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Council under the President of the Russian Federation for the development of civil society and human rights. Noise control in the city The use of one or another method or a combination of them depends to a large extent on the degree and nature of the required noise reduction, taking into account

Federal Agency for Agriculture

Federal State Educational Institution
higher professional education

State University for Land Management

Department of Land Use and Cadastres

Noise in the city and means of protection

Completed: Art. gr. 22 to-2

Reshetnikova A.A.

Checked: st. teacher

Introduction

Noise pollution in cities almost always has a local character and is mainly caused by means of transport - urban, rail and air. Already now, on the main highways of large cities, noise levels exceed 90 dB and tend to increase by 0.5 dB annually, which is the greatest danger to the environment in areas of busy transport routes. Medical studies show that increased noise levels contribute to the development of neuropsychiatric diseases and hypertension. The fight against noise in the central areas of cities is hampered by the density of existing buildings, which makes it impossible to build noise barriers, expand highways and plant trees that reduce noise levels on roads. Thus, the most promising solutions to this problem are to reduce the inherent noise of vehicles (especially trams) and the use of new noise-absorbing materials in buildings facing the busiest highways, vertical gardening of houses and triple glazing of windows (with the simultaneous use of forced ventilation).

A particular problem is the increase in the level of vibration in urban areas, the main source of which is transport. This problem has been little studied, but it is certain that its importance will increase. Vibration contributes to faster wear and destruction of buildings and structures, but the most significant is that it can adversely affect the most accurate technological processes. It is especially important to emphasize that vibration brings the greatest harm to advanced industries and, accordingly, its growth can have a limiting effect on the possibilities of scientific and technological progress in cities.

The state of the problem of reducing traffic noise

An important problem of Moscow, like any other large city with a large amount of transport and industry, is the high level of noise, which, according to environmental scientists, causes a lot of trouble for Europeans.

Over 75% of the territory of the capital is under the influence of acoustic load 5-10 dB above the norm (55 dB during the day and 45 dB at night). At the same time, according to various sources, 3-6 million Muscovites live in areas of increased noise pollution, who are constantly exposed to noise equal to 90-100 dB during the day and 70 dB at night. According to experts, the most unfavorable situation has developed in the South Butovo, and the calmest - in the North-Western District.

The main culprit of noise, of course, is transport, which accounts for 70-90% of all noise pollution. So, due to the proximity of the Vnukovo airport, the areas of Solntsevo, Teply Stan, Yasenevo and Troparevo suffer the most. In turn, Sheremetyevo affects Mitino, Molzhaninovsky district affects Zelenograd, and Ostafyevo affects the same South Butovo.

In second place in terms of noise generated are industrial facilities that affect 10-15% of the capital's territory. In addition, there are many other sources of noise pollution: for example, elevators, heating units, boilers, pumping and switchboard substations. Therefore, it is not surprising that in the last 10 years, the majority of young residents of the capital have noticeably weakened hearing by the age of majority: they hear 5-20% worse than the norm, as if they were not 18, but 85 years old.

In general, methods for reducing traffic noise can be classified in the following three areas: reducing noise at the source of its occurrence, including the removal of vehicles from service and changing their routes; noise reduction in the way of its propagation; use of means of sound protection in the perception of sound.

The use of one or another method or a combination of them depends to a large extent on the degree and nature of the required noise reduction, taking into account both economic and operational constraints.

Any attempt to regulate noise must begin by identifying the sources of that noise. Despite the presence of significant analogy of various sources, they are quite dissimilar to each other for the three modes of transport,
- road, rail and air.

Of the three main modes of transport, road transport has the most adverse acoustic impact. Cars are the predominant source of intense and sustained noise that cannot be compared to any other. The noise generated by moving vehicles is part of the traffic noise. In general, the most noise is generated by heavy vehicles. At low road speeds and high engine speeds, the main source of noise is usually the power plant, while at high speeds, lower speeds and lower power plant power, noise due to the interaction of tires with the road surface can become dominant. In the presence of irregularities on the road surface, the noise of the spring suspension system, as well as the roar of the load and the body, may become predominant.

It should be noted the great importance of measures to limit the spread of noise that has already occurred, along with the main method of reducing road transport noise by suppressing the source of its occurrence. These measures include improved road design and routing, traffic control, the use of screens and barriers, and a review of general land use concepts near major highways.
An additional measure, which is applicable to all modes of transport, is to improve the design and soundproofing characteristics of buildings to reduce noise inside them.

Rail transport, in contrast to road and air, is not developing at such a rapid pace. However, there were signs that the railroads would take on a new role. After the introduction of high-speed trains in Japan and France, many countries decided to increase the speed of trains and the volume of passenger traffic, thereby increasing the competitiveness of railways. The expansion of the railway network and the increase in the speed of trains will cause an increase in noise and the associated problems of protecting the environment from it. Similar situations have already arisen in Japan, where the public protested against high-speed trains. As a result of these protests, the Japanese National Railways Administration decided to postpone the construction of new lines leading to Tokyo Narita Airport.

The annoyance caused by air traffic noise is mainly due to the introduction of jet aircraft on civil airlines in the late 1950s. Since then, the number of commercial and private jets in daily service has exceeded 7,000. During this period, significant attention was paid to reducing aircraft noise. The solution of the problem under consideration was carried out in the following three main directions. The first and probably the most important direction is to study the main sources of noise and the development, in particular, of less noisy power plants. The second direction is related to streamlining and introducing control of aircraft flights in the vicinity of airports. Finally, the third direction - measures not directly related to changes in the operating conditions of aircraft - the rational use of land both on the territory of the airport itself and in its vicinity with increased sound insulation of buildings and structures exposed to high-level noise.

Means and methods of noise protection

General classification of means and methods of noise protection.

It applies to the means and methods of noise protection used at workplaces of industrial and auxiliary premises, on the territory of industrial enterprises, in the premises of residential and public buildings, as well as in the residential areas of cities and towns.

1 Means and methods of protection against noise in relation to the protected object are divided into:

means and methods of collective protection;

· individual protection means.

2 The means of collective protection in relation to the source of noise excitation are divided into:

means that reduce noise at the source of its occurrence;

means that reduce noise on the way of its propagation from the source to the protected object.

2.1 Means that reduce noise at the source of its occurrence, depending on the nature of the impact, are divided into:

means that reduce the excitation of noise;

means that reduce the sound-emitting ability of the noise source.

2.2 Means that reduce noise at the source of its occurrence, depending on the nature of noise generation, are divided into:

means that reduce noise of vibrational (mechanical) origin;

means that reduce noise of aerodynamic origin;

means that reduce the noise of electromagnetic origin;

means that reduce the noise of hydrodynamic origin.

2.3 Means that reduce noise along the path of its propagation, depending on the environment, are divided into:

means that reduce the transmission of airborne noise;

means that reduce the transmission of structure-borne noise.

