Учебное пособие 1988

which passes through the mesh cells of the CPF coarse purification; 16 is the border between the gap 12 and the first in the direction ofthe gas flow filtering layers of the CPF of fine purification.

At the first stage of operation, natural gas enters through the inlet pipe 2 (Fig. 2 and 4) and passes through the side surface of an uncontaminated coarse filter cartridge 7 made of woven metal

mesh with a mesh sizebгр.n= .m=a . Large solid particles with a diameter of more than dч, which

1 n=1

are in the gas, settle on the outer surface of the rough CPF 7, and particles with a diameter

dч bгр.n=1.m=an=1 or less pass through its cells. Further, the gas flows through the side filte-ring surface of the layers 11 of the fine cartridge 8, first in the direction of the gas flow, having cells

with a sizebт.n=1.m=an=1 dч . Solid particles with a diameter dч bгр.n=1.m=an=1,equal to freely pass through the layers 11 of the fine cartridge 8, first in the direction of the gas flow, having

cells of the sizebт.n=1.m=an=1 dч , and settle in their thickness. Since the fibers of the first layers

11 are made with a diameterdт.n 1.m=an 1 dч /2, and their total thickness Sт.n 1.m=an 1 2dт.1

will be greater than the diameter of particle 15, i.e., Sт.n 1.m=an 1 dч as shown in fragment A in Fig. 4, particles 15 will not protrude with their center of gravity beyond the boundary 16 of this layer and, as a result, fall into the lower part of the gap 12.

At the i-th stage of operation, in the process of clogging of the rough purification CPF 7, the size of the cells decreases, and only particles of diameter dч. i pass freely through them less than dч, but no longer pass particles with a diameter equal to dч. Further, particles with a diameter dч. i less than dч are fed to the first layers 11 of the fine cartridge 8 in the direction of the gas flow. Then the gas passes through the side filtering surface of the first in the direction of gas flow lay-

ers 11 of the cartridge 8 of fine purification, having a cell sizebт.n=i.m=an=i > dч.i . Solid particles

with a diameter bт.n=i.m=an=i > dч.i freely pass through the cells of the layers 11 of the fine cartridge 8, first in the direction of the gas flow, and settle in their thickness.

Given that according to [3, 6], the fine CPF clog up several times slower than the coarse CPF, the diameter of solid particles at the i-th stage of the operation will always be less than the cells,

the first layers 11 of the fine filter cartridge 8 in the direction of gas flow, i.e., bт.n=i.m=an=i > dч.i . Hence in the gap 12 between the CPF of coarse and fine purification at any stage of the operation, a continuous layer of particles does not form, clogging the cells of its lower part, as a result of which the throughput of the CPF does not decrease. According to the results of this proposal,

61

Russian Journal of Building Construction and Architecture

a positive decision was received on the grant of a patent on 02/04/2020 on application No. 2019132265 with a priority from 10/11/2019.

In order to test the possibility of eliminating the settling of solid particles in the lower part of the gap 12 between the CPC of coarse 7 and fine 8 purification (Fig. 2) and maintaining the capacity, theTCSwas manufacturedandthen testedintheexperimentalcenter ofJSC“Giproniigaz”(Saratov) with a diameter of D = 160 mm with a coarse-purification CPFC based on a high-precision metal mesh with a square cell of 0.2 mm in compliance with GOST 6613-86. For testing, air with sand particles of 0.25 in size was employed as a working medium; 0.22; 0.2; 0.1; 0.05 mm. In this case, the proportion of fractions with sizes over 0.2 mm was 70 % in the total mass of impurities, andtheproportionoffractionswithsizesequalto0.2mmorlesswas30.0%[3].

Fine filter cartridges with a minimum cell size of the last layer of 0.04 mm in the direction of gas flow were made in two versions.

