted on Allbest.ru

Basic noise protection measures. Architectural and planning measures Noise protection measures along the railway

Noise barriers

Noise protection measures

Send your good work in the knowledge base is simple. Use the form below

Similar Documents