3 Noise protection means, depending on the use of an additional energy source, are divided into:

passive, which does not use an additional source of energy;

active, in which an additional source of energy is used.

4 Means and methods of collective noise protection, depending on the method of implementation, are divided into:

· acoustic;

architectural planning;

organizational and technical.

4.1 Acoustic noise protection, depending on the principle of operation, are divided into:

means of soundproofing;

means of sound absorption;

means of vibration isolation;

means of damping;

noise silencers.

4.2 Soundproofing means, depending on the design, are divided into:

soundproofing fences of buildings and premises;

· soundproof casings;

· soundproof cabins;

acoustic screens.

4.3 The means of sound absorption, depending on the design, are divided into:

· sound-absorbing facings;

volumetric (piece) sound absorbers.

4.4 Means of vibration isolation, depending on the design, are divided into:

Vibration isolation mounts

elastic pads;

Structural breaks.

4.5 Damping means, depending on the damping characteristic, are divided into:

· linear;

non-linear.

4.6 Damping means, depending on the type of damping, are divided into:

Elements with dry friction;

elements with viscous friction;

Elements with internal friction.

4.7 Silencers, depending on the principle of operation, are divided into:

absorption;

reactive (reflex);

combined.

4.8 Architectural and planning methods of noise protection include:

rational acoustic solutions for building layouts and master plans for facilities;

rational placement of technological equipment, machines and mechanisms;

Rational placement of jobs;

rational acoustic planning of zones and mode of movement of vehicles and traffic flows;

Creation of noise-protected zones in various locations of a person.

4.9 Organizational and technical methods of noise protection include:

· application of low-noise technological processes (change of production technology, method of processing and transportation of material, etc.);

equipping noisy machines with remote control and automatic control;

use of low-noise machines, changing the structural elements of machines, their assembly units;

Improving the technology of repair and maintenance of machines;

Use of rational modes of work and rest of workers in noisy enterprises.

5 Personal protective equipment against noise, depending on the design, are divided into:

Anti-noise headphones that cover the auricle from the outside;

Anti-noise inserts blocking the external auditory canal or adjacent to it;

anti-noise helmets and helmets;

anti-noise suits.

5.1 Anti-noise headphones according to the method of attachment to the head are divided into:

independent, having a hard and soft headband;

built into a headgear or other protective device.

5.2 Anti-noise earplugs, depending on the nature of use, are divided into:

Multiple use

single use.

5.3 Anti-noise inserts, depending on the material used, are divided into:

solid;

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Ministry of Education and Science of Ukraine

Odessa National Maritime University

on the topic: Problems of noise in cities

Performed:

Kiyutina A.A.

Odessa -2014

Introduction

3.2 Sound insulation of buildings

4.2 Freight car noise

Conclusion

List of used literature

Introduction

Noise pollution in cities almost always has a local character and is mainly caused by means of transport: urban, rail and air. Already now, on the main highways of large cities, noise levels exceed 90 dB and tend to increase by 0.5 dB annually, which is the greatest danger to the environment in areas of busy transport routes. Medical studies show that increased noise levels contribute to the development of neuropsychiatric diseases and hypertension. The fight against noise in the central areas of cities is hampered by the density of existing buildings, which makes it impossible to build noise barriers, expand highways and plant trees that reduce noise levels on roads. Thus, the most promising solutions to this problem are to reduce the inherent noise of vehicles (especially trams) and the use of new noise-absorbing materials in buildings facing the busiest highways, vertical gardening of houses and triple glazing of windows (with the simultaneous use of forced ventilation).

1. Trends in the acoustic impact of transport

Even in ancient Rome, there were legislative provisions regulating the level of noise generated by vehicles of that time. But only recently, since the early 1970s, when developing prospects for the development of transport, they began to take into account its impact on the environment. The environmental movement has become so powerful that many promising developments in the field of transportation have been recognized as environmentally undesirable. This ecological revolution did not occur as a result of the public's reaction to environmental pollution in all its manifestations, but as a result of a combination of increased public concern and the need to maintain environmental cleanliness at least at the current level due to the intensive development of transport systems and means, and urbanization. For example, road transport in the countries of the Organization for Economic Cooperation and Development (OECD) for 1960-1980. increased 3 times, air - 2 times. The urban population of these countries has increased by 50%, and the number of cities with more than 1 million inhabitants. doubled. During the same period, many roads, airports and other major transport facilities were built.

With such a development of transport, it is not surprising that the noise pollution of the environment has constantly increased.

But it should be pointed out that since the end of the 70s, mainly due to experimental studies related to the limitation of noise generated by personal vehicles and aircraft, and also partly as a result of the improvement of roads and soundproofing of buildings, the level of traffic noise previously achieved has tended to stabilize. .

Considering the trends in noise reduction for the next few years, we can conclude that there is an emerging improvement in the corresponding indicators. In OECD countries, trucks have more stringent noise requirements. The new rules should lead to significant changes that will particularly affect the part of the population that is exposed to the noise generated by heavy goods transport. In addition, some countries are introducing improved road design codes and legislation to give people whose homes are exposed to significant traffic noise the right to demand additional soundproofing measures in their homes.

By providing for more stringent measures to reduce vehicle noise at its source, further real reductions in human exposure to noise can be expected. Back in 1971 in the UK, when developing a project for low-noise heavy vehicles, it was recommended to proceed from the standard noise level of 80 dBA. Even if this project has demonstrated that the current technology achieves a certain degree of required noise reduction while being economically feasible, there are still technical and political difficulties in establishing legislative measures that would facilitate the implementation of the above design standards into production. It is estimated that if this technical policy could be implemented, the number of people exposed to noise of 65 dBA or more would be significantly reduced.

With regard to the noise generated by civil aircraft, according to most studies, the implementation of measures to reduce its impact will take quite a long time. This is due mainly to two reasons. Firstly, the new generation of aircraft will be less noisy, and secondly, all old-type aircraft that do not meet modern noise regulations will be taken out of service by the end of the next decade. The rate of renewal of the existing fleet will, of course, depend on many factors, mainly the rate of replacement of new generation aircraft, as well as possible delays due to the expected increase in the fleet of general aircraft and the use of helicopters. Taking these factors into account, the forecast for OECD countries indicates that in the United States there will be a decrease in the number of people exposed to 65 dBA noise by about 50-70%; in Denmark by -35%, and in France, according to the results of the estimated assessment in relation to the five most important airports, there will be a decrease in the area exposed to aircraft noise by -75%. While the number of people who would benefit from these interventions is small compared to the significantly higher number of people exposed to unacceptably high levels of ground transport noise, these interventions represent a significant step forward.

Quantitative indicators of railway noise exposure in most countries remain largely unchanged. The state of affairs in this area is expected to remain unchanged for the foreseeable future. However, there are areas where rail traffic noise is a major source of annoyance. The recent introduction of high-speed trains and high-speed urban lines leads to the expansion of areas exposed to new sources of noise. Therefore, people's living conditions can be improved if serious noise reduction measures are taken.