First option. The filtering cloth of the cartridge is made on the basis of a high-precision mesh with the number of layers equal to seven in accordance with GOST 6613-86. The mesh number

in the row n, the size of the square cellsbт.n=1.m=an=1 , the wire diameters dт.n 1.m=an 1 of the finecleaned CPF for option 1 are presented in Table. 1. At least the first two layers 11 in the direc-

tion of gas flow have cells sized bт.n=1.m=an=1 bгр.n=1.m=an=1, i.e., 0.22 > 0.2 mm. Solid particles

with a maximum size equal to dч bгр.n=1.m=an=1 , i.e., dч=0.2 mm passing from the coarse filter cartridge freely pass through the first two layers 11 in the direction of the gas flow of the fine cylindrical element 8, have cells sized bт.n=1.m=an=1 dч . The metal wires of the meshes of the

first two layers 11 are made with a diameter dт.n 1.m=an 1 more than half of the maximum di-

ameter dч/2 of the solid particles 15, i.e.,dт.n=1.m=an=1 dч /2.

Table 1

The mesh number in the row n, the size of the square cells and the wire diameters dt.

for CPF fine purification according to option 1

62

Then the layer thickness of the first two metal wires Sт.n 1.m=an 1 2dт.n=1.m=an=1 will be larger

than the particle diameter15, i.e., Sт.n 1.m=an 1 dч or 0.24>0.2mm. As the thickness Sт.n 1.m=an 1

exceeds the maximum diameter dч of a solid particle 15, i.e., Sт.n 1.m=an 1 dч , as shown in section А in Fig. 4, it does not project its center of gravity beyond the boundary 16 of this layer and, as a result, does not fall into the lower part of the gap 12.

Second option. The filtering cloth of the cartridge 8 is made on the basis of a high-precision mesh with the number of layers equal to seven in compliance with GOST 6613-86.

Mesh number in a row n, sizes of square cells dт.n 1.m=an 1 , the wire diameters dт.n=1.m=an=1 for CPF of fine purification for option 2 are presented in Table 2. In this case, the first layers 11 in

the direction of the gas flow have cells sizedbт.n=1.m=an=1 bгр.n=1.m=an=1, i.e., 0.14 0.2. Solid

particles with a maximum size dч bгр.n=1.m=an=1 exceed the diameter of the first two layers in

the directionof gas flow dч dт.n 1.m=an 1 ,i.e., 0.2 0.09mm. The metal wires of the meshes of

the first two layers 11 have a diameter dт.n 1.m=an 1 , less than half the maximum diameter dч/2of

the solid particles dт.n 1.m=an 1 dч /2, i.e.,0.09 0.1mm. Then the layer thickness of the first

two fibers Sт.n 1.m=an 1 2dт.n 1.m=an 1 , will be less than the maximum particle diameter 15,

Sт.n 1.m=an 1 dч , i.e., 0.18 0.2mm. Since the thickness Sт.n 1.m=an 1 does not exceed the

maximum diameter dч of the solid particle 15, i.e., Sт.n 1.m=an 1 <0.2 mm, it projects its center of gravity beyond the boundary 16 of this layer and, as a result, falls into the lower part of the gap 12.

Table 2

Mesh number in a row, square mesh sizes and wire diameters

for CPF fine purification according to option 2

63

Russian Journal of Building Construction and Architecture

The test results showed the following. For the first option, the presence of individual solid particles in the lower part of the gap 12 between the coarse and fine CPF without the formation of a continuous layer clogging the cells of the lower part of the coarse and fine CPF was noted.

For the second variant, the formation of a continuous layer with a height 23.0 mm, clogging the lower part of the gap 12 between coarse and fine CPCs and reducing their capacity.

Therefore the suggested ratio of the sizes of this methodological position:

This ratio prevents the accumulation of solid particles in the lower part of the gap between the coarse and fine CPF.

Conclusions

1.A calculation method has been developed that for the first time has allowed the representation of filtering cloth clogging as a change in a row of n sequentially arranged meshes in the course of a gas flow with square cells with the m-th standard size. In this case, each subsequent grid n in the direction of the gas flow has smaller initial and subsequent dimensions compared the previous mesh. In the suggested calculation method, conditions are implemented to prevent the deposition of solid particles in the lower part of the gap between the coarse and fine CPFs by including a number of ratios of the mesh sizes of the coarse and fine CPF meshes.

