Typical pavement designs for urban roads pdf. Road clothes: definition, design. Typical designs of pavement of urban roads. Varieties of pavement
Approved by order of the Minister of Housing and Communal Services of the RSFSR No. 210 of April 15, 1980
Moscow Stroyizdat 1984
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FOREWORD 1. GENERAL PROVISIONS 2. BASIC PRINCIPLES OF CALCULATION OF TYPICAL CONSTRUCTIONS OF ROAD CLOTHES 3. DESIGN OF ROAD CLOTHES OF URBAN ROADS Indication of permissible axle loads on the road surfaceWhen designing a new or reconstructed pavement, traffic forecasts should be considered. Design Principles for Sidewalk StructuresThe surface of the reconstructed road must be individually designed. Design pavement in areas of operation. In mining operation areas, the surface must be individually designed, depending on the mining area defined in separate rules.Principles of road design and related equipmentReconstruction of the pavement should be preceded by testing and assessment of the technical condition of the surface structure and the substrate. Protecting the road from water damageDrinking water from the road. Emergency trips through the dividing strip should have a pavement structure, such as a roadway, with a configuration that allows vehicles to move from one road to another and provide effective drainage of surface water. No objects and devices should be placed on emergency start, with the exception of the barrier, which should be easily collapsible, without the difficulty of complex traffic on the road.4. PROVISION OF FROST RESISTANCE OF ROAD CLOTHING 5. SIDE STRUCTURES ATTACHMENT. TABLE OF CALCULATION OF DESIGNS OF ROAD CLOTHES SPEED ROADS, HIGHWAY STREETS AND ROADS OF TOTAL CITY VALUE HIGHWAY STREETS AND ROADS OF DISTRICT VALUE Non-rigid pavement designs In the area of \u200b\u200bdesignated road trips, depending on the needs of rescue services or road maintenance units, emergency trips should be provided from the road passing through each road. Emergency access must comply technical requirements for fire roads, as defined in separate regulations. The distance traveled from the road must be determined in accordance with local conditions. Parking lots for vehicles carrying hazardous materialsParking stands for vehicles carrying hazardous materials should not be located in hollows, wetlands and less than 10 meters from ditches, wells and drainage facilities. Parking stalls for vehicles transporting hazardous materials should have a separate, rigid drainage system equipped with devices for receiving and neutralizing spills of hazardous substances. The surface of the parking lot for vehicles carrying hazardous materials must be hardened, impermeable and prevent the entry of hazardous materials into soil and drainage equipment. Hard pavement designs INDUSTRIAL AND WAREHOUSE ROADS Non-rigid pavement designs Hard pavement designs LIVING STREETS AND LOCAL ROADS Non-rigid pavement designs Hard pavement designs The formation of parking stands for vehicles carrying hazardous materials should prevent the spread of any leakage of hazardous materials outdoors. Parking spaces for vehicles carrying hazardous materials should be brought to the attention of technical parametersspecified in certain provisions regarding fire roads. Parking for vehicles carrying hazardous materialsDepending on the needs and in agreement with the competent head of the State Fire Service of the Voivodeship, parking lots for vehicles carrying hazardous materials can be located. Parking spaces must meet the requirements specified in § 116 and the design of the parking lot should provide for the need to provide it with fire-fighting equipment, materials and means of neutralizing the quantity and type agreed with the competent office of the State Fire Service. IN-QUARTER DRIVES AND PEDESTRIAN STREETS Non-rigid pavement designs VILLAGE STREETS Non-rigid pavement designs Sidewalks Non-rigid sidewalk structures taking into account the arrival of heavy special vehicles weighing up to 8.5 t The construction of hard sidewalks, taking into account the arrival of heavy special vehicles weighing up to 8.5 tons. Rescue water supply in the alleyEmergency gates should be located in certain places, providing access to the water supply and fire routes. The hardened door must be delivered to the emergency door. Platforms for emergency columnsThe class road must have platforms designed for emergency towers. The platform must have dimensions of at least 1, 5 m at 1, 0 m, and access to it from the side of the road must have a width of at least 1, 0 m and be adapted to the disabled. If the platform is located on the edge of the road crown on the embankment with a height of more than 1, 5 m, it should be installed on the side of the slope on the handrails.Non-rigid sidewalk structures taking into account arrival of special vehicles weighing up to 6 t Hard sidewalk constructions taking into account arrival of special vehicles weighing up to 6 t Hard sidewalk structures without special vehicles LIST OF REFERENCES |
Foreword
In the XI five-year period in our country there is an intensive development of automobile and urban public transport, an unprecedented scale of housing construction and the associated growth of cities and towns. The decisions of the XXVI Congress of the CPSU and subsequent Plenums of the Central Committee of the CPSU provide for increasing the pace and improving the quality of construction of city roads and sidewalks, as well as increasing their durability.