2. The state of the problem of reducing traffic noise

In general, methods for reducing traffic noise can be classified in the following three areas: reducing noise at the source of its occurrence, including the removal of vehicles from service and changing their routes; noise reduction in the way of its propagation; the use of means of sound protection in the perception of sound.

The use of one or another method or a combination of them depends to a large extent on the degree and nature of the required noise reduction, taking into account both economic and operational constraints.

Any attempt to regulate noise must begin by identifying the sources of that noise. Despite the presence of a significant analogy of various sources, they are quite dissimilar to each other for the three modes of transport - road, rail and air.

It is often difficult to determine the relative contributions of different noise sources in complex vehicles. Therefore, if the problem arises to reduce the noise of a given vehicle, valuable information can be obtained based on understanding the mechanism of noise generation of these sources when the operating conditions of the vehicle change. Due to the fact that the overall noise of the vehicle is determined by a number of sources, it is necessary to try to obtain data on the characteristics of the emission of each of these sources separately and determine the most effective methods for reducing the noise of a particular source, as well as which of the methods for reducing the overall noise of vehicles means will be the most economical in this case. It should be noted the great importance of measures to limit the spread of noise that has already occurred, along with the main method of reducing road transport noise by suppressing the source of its occurrence. These measures include improved road design and routing, traffic control, the use of screens and barriers, and a review of general land use concepts near major highways. An additional measure, which is applicable to all modes of transport, is to improve the design and soundproofing characteristics of buildings to reduce noise inside them.

3. Limiting road traffic noise exposure

3.1 Reduce traffic, improve road construction and regulate land use

Movement intensity.

The most obvious way to reduce road traffic noise is to reduce traffic as a result of traffic shifts. Dividing the traffic flow, for example, in half, generally leads to a reduction in traffic noise levels of 3dBA. However, the closure of sections of the road for all types of road transport can create certain difficulties. For example, when a general ban on motor traffic was imposed from 10 pm to 6 am in Nuremberg, about 600 preferential documents were issued for the right of normal access for residents, and the movement of motorists caused by these permits significantly weakened the effectiveness of this general ban.

The effect of a traffic restriction depends not only on the displaced traffic flow, but also on the intensity of traffic both before and after the restrictions are introduced. Reducing the traffic intensity by half leads to a decrease in the equivalent noise level, provided that other parameters remain unchanged. But the intensity of traffic and the speed of cars, generally speaking, are strongly correlated quantities. A decrease in traffic intensity is usually associated with an increase in the speed of movement, so the expected optimal gain from a decrease in traffic intensity is not achieved. In addition, the movement of the traffic flow leads to an increase in noise on other roads of the transport system. Nevertheless, the fact that the level of traffic noise and traffic intensity are related by a logarithmic dependence can be used in the right direction. For example, you can remove the traffic flow from a poorly used road and transfer it to an already heavily loaded one. This will result in a slight increase in noise on a heavily loaded road, especially if it was pre-designed for heavy traffic. At the same time, significant results will be achieved in reducing noise on lightly loaded roads. Therefore, very significant noise reduction for a significant number of people can be achieved by creating bypasses specially designed for high traffic volumes and reducing the tension of the transport network penetrating residential areas.

In large and small cities, where detours have not yet been created, you can switch traffic at night to the streets where trade enterprises are located.

Limiting the number of heavy trucks in the traffic flow is also aimed at reducing the noise of road transport. These measures usually take the form of bans on trucks from entering a certain area or on all vehicles above a certain weight capacity entering a city, as well as restrictions on entry at certain times, usually at night, Saturdays and Sundays.

Theoretically, reducing the speed of road transport is one of the most effective measures to reduce the noise level of road transport. On high-speed roads, reducing the average vehicle speed by a factor of 2 can lead to a reduction in the equivalent noise level of 5-6 dBA. But in practice it is difficult to achieve a reduction in the speed of cars. Despite the introduced speed limits, most vehicles exceed this limit.

Speed reduction advances can be made by providing raised pavement or transverse lanes to give drivers a sense of the vehicle's speed. Other methods include narrowing the road and bending the road alignment.

Road construction.

The noise emitted by road transport depends on both the vertical and horizontal contours of the road, as well as the type of road surface.

Issues of construction and design of roadside barriers are considered when designing a road. Typically, an acoustic barrier is in the form of a vertical wall, although other forms have been widely used, and attempts have been made to improve the aesthetic, rather than shielding, performance of the barriers. When designing an effective sound barrier, the following goals are set: the barrier must have sufficient mass to attenuate sound, be accessible for routine maintenance and repair; the installation of a barrier should not lead to an increase in accidents.

In addition, the construction of the barrier must be economical.

To ensure the optimum degree of sound protection, the barrier should be located close to the source of the noise or close to the object to be protected from the noise. The barrier should, if possible, completely hide the fenced section of the road, excluding the visibility of this section from the windows of the protected buildings or various points of the protected space. Although the mass of the barrier should not be significant, it is important to ensure that all gaps in the barrier structure are properly sealed. A hole or a gap in the barrier design can lead to a significant reduction in its screening capability, and the presence of these defects can cause resonant effects, which, in turn, can lead to a change in the nature of the sound converted by the barrier, in which there will be a change in broadband noise into noise containing discrete tones.

The sound energy generated by the traffic flow can be reflected using efficient sound receivers, which are equipped on the side of the barrier wall facing the source. If there are sound barriers on both sides of the road, further complications can arise due to multiple reflections occurring between the walls of the barrier. With certain configurations, the shielding potential of each barrier can be significantly reduced by the additional noise refracted through the barrier from imaginary sound sources.

Mention should also be made of barriers made in the form of an embankment, as well as barriers of the "cave" type in rocky ground. Typical absorber type barriers consist of hollow box-like panels that have a perforated or exposed metal plate on the side of the road. The box is then filled with sound absorbing material such as mineral wool.

Roads built in recesses are usually well screened by the edge of the screening wall, although reflections from a far wall can reduce the screening performance.

On embankment or overpass roads, noise problems are more severe, although there is some shielding at sound reception points below the edge of the embankment or parapet.

Calculation of road intersections.

In order to reduce noise levels, it is important to consider, at the design stage of a road crossing, how to manage the flow of vehicles in order to minimize the number of vehicle accelerations and decelerations. The same goal is set in the development of road traffic management plans. These plans are designed to shorten travel times and reduce accidents.

The traffic light system has been developed and installed in almost every major city in the world. Unfortunately, the impact on road noise from these measures is not as significant as expected. This is partly because the improvement in traffic management through the implementation of these control systems gradually leads to the fact that the load on the system increases, there is a rapid overflow and / or an increase in the intensity of traffic.