2.The expressions (2) and (3) were obtained to identify the value of the pressure loss on the filter cartridge and the mean integral value of the degree of clogging of the CPF depending on the value of the decrease in the free cross-section of all filter nets during clogging.

3.The formulas (4)––(7) are set forth for identifying the ratio of the mesh sizes of coarse and fine CPF grids allowing the prevention of the deposition of solid particles in the lower part of the gap between the coarse and fine CPF and maintaining their capacity.

References

1.Belousov V. V. Teoreticheskie osnovy protsessov gazoochistki [Theoretical foundations of gas purification processes]. Moscow, Metallurgiya Publ., 1988. 256 p.

2.Birger M. I., Val'dberg A. Yu., Myagkov B. I. Spravochnik po pyle- i zoloulavlivaniyu [Handbook of dust and ash collection]. Moscow, Energoatomizdat Publ., 1983. 312 p.

3.Gustov S. V. Istochniki vozniknoveniya i razmery vzveshennykh v prirodnom gaze tverdykh chastits [Sources of origin and sizes of particulate matter suspended in natural gas]. Nefegazovoe delo, 2011, no. 4, vol. 9, pp. 98––101.

64

4.Idel'chik I. E. Spravochnik po gidravlicheskim soprotivleniyam [Handbook of hydraulic resistance]. Moscow, Mashinostroenie Publ., 1975. 559 p.

5.Karyakin E. A. Promyshlennoe gazovoe oborudovanie: spravochnik [Industrial gas equipment: a directory]. Saratov, Gazovik Publ., 2013. 1125 p.

6.Kouzov P. A., Mal'gin A. D., Skryabin G. M. Ochistka gazov i vozdukha v khimicheskoi promyshlennosti [Purification of gases and air in the chemical industry]. Saint-Petersburg, Khimiya Publ., 1993. 320 p.

7.Mazus M. G., Mal'gin A. D., Morgulis M. L. Fil'try dlya ulavlivaniya promyshlennykh pylei [Filters for trapping industrial dust]. Moscow, Mashinostroenie Publ., 1985. 240 p.

8.Usachev A. P., Shuraits A. L., Rulev A. V., Salin D. V., Usuev Z. M. Ustroistvo po predotvrashcheniyu rasprostraneniya oblomkov za predely fil'truyushchego elementa prirodnogo gaza [Device for preventing the spread of debris beyond the filter element of natural gas]. Patent PF, 2016, no. 2016116727/05.

9.Shuraits A. L., Usachev A. P., Salin D. V., Khomutov A. O., Usuev Z. M. Ustroistvo dlya ochistki ot tverdykh chastits prirodnogo gaza vysokogo davleniya [A device for purification solid particles of natural gas of high pressure]. Patent PF, 2017, no. 2017111708.

10.Straus V. Promyshlennaya ochistka gazov: per. s angl. [Promyshlennaya ochistka gazov]. Moscow, Khimiya Publ, 1981. 616 p.

11.Usachev A. P. e.a. Teoreticheskie i prikladnye osnovy povysheniya effektivnosti i bezopasnosti ekspluatatsii ustanovok gruboi ochistki prirodnogo gaza ot tverdykh chastits v sistemakh gazoraspredeleniya: monografiya

[Theoretical and applied fundamentals of increasing the efficiency and safety of operation of coarse purification of natural gas from solid particles in gas distribution systems]. Saratov, Sarat. gos. tekhn. un-t Publ., 2013. 172 s.

12.Chugaev R. R. Gidravlika. Uchebnik dlya vuzov. Izdan-e 4-e dop. i pererab. [Hydraulics. Textbook for high schools]. Leningrad, Energoizdat. Leningr. otd-nie, 1982. 672 p.

13.Shur I. A. Gazoregulyatornye punkty i ustanovki [Gas control points and installations]. Leningrad, Nedra Publ., 1985. 288 p.

14.Guo B., Ghalambor A. Natural Gas Engineering Handbook. 2nd edition. Houston, Texas, Gulf Publishing Company, 2012. XX. 472 p.