Safety of the use of facilities and equipment in the alley
Treadmills and equipment for participants traffic must ensure the safety of their use, including of persons with disabilities. Road and road connections Chapter. . The pavement structure of the pavement is described in the following paragraph. Two sidewalk structures are recommended as follows: 3 cm of sand or sand asphalt, 10 cm of broken or natural aggregate or masonry; 8 cm concrete block wear layer on a sandy layer of 5 cm medium or fine-grained.
For these purposes, the Academy of Public Utilities named after K.D. Pamfilov created typical designs of road pavements of city roads and sidewalks, in the development of which cand participated. tech. Sciences Timofeev A.A. (KD Pamfilov Academy of Public Utilities), Ing. Novikov K.L. (Leningrad Institute of the Academy of Arts named after Pamfilov), Ph.D. tech. Sciences Smirnov M.M. and engineer Noskov V.G. (Ural Institute of the Academy of Arts named after KD Pamfilov), Ph.D. technical science Sheikhet I.M. (Rostov Institute of AKH mm. K.D. Pamfilova) and engineer. Baranov D.P. (Institute Giprokommundortrans).
The basis of pavement
In the case of pavement structures, the provisions of the Regulation contain only recommendations and not strict requirements, and road managers are free to use other pavement structures - for example, thicker base or asphalt or mastic asphalt instead of poured or sandy asphalt. This is a very important fact, since the above rule is a state of knowledge of the last century, when in fact there was no Polish bicycle infrastructure. The experience gained in the operation of structures recommended in paragraph 1 of Appendix 5 is accumulated.
1. General Provisions
In connection with the intensive development of cities in our country, the need arises to build a wide network of modern urban roads with hard surfaces, mainly from asphalt concrete and cement concrete.
The quality of urban roads to a large extent depends on the operation of freight and passenger road transport, as well as the cost of transportation. The condition of urban roads also affects traffic safety.
These structures do not provide the same pavement life. Consequently, the Directorate General of National Roads and Highways - the Faculty of Research, the Faculty of Research in Krakow, the team for bicycle paths - prepared a document entitled “Opinion on typical bicycle road surfaces”.
The authors note that although most major city councils with the most extensive experience in building and maintaining bicycle infrastructure have already adopted local design rules for using asphalt sidewalks on bicycles in small towns, concrete block. The “Opinion on Typical Bicycle Road Covers” aims at synthesizing the presentation and systematization of bicycle road lanes. In this regard, the authors note that their opinion relates to bicycle lanes of significant transport or major tourist routes.
The structural elements of the clothing of urban roads make up the most expensive and crucial part of the overall road construction. To ensure the durability of the pavement, it is necessary that the stresses arising in its structural elements with the repeated action of the wheels of passing vehicles do not cause significant permanent deformations that violate the stability of the pavement and the evenness of the surface of the coating necessary for movement at high speeds. The main condition for the durability of the pavement is the conformity of its design to the category of street and road, the actual and prospective traffic intensity, climatic and soil-geological conditions.
In this case, it is useful to solve the typical cube or asphalt dilemma. On the other hand, this does not preclude the use of other sidewalks, especially in special situations - for example, concrete sidewalks on buildings or gravel surfaces on bicycles for walking outside the road system through park or forest areas.