Another measure to limit the flow of vehicles passing through road intersections is to turn off traffic lights at road intersections with not very high traffic at night. However, this does not lead to any systematic reduction in noise levels and is due to the fact that the speed of cars is too high, which negates the benefits associated with the elimination of the process of starting cars in the presence of traffic lights.

Road surface design.

Through research, it has been found that some improvement in noise reduction can be achieved with an appropriate configuration of tread pattern and tire design. However, the design of tires with a significantly reduced noise level is in conflict with the urgent need to ensure traffic safety, prevent heating of the tread and ensure the economy of the car. Therefore, the creation of promising alternative pavement designs opens up great opportunities for noise reduction.

Important, from the point of view of limiting noise, is apparently the structure of the road surface itself; whether it is formed by a bituminous material with a random pattern of structure, or a concrete coating, with a dominant transverse structure.

In the UK, measurements have been taken that have established an elementary relationship between the resistance of a car to skid, realized on a given road surface, and the total noise level that is generated by cars traveling at high speeds on a given road surface. It was found that this ratio is statistically independent of the structure of the pavement material. Unfortunately, although this result is useful in setting standards for pavement design that take into account safety and environmental considerations, it exposes the contradiction that exists between the definition of pavements with low noise levels and satisfactory safety standards at high speeds. For example, a smooth road surface can be relatively quiet, but at the same time completely unsafe for driving in wet weather.

Some road surfaces combine low noise and satisfactory vehicle side skid resistance. Such pavements usually have a porous structure that is moisture permeable, but at the same time has satisfactory sound absorption in the frequency range from 400 Hz to 2 kHz.

Laying an experimental pavement on the corrugated surface of the concrete sections of the ring road east of Brussels resulted in a reduction in noise levels of approximately 4 dBA for vehicles traveling at a speed of 70 km/h and 5.5 dBA for a speed of 120 km/h h. It has been found that noise reduction can be achieved with other types of porous pavements. In Sweden, for example, such data were obtained for a porous pavement composed of a particle size-matched stone core with emulsion asphalt as a binder, and in Canada for a pavement composed of an "open" type mixture with a thin protective layer of bitumen. In the latter case, noise reduction was found to be 4-5 dBA compared to conventional asphalt pavement and 3 dBA compared to worn concrete pavement, which has much less lateral drift resistance than pavement composed of mixtures of "open" type and covered with a thin protective layer of bitumen.

However, in Norway and Sweden, there have been problems with the durability of these pavements caused by the use of studded tires during the winter months. These tires crush the surface layer into a fine powder, which then clogs the pores of "open" road surfaces, gradually reducing their sound absorption.

Land use planning.

The noise level near the highway is very significant. When a new vehicular route is found in an existing urban area, most of the existing facilities there must be retained, so road layout and design are critical to minimizing vehicle noise. In the event that the road passes through an area that has not yet been developed or is planned for redevelopment, consideration may also be given to limiting the impact of noise through appropriate land use management of the areas surrounding the road.

The possibilities for successful road planning are determined by the amount of space available, as well as the nature of the terrain and the applied zoning policy. When planning the road, it is necessary to ensure the greatest possible distance between the source of noise and the area most sensitive to noise; rational siting of places of human activity that are compatible with some noise impacts, such as car parks, open spaces, buildings and household devices; the use of architectural and building forms and green spaces as barriers to shield areas sensitive to noise.

Residential areas can be protected from road traffic noise by placing them at a sufficient distance from the noise source. However, designers consider this approach economically unreasonable. Often this is true, since, for example, in buildings located next to a highway (less than 100 m), the noise level rarely drops below 70 dBA. However, under certain circumstances, the spatial separation of buildings and roads should be considered as the only positive solution to the problem. This is especially true in areas of heterogeneous redevelopment or development in an area where blocks of high-rise buildings are being built that cannot be easily shielded by barriers and must be located as far from the road as local conditions allow.

Low-rise residential buildings can, in most cases, be protected from noise by some form of screening or green space.

3.2 Sound insulation of buildings

Building design

The need for costly building envelopes with high soundproofing characteristics can be minimized if the shape and orientation of the building is planned taking into account the impact of road noise.

The purpose of this approach is to avoid reflected sounds from any wall surface facing noise-sensitive areas of the building itself, or from a nearby building. The shape of the building can be used to provide its own acoustic protection. Some parts of such a building (stepped walls and balconies) provide acoustic protection from road noise.

Inside any building, there are rooms where people will be less exposed to outside noise, since noise from the road is usually the only irritant for rooms facing the road directly, it is necessary to identify noise-sensitive rooms and place them on the other side of the building.

Soundproofing of building elements.

The physical characteristics of walls that contribute to good sound insulation are low stiffness, high damping and high mass. Thus, a thick stone wall will have higher sound insulation than a thin glass panel.

The noise generated by road traffic often has high levels in the low frequency range, when the sound insulation of the building envelope is usually determined by the mass of the building envelope.

A two-layer construction will have greater sound insulation than a single-layer construction of the same total mass. For example, a hollow brick wall will have a higher sound insulation than a solid brick wall. The sound insulation of a two-layer building envelope depends on the physical characteristics of each of the layers and on the nature of the connections between them. The further apart the layers are and the less the connection between them, the better the sound insulation of this two-layer fence will be. The propagation of sound through the framing structure can be reduced if so-called lip seals are used for this at least for one of the layers. The sound insulation of two-layer building envelopes can be improved by filling the gap between the layers with a sound-absorbing material such as fiberglass.

There should be no light opening elements in the wall, such as doors and windows, as their poor sound insulation will reduce the soundproofing properties of the building envelope. But buildings are rarely designed with this consideration in mind, as windows provide natural light, ventilation just as much as visual contact with the outside.

Double-layer building envelopes in the form of double glazing can significantly improve sound insulation. The most important factor in determining the effectiveness of double glazing is the gap between the composite glass panels. Increasing the gap to 200 mm results in an overall greater sound insulation.

If the glass sheets are not installed in parallel, a slight improvement in sound insulation can be obtained both in the region of coincidence of wavelengths and in the region where the cavity resonance effect is observed. However, the overall noise reduction obtained by tilting one of the sheets of glass rarely justifies the extra cost of constructing the building envelope. transport noise city

A similar improvement in sound insulation can be achieved by sticking strips on the contour of the opening window. However, a clean opening of the window may impair the ability of such strips to completely cover the gaps along the contour. When you open a window to ventilate the room, the sound insulation drops sharply.

With tightly closed or sealed windows, natural ventilation cannot be used. You need either a mechanical ventilation system or an air conditioning system. Such systems must be carefully selected to provide adequate ventilation without exceeding acceptable noise levels. The ventilation outlets and inlets of these systems must not face the road. They must be equipped with baffles or shields in order to block the propagation of noise.