15.Hutten I. M. Handbook of Nonwoven Filter Media 2nd Edition. Butterworth Heinemann, 2016. 660 p.

16.Mokhatab S., Poe W. A. Handbook of Natural Gas Transmission and Processing. Second Edition. Elsevier Inc., 2012. 802 p.

17.Sutherland K. Filters and Filtration Handbook. 5 edition. Elsevier Science, 2008. 523 p.

18.Thomas D., Charvet A., Bardin-Monnier N., Appert-Collin J-C. Aerosol Filtration. ISTE Press – Elsevier, 2016. 218 p.

19.Tien Ch. Principles of Filtration. Elsevier, Oxford, 2013. 360 p.

20.Trevor S. Filters and Filtration Handbook. 5 edition. Elsevier Butterworth Heinemann, 2016. 444 p.

21.Wang X. Economides M. Advanced Natural Gas Engineering. Gulf Publishing Company, 2013. 400 p.

65

Russian Journal of Building Construction and Architecture

DESIGNING AND CONSTRUCTION OF ROADS,SUBWAYS,

AIRFIELDS,BRIDGES AND TRANSPORT TUNNELS

DOI10.36622/VSTU.2021.49.1.006

UDC630*383

O. V. Ryabova 1, A. V. Skrypnikov 2, V. G. Kozlov 3, P. V. Tikhomirov 4

STUDYING A GEOGRAPHICAL ENVIRONMENT FOR ROAD DESIGN

Voronezh State Technical University 1

Russia, Voronezh

Voronezh State University of Engineering Technology 2

Russia, Voronezh

Voronezh State Agricultural University Named after the Emperor Peter the Great 3

Russia, Voronezh

Bryansk State Engineering and Technology University 4

Russia, Bryansk

1 D. Sc. in Engineering, Prof. of the Dept. of Road Construction and Maintenance, tel.: (473)236-18-89 2 D. Sc. in Engineering, Prof of the Dept. of Information Security, e-mail: skrypnikovvsafe@mail.ru

3 D. Sc. in Engineering, Prof. of the Dept. of Operation of Transport and Technological Machines, e-mail: vya-kozlov@yandex.ru

4 PhD in Engineering, Assoc. Prof. of the Dept. of Transport and Technological Machinery and Service, e-mail: vtichomirov@mail.ru

Statement of the problem. The state of theoretical studies in the field of engineering and landscape zoning is detailed.

Results. The analysis made it possible to outline the goals, objectives and the general methodology of research and modeling of organization and planning processes for the construction of departmental roads considering micro-landscapes, varying degrees of complexity of road construction, value of natural resources, species qualities of a road area as well as to optimize the design process of departmental highways.

Conclusions. The suggested comprehensive assessment of the natural and technogenic conditions for the construction of departmental highways is gaining economic, technical and environmental significance and can be employed as the basis for landscape design of departmental highways.

Keywords: road design, geographical environment, engineering and landscape zoning, landscape, road, integrated assessment.

Introduction. Viewing nature as a living, developing organism, a self-regulating system is an achievement of the past few decades. As this concept emerged, so did a new branch of science in geography, i.e., landscape science, which explores the structure, morphology, and dynamics of the development of the geographic environment. In this day and age, landscape science

© Ryabova О. V., Skrypnikov А. V., Коzlov V. G., Tikhomirov P. V., 2021

66

is becoming a scientific foundation for a comprehensive study of natural conditions for the purposes of agriculture and forestry, urban planning, balneology, land reclamation and other types of economic activity as well as serves as a basis for design solutions.

The accomplishments of physicists and geographers in natural-historical zoning of Russia were a starting point for road-climatic zoning. Later on, some additions were introduced considering the climatic indicators of the previously identified road zones. The criteria for zoning in five road-climatic zones are based on the “balance of heat and moisture considering the general features of road construction” [8].

Road-climatic zoning has become the foundation for a comprehensive evaluation of the geographical environment for the design of subgrade and road pavements, which allows the design principles to be standardized.