What are the arguments for the cube or asphalt dilemma? One of the important arguments is related to the functionality of the bicycle lanes, expressed by the energy that a cyclist must pass in order to overcome the route of a particular surface. The concrete path is higher than the rolling resistance asphalt, which is very important in the case of bicycles, which are only the strength of the cyclist. The authors note that the difference in rolling resistance means that using more energy, like a cyclist on an asphalt surface, will go further.
The pavement designs used in practice are not always the most economical, since in most cases only one or two or three design criteria are used for their calculation instead of four or five.
In Moscow, Leningrad, Kiev, Izhevsk, Tashkent and other cities, various local standard designs are used to design urban pavements. An analysis of them shows that not in all cases they meet the basic conditions of longevity. Often the design of urban roads is carried out by non-specialized organizations, which sometimes leads to gross errors and a sharp decrease in the durability of roads. An incorrectly designed construction of urban roads on the performance indicators of urban and road transport also has a harmful effect. As a result, there is a need for large additional investment in various types of repairs.
Varieties of pavement
This increases the range of cycling and increases the competitiveness of the bike against car communications. On the other hand, the construction of bicycle paths from the ankle means not using the potential of the bicycle as a vehicle, but, therefore, less users of the created infrastructure and less efficiency of the funds spent. In addition, the results show that the concrete surface of the road surface causes a much greater vibration of the bicycle than the asphalt surface.
Therefore, there was an urgent need to develop typical designs of urban pavements that meet modern traffic conditions in various climatic zones of the RSFSR. The basis for calculating pavement was the possibility of replacing it with a choice of finished structures, taking into account the soil, soil-geological and climatic conditions of the construction area, a given category of city roads, streets, the availability of local materials, work conditions, traffic conditions for automobile and passenger vehicles.
Continuous bicycles on concrete pavements will jeopardize the health of cyclists, even if they are equipped with shock absorbers. Another important fact associated with the ankle is that concrete is intuitively recognized as the surface of the sidewalk. Its use on bicycles causes conflicts between cyclists and pedestrians and illegally parked vehicles.
Basic concept of pavement
The authors of the article, considering the arguments against the ankle or asphalt and behind them, analyze the costs of their implementation and maintenance. They also indicate the advantage of asphalt. They also argue for foreign experience. For example, in Denmark only asphalt pavement. A satisfaction survey conducted by the Danish Road Administration shows that, in principle, only cyclists usually accept only those that are usually accepted.
It is recommended that the proposed standard designs be clarified by taking a more detailed account of local conditions and the cost of road-building materials so that on this basis a choice is made of the most feasible technical and economic solution for the construction of pavement or pavement.
The following typical designs of clothes for urban roads and sidewalks are classified depending on their urban importance, i.e. on the category of roads, the location of the road or sidewalk in a particular climatic zone, the most characteristic strength indicators of the soil base (elastic modulus) and, finally, on the type of pavement (non-rigid or rigid type.).
Both functional and economic rooms clearly indicate mechanical asphalt surfaces as optimal. Random arguments for a specific one are not yet backed up by any hard data. According to the authors, appropriately designed and made asphalt pavements are more convenient, safer, more durable, easier to read for the user and cheaper than concrete sidewalks.
Alexander Buchinski, Marcin Hila, Master. A directory of suspicious and semi-rigid surfaces and regulations for the design of public roads report the so-called. However, typical layout solutions for sidewalk layers do not contain too much detailed information and do not always adequately adapt to current traffic conditions. The main criterion for choosing the right design in accordance with the Catalog is the traffic category, which reflects traffic density, especially heavy traffic.
Pavement designs in the I road-climatic zone, taking into account its features (the presence of permafrost or a very large depth of freezing of soils in combination with high humidity and the need for heat-insulating and frost-protective layers) are highlighted separately.
Pavement designs that can be used simultaneously in the II and III road-climatic zones or in the IV and V zones having a small difference in the thickness of the structural layers are usually combined in one table.
In practice, however, the approach to choosing the type of sidewalk is not always the right one. In the case of city streets, in most cases cross-sections of the curb road are designed. There are two typical types of borders - concrete and stone. For financial reasons, it is recommended to build a street in specific borders. Stone products are used in more representative places, such as squares in markets or streets in the city center.