The roof of a building is usually the only significant vehicular noise path when the building is below road level, or the roof has a gradual slope where a large area of the roof is directly exposed to the noise. In the roof of any structure, there are usually many air gaps that change the sound insulation. It could be provided even with the help of a heavy tile covering. Any openings in the roof (chimneys or chimneys) will contribute to the propagation of noise. If these holes are not very significant, they should be sealed. But in most cases, ventilation in the roof cavity is important, so these holes should be located on the side of the building that does not face the road, or these holes should be equipped with a grill or soundproof canopy.

4. The problem of noise reduction from railway transport

4.1 Noise reduction in wheel-rail interaction

Two opposite methods can be proposed to reduce the noise emitted by the interaction of the complex and the rail.

The first of these methods is reduced to the maximum possible reduction in the unevenness of the wheels and rails. In this case, the greatest effect is achieved by eliminating irregularities in one of the indicated elements, the irregularity of which is large. With this approach, there is a decrease in the variable component of the force of interaction between the wheel and the rail. This method gives the best results in practice. This involves keeping the rail surface free of undulating wear and using disc brakes to reduce the formation of bumps on the wheel tread. It is also possible to use some types of shoe brakes in which cast iron shoes are replaced with composite material brake shoes, although these shoes will still act on the wheel tread. This replacement of the pads helps to reduce rolling noise, since wavy bumps will not form on the wheel surface.

With the second method, one can try to reduce the response of the noise emitting elements. The most obvious way is to increase the damping of the wheels or rails. Such an attempt was made when looking for measures to reduce the rattle of the wheels when passing curved sections of the track. However, this attempt did not lead to any significant reduction in noise when the wheels roll along a straight or curved section of the track with a large radius. The reason for the failure of this attempt is not clear, but it can be assumed that the friction that occurs at the site of the contact dent already exceeds the value of the additionally introduced damping.

Another method was also tried to reduce the emitted noise by installing an acoustic screen on the body in the form of aprons covering the bogies. The effect of this method was also insignificant: the largest noise reduction was 2 dBA. The complexity of aprons is that usually they cannot be made low enough to completely screen out wheel noise due to the strict limits of the installed gauge of the rolling stock to prevent collisions with various track devices. In addition, if the theory that the rail is the main source of noise emission is accepted, then wheel shielding is unlikely to lead to a significant reduction in noise.

Another possible solution is to install extended acoustic screens along the track. However, there is doubt about the effectiveness of acoustic screens installed close to the track. Typically, acoustic baffles are only effective when their height is approximately greater than the wavelength of the sound propagating in the direction of the baffle. Therefore, it can be assumed that the screens will be effective only in the region of the upper frequencies of the wheel-rail interaction noise spectrum, and even then only in the case when each railway track is surrounded by acoustic screens on both sides.

4.2 Freight car noise

For operational reasons, the freight car suspension system should be as economical as possible. The consequences of this are obvious. Freight cars are built relatively crudely, without proper measures to limit their rattle and rumble. The damping of the spring suspension system is usually insufficient, and vibrations can be freely transmitted to the car body. Moreover, the cars are noisier when they are empty than when they are loaded: the load leads both to mass stabilization and to some damping.

Technical means can be proposed to reduce the noise of freight rolling stock to the level of noise of passenger cars, but their implementation will encounter a number of obstacles. Studies show the possibility of reducing the noise level of freight cars with disc brakes by 5 dBA. However, there are usually other strong arguments in favor of retaining cast iron drum brakes, in addition to the considerations associated with the modification of the brake system. Changes in braking force depending on the speed of movement in relation to the two considered brake systems are significantly different. Therefore, the use of freight cars with different brakes in the same train cannot be allowed. Consequently, the operation of international freight trains with their usual re-formation and diversity of cars requires that all cars, new or old, of any accessory, have the same brake system.

Reducing the noise level of rattling and roaring, as well as the elimination of resonant modes of vibration of the bodies of the rolling stock does not present any particular technical difficulties, but the implementation of appropriate measures is costly. Likewise, the use of a more advanced spring suspension system or freight wagons equipped with bogies, rather than the use of extended wagons with two axle wheelbases, results in grinding in curved sections of the track. The conversion of old freight cars to new modern running gear is associated with high costs.

5. Reducing the impact of noise from air transport

5.1 Aircraft noise mitigation

Introduction of restrictions on the operation of aircraft

Airspace controls developed in a number of countries reduce the impact of noise generated by aircraft by restricting their operation during certain times of the day. The practical implementation of these measures comes down to limiting the time during which aircraft flights are allowed at the airport. At Geneva International Airport (Switzerland), with the approval of the Federal Office of Civil Aviation, a restriction has been introduced on take-offs and landings at night between (from 22.00 to 06.00) for all types of air traffic.

There are also examples of partial restrictions on nighttime take-offs and landings, and in this case we are talking about airports where the administration allows certain types of operations at night based on the type or class of aircraft. For example, at Palm Beach International Airport in Florida, scheduled takeoffs of noisy aircraft are prohibited from 10 p.m. to 7 a.m.

Some airports have restrictions on the total number of operations performed in a certain period of time. For example, London Heathrow International Airport allows 3,650 night-time aircraft operations throughout the summer, while Gatwick Airport allows 4,300 operations during the same period.

Restricting the operation of aircraft during certain hours of the day is considered the most stringent type of noise control in the industry. These restrictions can have significant economic implications for air transport, especially when air travel involves multiple time zones. Nevertheless, some types of partial or complete restrictions on the operation of aircraft during certain hours have been introduced at airports in many countries.

perimeter rule.

This rule is used to limit the range of flights departing from a given airport. Flight range can affect the level of noise generated in various ways.

First, it can determine the capacity of a particular airport. In general, fewer operations result in less overall noise exposure. With limited flight ranges, the maximum take-off weight of an aircraft is less, since it is determined mainly by the reserves of the required fuel. A lower takeoff weight allows for greater lift, which in turn results in a smaller noise contour generated by an aircraft on the ground. Finally, the type of aircraft required for shorter range flights may not be as noisy as the aircraft used for longer ranges.

This procedure requires some attention, especially in cases where there are closely spaced airports operating without such restrictions. John Wayne Airport in California has a range restriction that allows flights up to 500 miles. But there are other airports in the Los Angeles region that could serve aircraft without these restrictions. Thus, the application of such a procedure is very limited, and its legal side may be questionable.

Flight routes with minimal noise.

Consider special flight routes for takeoff and/or landing conditions that avoid overflying noise sensitive areas. The flight path in this case is a projection onto the plane of the earth's surface of the spatial flight path of the aircraft. This term is used for both takeoff and landing. In order to reduce the irritating effect of noise, it is necessary to link the selected flight routes with the position of the aircraft in space relative to the earth's surface or the territory used for residential construction.

At many airports, courses are prescribed for aircraft that are in the zone of uninhabited land, including water spaces, agricultural land, forest and steppe tracts or open spaces.