Along with the positive aspects of a comprehensive study of natural conditions, the existing roadclimaticzoningdoesnot completelycomplywiththedesignrequirements.Itshouldbenoted:

1.A vector, formal approach of designers to the evaluation of natural conditions and the application of standards for the design of subgrade and road pavements;

2.Lack of guidelines for improving the system of comprehensive evaluation of the geographic environment of smaller territorial units (subzones, regions, landscapes, etc.), thus ruling out the possibility of employing these data for tracing departmental highways;

3.Zoning is largely based on the analysis of climate and soil and subgrade, while such components of the geographic environment as topography and geological structure remain neglected. In the recent years, there has been a number of studies by domestic road scientists [3, 6, 8, 10, 12, 15, 17] where the need to clarify and detail the existing system of roadclimatic zoning is identified.

1.Theoretical provisions and methods of road zoning are suggested in the studies by V. M. Sidenko, V. G. Kozlov, K. A. Yakovlev, etc. [8, 17]. So far, this has been the first attempt to theoretically substantiate the principles of regional evaluation of natural conditions. The authors argue that the key method for studying the geographic environment is road zoning, i.e., “a method of combining homogeneous territories by any criteria that have a major impact on the design, construction or operation of departmental highways” and they divide zoning into “physical” and “engineering” [4]. Physical zoning relies on the principle of allocating territories according to “geographic complexes”, engineering ones –– according to road criteria.

The major geographic complexes are classed by the authors as climate, relief, geology, soils, ground and surface waters, vegetation whose role depends on the purposes of region-

67

Russian Journal of Building Construction and Architecture

alization. The characteristics of geocomplexes that impact the strength and durability of a departmental road or the construction process are referred to as road criteria.

For design purposes, V. M. Sidenko [18] suggests that the calculated moisture content or strength of soil foundations, the maximum amount of heaving, etc. is taken as a criterion. For construction purposes this is the timing of the start and end of road construction works, optimal in terms of climatic conditions, etc. zoning criterion for the operation of departmental highways –– wind direction, “snowfall”, frequency of snow drifts and other characteristics.

The major theoretical provisions of road zoning rely on the following scheme:

1.The foundation of regionalization is landscape science, i.e., study of a landscape;

2.Differentiation of the geographic environment should be based on the patterns of zonal and azonal changes;

3.A zone, subzone, district, site is set forth as a taxonometric system of zoning.

The first two units are assigned to the highest rank, the subsequent ones to the lowest. The zoning technique, according to V.M.Sidenko, is carried out in the following sequence:

1.The system of geocomplexes is substantiated, their impact is identified depending on the accepted road criterion;

2.The change of geocomplexes in time and space is considered and their calculated value is identified;

3.The regularity of the change in the road criterion is established depending on the change in geocomplexes, which allows for road zoning.

According to V. M. Sidenko, the major task of road zoning of the territory is the differentiation of micro-districts into districts. The theoretical provisions and the method of road zoning developed by the author [18] constituted the basis for zoning. The given detailed presentation in the study by V. M. Sidenko had two goals: to show the level of theoretical development of the issue of road zoning at the current stage and to make a number of critical remarks on the issue.

We believe that the major disadvantages of the work are the following:

1.The theoretical provisions of road zoning are developed merely as a scheme, there is no clarity in how the material is presented. E.g., the author argues that “the higher regions should be the foundation for general road zoning, natural for design, construction and operation”, and here he goes on to say that “there can be no single zoning, suburban for all cases”;

2.The terms and concepts used by the author in the work (e.g., “a geocomplex”) have not been sufficiently explained;

3.“Road criteria” are presented different for design, construction, operation, while in the design of departmental highways, they should be considered in combination;

68

4. Road zoning is not clearly defined. In our opinion, it would be more correct to define it as in the collective monograph by A. A. Kamusin, V. V. Nikitin, I. N. Zhuravlev, V. G. Kozlov, V. N. Logachev, I. I. Bukhtoyarov [7]. What sets this work apart is a clear statement of the problem, a methodology for identifying the quantitative characteristics of the components of the geographic environment, such as climate, ground hydrological and permafrost features. The zoning is based on factors influencing the stability of road structures: the type of soil in the seasonally thawing layer and its moisture content, the nature of the distribution of permafrost soils and their temperature, the thickness of the seasonal thawing layer. The studies made it possible to clarify the boundaries of the zone and divide it into road areas using which the principles of design and construction of the roadbed in 1 road-climatic zone were developed.