An exception may be official and internal roads for the movement of trucks. For heavy highways heavy curbs should be used, as on the roads there is often a problem with curbing trucks and vans. In such situations, a border width of 15 cm wide can be quickly damaged. Small defects do not significantly affect the durability of the entire pavement structure, however, destruction or damage to the entire structure can lead to damage to the upper surfaces of bitumen pavements and, as a result, to the gradual destruction of the entire structure.
A number of structures that can be used in all road-climatic zones with the difference in thicknesses of individual structural layers established by calculation are given in the summary tables of typical structures.
IN annex the most common pavement designs are given that allow the widespread use of traditional and local road-building materials and their compositions. In addition, the greatest simplicity and affordability of the manufacture and placement of asphalt concrete and cement concrete mixtures and products in pavements are taken into account.
In some calculations performed by the Giprocommundortrans Institute, the cost criterion was also used, which makes it possible to evaluate a number of equally strong structures with their minimum cost.
However, the economic criterion, in view of the presence of different belt prices for road-building materials and products, the scarcity of many materials for certain regions of the country, large and uneven transport costs, and the lack of a reliable criterion for the durability of structures of pavements and sidewalks, was not fully considered.
The appearance of conventional road surfaces, through which traffic is carried, conceals a complex structure of several layers. Each layer has its own device rules, characteristics and technological purpose. Provided that all layers are of high quality, a safe and durable coating can be obtained. This will be the pavement, which thus forms the basic infrastructure for the movement of cars.
Basic concept of pavement
The basis of roads is most often asphalt concrete and cement concrete. In both cases, the characteristics of the binder components, fractions of crushed stone, sand, and other fillers can vary. Actually, the finished structure of such coatings can be considered as a full-fledged pavement. The definition provides a common set of layers of a given coating, but each layer acts as a separate technological component, for the device of which special requirements are made. To ensure the reliability of the coating, it is necessary to ensure the conditions under which the stress arising in the structural elements from traffic does not have a destructive effect on the structure. This can be achieved by a rational calculation of the structural characteristics that technologists produce before the start of road work.
What is taken into account in the pavement design?
Typical designs They are developed as universal coatings for both city roads and country roads. It does not matter if it is a highway or a street. In the development of the project, the level of traffic intensity, the properties of the materials used, the loads, hydrological and soil conditions, as well as other factors affecting the operation of pavements and foundations are taken into account. On roads with non-rigid coatings, structures with a small volume of stacked layers are provided. In particular, the design of pavements of this type involves the calculation of the permissible deflection of the pavement in unfavorable, from the point of view of external conditions, periods of the year. Reversible deflection is calculated according to one basic characteristic - the elastic modulus.
The resistance of the upper layers is also taken into account. earthen soilon which the foundation will be laid later. For this parameter, technologists introduce the magnitude of the shear stress. If in one of the layers deviations from the norm of equilibrium, from the point of view of shear, can lead to residual deformation processes, the design of the pavement may include changing the composition by adding new plasticizers and technical components that increase the rigidity of the base fabric.
Varieties of pavement
All typical designs of pavement are divided into two categories - rigid and non-rigid. Moreover, each technological model of the coating device involves the use of specific indicators of moisture, thickness, size of the sand fraction, gravel and, in general, the properties of the cement-sand base. So, the elastic modulus of the soil base, depending on the design used, can average 300-500 kgf / cm 2. As an exception, designs that do not involve the construction of a sand layer for drainage can be cited. In this case, the design of non-rigid pavements designed for laying in sandy and sandy soils is carried out. The modulus of elasticity of such a base can reach 1200 kgf / cm 2. Designs differ in the number of technological layers. This can be a compacted two-layer clothing, and a coating of 5-6 layers. Depending on the external conditions, project developers can add additional layers, for example, with the function of an insulator.