This makes it possible to significantly reduce the impact of noise on the populated areas of the capital.

Noise emission standards.

In general, the noise generated by each aircraft operation must comply at one or more points with the specified limits. As a rule, in practice, the maximum noise level measured outside the boundaries of the airport and related to any type of aircraft in operation is used.

Sanctions for violations of established noise limits can be very diverse.

Often, airlines that commit such violations are issued warnings without any legal sanctions. More common, however, is the imposition of a fine, as the violation is often a legally punishable act.

Noise control.

It has long been proved that it is possible in principle to monitor compliance with established noise limits at airports around the clock based on permanent measuring equipment, and the interest of airport administrations in the installation and use of such equipment and devices is increasing over time.

5.2 Noise mitigation (ground-based activities)

Flight intensity limitation

Such restrictions set a limit on the number of aircraft operations at an airport that can be carried out within a certain period. These restrictions include the regulation of the number of takeoffs and landings of transport aircraft permitted at a given airport during the day. For example, only 37 transport aircraft operations are allowed at Washington National Airport from 7:00 a.m. to 9:59 p.m.

There is a trend to provide incentives to those airlines that make extensive use of noise abatement measures and low-noise aircraft types with the aim of overall reducing the adverse impact of aircraft noise. However, it should be noted that limiting the volume of flights based on aircraft operating criteria, such as noise levels, has a significant impact on traffic volumes and airport capacity.

Airport capacity.

The capacity of an airport is determined by the number of flights and/or passengers carried over a given period of time (usually a year). The main reason for establishing capacity limits is to limit aircraft noise impact on those areas of the airport where staff and passengers are concentrated.

John Wayne Airport has a capacity limit of 4.75 million for the number of passengers carried. in year. By 2005 it is planned to increase it to 8.4 million people. in year. The number of actual operations is a more flexible value and is based on the emitted sound energy.

Airlines are not allowed to increase traffic in the future unless less noisy aircraft are put into service on the airlines. Traffic volumes may be increased provided that 43.9% or more of the intended operations are classified as low noise, or the airport noise targets are met. This somewhat controversial noise reduction policy is being reviewed by the US Federal Aviation Administration. According to the US authorities, noise limits may be set at local airports as a reasonable means of achieving noise reduction goals. However, such restrictions should not create serious obstacles to the development of interstate air traffic and international economic relations. Noise restrictions themselves cannot be unjustifiably discriminatory.

Ground racing engines.

Many airports are equipped with devices for the maintenance and repair of aircraft. An integral element of this process is the mandatory static testing of engines in certain modes of thrust or power.

Additional sources of noise may be auxiliary power units, power supply units, as well as other auxiliary equipment. Such races, depending on the location, time of day, type of aircraft and device used, can lead to adverse noise impacts on areas adjacent to the airport.

Much of the work involved in engine racing is done during non-flight times. This means that heavy aircraft maintenance work often takes place at night or early in the morning, which in turn creates real inconvenience for the population located near residential areas. Noise restrictions have been introduced at 94 US airports during overhead engine races.

Aircraft towing.

Aircraft towing to reduce noise impact is not a widely used procedure, although it is commonly used during maintenance and repair of aircraft engines. Aircraft are towed to a dedicated engine ground race stand with all systems turned off prior to testing, which also saves on fuel costs. This raises problems associated with the risk of damage to the chassis and other auxiliary systems. In the US, this method of noise reduction is no longer practical. Nevertheless, a return to this method is possible, which is completely determined by the ratio of benefits and costs in solving problems of safety and reliability, energy, and noise reduction.

Noise fees.

The administration of a number of European airports holds the lead in setting noise charges. This approach is based on the principle that aircraft operators pay, in separate fees, an amount proportional to the noise generated by the aircraft.

5.3 Rules governing land use near airports

General plan for the development of the airport.

A general plan, usually referred to as a structural or master plan, is usually an official document that is negotiated and adopted by the local government. This plan is a guiding political document in solving the issues of development of a particular area, it regulates the procedure for land use. Such plans are long-term and are designed for 10-20 years.

The general plan covers the issues of private land use, the placement of public buildings and installations, as well as the development of transport links. All three of these elements predetermine the solution of land use issues, taking into account various interests and possible consequences for the environment. Accounting for residential noise, along with other environmental factors, is an important part of effective and comprehensive planning.

The overall urban development plan should take into account not only the existing, but also the future interests of the airport development. The master plan for the development of the airport should be an integral part of the master plan for the development of the area. Both of these plans, unfortunately, are often developed independently of each other. Guidelines for land use, taking into account the overall interests of airport development, based on the levels of actual noise generated, are being developed in the United States for both military and civilian airfields.

Choice of building location.

It is important that when choosing a site for construction, which may potentially be subject to the adverse effects of noise, measures to reduce it are provided. Such an approach, in turn, requires the approval of a certain procedure for discussing the relevant project in public organizations in order to correctly take into account, along with other environmental factors, and subsequently include provisions governing the land use planning process. In such a procedure, it is necessary to consider the placement of buildings and measures for the use of natural or artificial acoustic screens. However, it should be emphasized that the formal process that governs noise control requirements at the government level is not yet widespread.

...

Effects of noise on health

It is difficult to overestimate the impact of noise on human health. Noises depress the nervous system, interfere with concentration, tire, cause irritability. Constant presence in the zone of noise pollution leads to sleep disturbances and hearing impairment. Noise exposure can even cause mental disorders.

The magnitude of noise exposure is different for each person. The highest risk group includes children, the elderly, people suffering from chronic diseases, residents of busy city areas around the clock, living in buildings without sound insulation.

With a long stay on busy avenues, where the noise level is about 60 dB, for example, while standing in a traffic jam, a person may have impaired cardiovascular activity.

Noise protection

WHO recommends a number of measures to protect the public from noise pollution. Among them is a ban on construction work at night. Another ban, according to the WHO, should concern the loud operation of any acoustic devices, both at home and in cars and public institutions located not far from residential buildings.
Noise must be dealt with!

The methods of resisting noise pollution include acoustic screens, which have recently been widely used near highways, especially in Moscow and the region. Soft asphalt and electric vehicles, unfortunately not yet widespread, are also ways to combat acoustic pollution in cities. To this list, one can add soundproof insulation of apartment buildings and landscaping of city squares.

Legislative acts in the field of noise control

In Russia, from time to time, interesting studies of the problem of noise in urban-type settlements appear, but at the federal, regional and municipal levels, there are no adopted special-purpose legal acts to combat noise pollution. To date, the legislation of the Russian Federation has only separate provisions on the protection of the environment from noise and the protection of humans from its harmful effects.

In many European countries. America and Asia have special laws. It's time for our turn to come. The Russian Federation should adopt a special law and by-laws on noise and economic instruments to combat it.