Studies on the road-climatic zoning of the foothills were performed by M. D. Krutsik, V. K. Kuryanov, E. V. Kondrashova, etc. [5, 8––9, 11, 13––14]. According to the characteristics of the climate, vegetation, and soils, the authors identified three road areas for which rational types of road pavements were identified, and the duration of the construction season was established. The work sets out to improve design and construction methods. In order to differentiate the territory, the authors utilized the method of overlaying maps of the same scale reflecting the spatial distribution of the major components of the geographic environment: climate, relief, soil. The issues of the methodology of road zoning are covered in [16, 21, 23]. According to their authors, zoning is “a set of practical techniques and methods for dividing a territory” in compliance with the tasks of examining natural characteristics. The following examples are proposed for designing non-rigid pavements:

1.The overlay method widely used by V. M. Sidenko, M. D. Krutsi, etc.;

2.Leading factor method;

3.The method of conjugate regional state of structural elements of road pavements.

The zoning relies on identifying natural factors that directly impact the choice of the type, design and strength indicators of road pavements. This data allows one to:

1.Identify the boundaries of the road and climatic zones for which the strength of the soil has a different value;

2.Establish the degree of provision of construction with road-building materials;

3.Determine Identify soil types;

4.Identify the characteristics of the area and the degree of moisture.

The objectivity of the division of districts into groups of complexity was tested by means of the method of mathematical statistics. The research results are of some interest for road construction planning and set out to improve survey work.

69

Russian Journal of Building Construction and Architecture

An assessment of natural conditions in the central part of the Russian Plain for the purposes of road construction is presented in the work by N. V. Isheeva [2, 17]. For the engineering evaluation, the “price increase factors” of the cost of 1 km of road construction were employed. The studies by physicists-geographers are of indisputable interest and make a considerable contribution to the development of the theory and methodology of road zoning. However, in our opinion, such work should be performed in close contact with road engineers. This path is considered the most viable one by the physicists-geographers themselves [6, 19].

In overseas practice of road design, there is also a tendency towards an integrated accounting of physical and geographical conditions [6, 19].

The Interdepartmental Authority for Road Research of the USA presented the report “The Dependence of the Design of Highways on Local Physical and Geographical Conditions”. The report summarizes information about local road-building materials, the load-bearing capacity of soils and their changes under the influence of moisture based on the abyss resistance, the area of the United States is divided into 97 physical-geographical regions [19––22].

While designing the road network in Mexico [22], special application maps were developed for evaluating the road construction conditions reflecting the population density, the nature of the relief, the degree of economic use of the territory and development prospects, the density and configuration of the existing road network. Apart from comprehensive research, the study and mapping of the patterns of distribution of individual components of the geographic environment for road design purposes is being performed.

The issues of the methodology for evaluating the relief are covered in the study by N. A. Sitsenko [8]. An objective characteristic is presented in the form of graphical curves of the percentage of slopes. Graphs allow the slopes of the terrain to be determined and can be used in order to substantiate the geometrical characteristics and regionalization of territories based on relief conditions.

In Finland, studies have performed [22] into the effect of relief on the geometry of roads. The classification criteria for the regionalization of the territory were the complexity of construction.

2. Comprehensive study of the geographic environment for tracing highways. The issue of exploring natural conditions and human economic activity as factors central to the directions and location of the road route are of particular importance. The more complex the natural and man-made situation in the survey area is, the more information a road engineer must process for solving road tracing problems.

Road routing is the most relevant and daunting stage of road design. The engineer must have sufficient knowledge of the dynamics of a car as well as of natural conditions and the

70