Typical pavement designs
An important component in the improvement of urban infrastructure is the sidewalk. Its coating also refers to varieties of pavement, but, of course, with other technical and operational characteristics designed for pedestrian traffic. The structures of sidewalks in different regions do not differ so much from each other, since climatic conditions have a lesser effect on their surface. Nevertheless, the design takes into account the category of the street, its purpose, the intensity of pedestrian traffic, the characteristics of the soil base, as well as the ratio of the sidewalk to the roadway. In a standard form, the construction of pavement can be implemented in conditions of reinforced soil using asphalt and cement mortars. In some cases, ceramic and asphalt concrete slabsas well as weak based on natural stone. In this case, laying can be performed in several layers, as is the case with ordinary roads.
The basis of pavement
Perhaps this is the most crucial part of the overall design, since it lays the function of the ligament of the top cover with the ground, as well as the distribution of loads. In practice, the application provides a reduction in stress from the effects of the wheels, translating the power potential into the ground. Thus, the base due to the ground cover creates a kind of depreciation effect. But not always pavement has suitable characteristics of the base, from the point of view of protection, from external influences. For example, the lower layer may have optimal working qualities, but under the influence of water will gradually erode. Conversely, it can demonstrate resistance to climatic influences, but at the same time it is poor to perform load distribution. In order to optimize different characteristics, builders also distinguish functional layers in the base structure. So, the bearing part and auxiliary layers are separately considered. In such a structure, the base coat is responsible for mechanical resistance, and additional coatings counteract the same deposits.
Top part
The outer surface also performs a number of critical functions, the main of which is the direct reception of loads from cars. Direct contact also takes place in relation to climatic precipitation, therefore the protective qualities in the upper part can be called universal. The multifunctionality of the outer coating is achieved due to several layers, as in the case with the base part. So, in order to increase the resistance to cracks in the coating, special layers are used, which may include a geogrid and geotextiles, as well as modified cementitious components. On the surface, pavement has a special treatment, which also protects the coating from moisture and snow. In addition to protective qualities, the adhesion properties of the surface are also strengthened. Special treatments, for example, are also used to increase roughness and improve road and wheel adhesion.
Additional layers
Depending on the operating conditions, various negative factors can affect the road surface. Not every typical design can meet increased loads, in terms of thermal, hydrological and mechanical effects. For example, non-rigid road pavements are highly drainable and do not need additional sand decks, however, their strength properties may require reinforcement. To do this, interlayers are created between the bearing part and the upper layers, and technological layers of the polymer film are laid between the substrate and the ground.
Frost-resistant layer
In terms of adverse climate impacts, the most damaging is frost. Protection in case of operation in low temperature conditions involves the use of granular materials, including slag and crushed stone. A kind of insulation can also be a soil base on which pavement with base layers is formed. However, to prevent freezing, land cover is not enough - it is supplemented with reinforced cementing elements, as well as water-repellent embankments and non-porous materials.
Drainage layer
Technological layers of this type are used in areas with subgrade from non-draining soil. Mandatory inclusion of such layers is considered in regions with heavy rainfall. The main function of the drainage layer is to ensure drainage. In addition, typical designs of road pavements of urban roads, in which the drainage layer is higher in relation to the freezing depth, should be made only of durable and frost-resistant materials.
Technological defects
Breaks are considered the most dangerous phenomenon that can lead to improper use of pavement device technology. In such cases, there is a risk of complete destruction of the web over the entire thickness with the manifestation of sharp distortions of the structure profile. Less dangerous are the processes of peeling and chipping, which suggest surface damage due to the peeling of the binding elements and the loss of individual particles of mineral filling. Common mistakes with which typical designs of pavements are stacked can also cause shifts and the formation of potholes. The formation of open abysses also leads to the extrusion of soil to the surface, which makes the coating unsuitable for use.
Conclusion
In recent years, paving technology has changed little. The introduction of new solutions into the industry mainly affects technical support in the form of the appearance of modern machines, tools and equipment for the preparation and laying of different layers. The materials from which pavements of city roads are arranged remain the same. The base coatings are also cement filling, sand with gravel and binders. Of course, new modifying components with additives are being introduced more and more often, but they are of a point-like nature of increasing operational properties and do not radically change the characteristics of typical designs.