It is possible to resist the noise even now

If the residents of the house have an understanding that the noise background and vibrations exceed the maximum permissible level (MPL), they can apply to Rospotrebnadzor with a claim and a request for a sanitary and epidemiological examination of the place of residence. If, based on the results of the check, an increase in the maximum permissible limit is established, the violator will be asked to ensure the operation of the technical equipment (if it was he who caused the excess) in accordance with the standards.

It is possible to apply to regional and local administrations of settlements with the requirement of noise-protective reconstruction of the building. The tasks of combating sound pollution of the environment can also be solved at the level of individual enterprises. So anti-acoustic systems are built near railway lines, close to industrial facilities (for example, power plants) and protect residential and park areas of the city.

The fight against intense noise in the residential area of cities, in urban dwellings is one of the most urgent problems of protecting the human environment. This factor, especially as a result of the rapid growth in the number of urban vehicles constantly migrating throughout the city, affects almost continuously the entire population, interfering with the normal life of citizens not only during the day, but even during night rest hours. City noise has become a factor of great social importance.[ ...]

In the fight against traffic noise, not only engineering and technical solutions are used, but also organizational measures: prohibition of sound signals, flights over the city of air vehicles, restriction of movement, takeoffs and landings of aircraft at airfields located near populated areas at night, etc. [...]

In order to combat industrial and other noise, in particular, the following should be carried out: the introduction of low-noise technological processes; improving the design of vehicles and their operation, as well as the maintenance of railway and tram tracks, highways, street surfaces; placement of airfields and airports, industrial and other structures and equipment that are sources of noise, at the required distance from settlements and residential areas; improving the planning and development of cities and other settlements; organizational measures to prevent and reduce household noise.[ ...]

The creation of low-noise vehicles, such as electric cars, steam cars, cars with improved engines, high-efficiency mufflers and afterburners, should also contribute to reducing noise in the city. However, the powerful automotive industry, which produces hundreds of thousands of cars and buses of existing designs, cannot be rebuilt in a short time to produce new types of urban transport, as well as quiet trucks and buses. An analysis of domestic and foreign data on the forecast for the development of urban transport allows us to conclude that until the end of our century, new silent cars or electric cars will not be able to replace the entire fleet of modern cars. Therefore, in the next 40-50 years, in the fight against urban traffic noise, first of all, means of architectural planning and construction should be used.[ ...]

The need to combat noise is determined by the Decree of the Supreme Soviet of the USSR "On measures to further improve nature conservation and rational use of natural resources" dated September 20, 1972. On October 3, 1973, the Council of Ministers of the USSR adopted a special resolution “On measures to reduce noise at industrial enterprises, in cities and other settlements” No. 726. GOST No. 19358-74 “Automobiles, road trains, buses, motorcycles, scooters, mopeds and motorbikes. External and internal noise. Maximum permissible levels. Measurement methods”, chapters of “Building norms and rules” - “Planning and development of cities, towns and rural settlements” (SNiP P-60-75), “Residential buildings” (SNiP P-L.1-71) and other regulatory documentation.[ ...]

These are the results of the fight against "thingism" - just one of the examples of the wrong social orientation in meeting needs. The number of such examples can be greatly multiplied. It is worth mentioning at least two more. The lack of proper noise control in cities increases the overall incidence of the population by 30%, reduces life expectancy by 8-10 years, reduces working capacity by at least 10%, and the efficiency of recreation is almost doubled, etc.1. The consequences of such a phenomenon can not be commented on. The second example is agriculture, in general, the complex of nature management in Central Asia. Incorrect land use policy in the region has led to a shift in ethnic processes, economic anomalies, the destruction of normal labor needs, severe environmental disasters, deregulation of demographic mechanisms, a fatal violation of people's health, open and hidden unemployment and other acute problems. At the same time, the process develops and intensifies itself.[ ...]

Noise pollution in cities almost always has a local character and is mainly caused by means of transport - urban, rail and air. Already now, on the main highways of large cities, noise levels exceed 90 dB and tend to increase by 0.5 dB annually, which is the greatest danger to the environment in areas of busy transport routes. The fight against noise in the central areas of cities is difficult due to the density of buildings, due to which the construction of noise barriers, the expansion of highways and the planting of trees are impossible. The most promising solutions to this problem are to reduce the inherent noise of vehicles (especially trams) and the use of new noise-absorbing materials in buildings facing the busiest highways, vertical gardening of houses and triple glazing of windows (with the simultaneous use of forced ventilation).[ ...]

The role of greening the city as a means of combating air and noise pollution is growing. Each tree in the city absorbs an average of 30-40 kg of dust per year, and with an active crown - up to 65 kg. But not only dust, but also gases are captured by trees - in a year a tree is able to remove harmful substances emitted by a car over 25 thousand kilometers. With the correct location of green spaces, noise reduction reaches 20-30%. At the same time, irreversible changes occur in the trees: chlorosis and necrosis of foliage and needles was noted on 10-15% of the trees. Studies at the cellular level have shown that almost all trees are sick. With a further increase in transport emissions, in 10-15 years, most of the existing arrays will perish. To avoid this, first of all, it is necessary to develop new effective methods for planting trees and shrubs, to expand the network of protected forest park zones. The activities proposed by city organizations are aimed at increasing the provision of green spaces from 17.8 to 24 m2 per person.[ ...]

The book states that the growth of the city is accompanied by the development and concentration of industrial production, which are combined with the continuous development and introduction of new substances, preparations, materials and products from them into all areas of the economy and everyday life of the population. Along with this, freight and passenger traffic is significantly increasing. All this leads to the fact that a large amount of chemicals harmful to human health is emitted into the atmosphere of cities, and the soil and water of open reservoirs are polluted. The influence of air, water and soil pollution on the living conditions and health of people is shown. A system of measures is given to protect the air basin of the city, to protect water bodies from pollution by urban runoff, and soil from clogging with waste. The issues of combating urban noise and measures to protect the residential area from intense noise impacts are also considered. The instrumental and calculation methods of sanitary research in the field of sanitary protection of the environment of a modern city are indicated.[ ...]

Urban planning measures to combat noise and vibration are of great importance, especially when designing new microdistricts and cities. In the existing urban development, their effectiveness is limited.[ ...]

Courier Younee magazine rightly says: "Noise is the scourge of the modern world and an undesirable product of technical civilization - every day more and more intrudes into our existence." Progressive scientists of the world claim that noise in big cities shortens a person's life by 8-12 years. That's why the fight against urban noise is vital.[ ...]

The establishment of sanitary norms for permissible noise levels and spectra allows the development of technical, planning and various urban planning measures aimed at creating a favorable noise regime that meets hygienic requirements in residential buildings, residential areas, quarters, and in premises for various purposes. The norms of permissible noise levels are of great importance for noise control in residential areas of cities, since they define measures aimed at reducing noise from various sources.[ ...]

According to the report of the British Advisory Council on the problems of combating noise in industrial enterprises and on the streets of cities, high noise levels are the cause of frequent headaches, insomnia and nervous breakdowns in thousands of English people. The authors of the report draw attention to the inefficiency of measures to limit noise at enterprises, motorways and streets of settlements in England.[ ...]

Although automation in Czechoslovakia has not yet reached such a high level as in a number of other countries, noise in some places in large cities reaches an unacceptable upper limit (100-110 dB). Railway transport is a serious disturber of silence in cities. Another source of noise is some new industrial production, such as concrete factories, equipped with powerful vibrators and other concrete compaction equipment. The decisive factor confirming the need for an effective fight against noise is not only the increase in its intensity, but also its spread to new territories and spaces, as well as the constant reduction of the interval of night calm. The territory of Czechoslovakia is densely populated, so the noise from aircraft flying along the air corridors, as well as from airfields scattered throughout the territory, is a very significant problem.[ ...]

If one or more noisy workshops are located on the territory of the enterprise, then it is recommended to concentrate them in one or two places, as far as possible from other industries. When the enterprise is located in the city, noisy production should be located at a considerable distance from residential buildings. This noise reduction measure is called the rational planning of enterprises and workshops.[ ...]

In the USSR great attention is being paid to the protection of atmospheric air. The Directives of the 24th Congress of the CPSU read: “Strengthen work to improve the sanitary condition of settlements and the environment. To this end, speed up the construction and reconstruction of treatment facilities for industrial and domestic wastewater, gas-cleaning and dust-collecting installations, and take measures to combat noise and air pollution in cities with exhaust and car gases. It is envisaged to take measures to reduce the emission of pollutants into the atmosphere and to rationally locate industrial enterprises. Special factories have been set up to manufacture appropriate equipment for trapping industrial waste that pollutes the air. This equipment is installed in thousands of enterprises. So, for example, at the Dneprodzerzhinsk cement plant, dust collection measures have led to the fact that the dust in the air has decreased from 300 tons per day to 16.5 tons.

Noise is understood as a disorderly combination of sounds of different frequency and intensity (strength).

In order to eliminate acoustic discomfort in cities resulting from high noise levels, the state and local governments are implementing a set of measures to reduce noise, both at the sources of its occurrence and along its propagation paths. In the Republic of Kazakhstan, there are sanitary standards that strictly regulate the maximum permissible noise levels at enterprises, streets of cities and towns, in residential areas, recreation areas, areas of new buildings, as well as at workplaces. Violation of the established standards is dangerous to human health and therefore unacceptable.

An important condition for protecting the population from noise exposure is the strict observance of the established maximum permissible levels. One of the main ways to combat noise is to reduce it at its source.

Currently, there are standards for the removal of residential buildings from sources of car noise, the construction of airports, and a sanitary protection zone is being created around them, depending on the class of the airport.

Taking into account the noise generated during sports competitions, it is planned to remove sports facilities from the residential building at a certain distance, based on the types of sports and the location of the housing. At the same time, the presence or absence of green spaces, the number of storeys of the building and the layout are important.

The fight against noise, therefore, is a struggle for human health, for the creation of normal working, living and recreational conditions for him. A comprehensive solution to all these and other issues and problems allows us to successfully deal with noise in cities.

In order to select and apply more effective ways and methods to combat noise, a noise map of the city is compiled in each city, which is the main source material.

A noise map of a city (residential area, microdistrict or residential group) is compiled based on the results of measuring noise on the streets and roads of the city, based on a study of traffic conditions or the prospect of increasing traffic intensity, the nature of traffic flows for both existing and planned cities.

To compile a noise map, they study the intensity of traffic on the streets and roads in both directions of cars per hour, the average speed of the flow (km / h), the number of freight transport units in the stream (in% of the total number of cars in the stream), the presence of rail transport.

The noise level is measured by a sound level meter with microphones installed 7 meters from the carriageway, i.e. 5 meters from the curb (international standard) .

Previous materials:

Council under the President of the Russian Federation for the development of civil society and human rights. Noise control in the city The use of one or another method or a combination of them depends to a large extent on the degree and nature of the required noise reduction, taking into account

Federal Agency for Agriculture

State University for Land Management

Department of Land Use and Cadastres

Introduction

The state of the problem of reducing traffic noise

Means and methods of noise protection

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With such a development of transport, it is not surprising that the noise pollution of the environment has constantly increased.

2. The state of the problem of reducing traffic noise

The use of one or another method or a combination of them depends to a large extent on the degree and nature of the required noise reduction, taking into account both economic and operational constraints.

Any attempt to regulate noise must begin by identifying the sources of that noise. Despite the presence of a significant analogy of various sources, they are quite dissimilar to each other for the three modes of transport - road, rail and air.

3. Limiting road traffic noise exposure

3.1 Reduce traffic, improve road construction and regulate land use

In large and small cities, where detours have not yet been created, you can switch traffic at night to the streets where trade enterprises are located.

Speed ​​reduction advances can be made by providing raised pavement or transverse lanes to give drivers a sense of the vehicle's speed. Other methods include narrowing the road and bending the road alignment.

Road construction.

The noise emitted by road transport depends on both the vertical and horizontal contours of the road, as well as the type of road surface.

In addition, the construction of the barrier must be economical.

Roads built in recesses are usually well screened by the edge of the screening wall, although reflections from a far wall can reduce the screening performance.

On embankment or overpass roads, noise problems are more severe, although there is some shielding at sound reception points below the edge of the embankment or parapet.

Calculation of road intersections.

Important, from the point of view of limiting noise, is apparently the structure of the road surface itself; whether it is formed by a bituminous material with a random pattern of structure, or a concrete coating, with a dominant transverse structure.

Some road surfaces combine low noise and satisfactory vehicle side skid resistance. Such pavements usually have a porous structure that is moisture permeable, but at the same time has satisfactory sound absorption in the frequency range from 400 Hz to 2 kHz.

Land use planning.

The physical characteristics of walls that contribute to good sound insulation are low stiffness, high damping and high mass. Thus, a thick stone wall will have higher sound insulation than a thin glass panel.

The noise generated by road traffic often has high levels in the low frequency range, when the sound insulation of the building envelope is usually determined by the mass of the building envelope.

4. The problem of noise reduction from railway transport

Some airports have restrictions on the total number of operations performed in a certain period of time. For example, London Heathrow International Airport allows 3,650 night-time aircraft operations throughout the summer, while Gatwick Airport allows 4,300 operations during the same period.

perimeter rule.

This rule is used to limit the range of flights departing from a given airport. Flight range can affect the level of noise generated in various ways.

Similar Documents

Effects of noise on health

Noise protection

Legislative acts in the field of noise control

It is possible to resist the noise even now

Speed reduction advances can be made by providing raised pavement or transverse lanes to give drivers a sense of the vehicle's speed. Other methods include narrowing the road and bending the road alignment.