What are topographic maps and plans. Technological map of the lesson on the topic "how to make topographic plans and maps." Topographic map elements

According to the content and purpose, geographic maps are divided into special and general geographic.

Special maps show contours and special load (mineral map, physical map peace, political map, map of flora and fauna, economic map).

General geographic maps show the situation and relief.

General geographical maps smaller than 1: 1000000 are called general maps.

General geographic maps at a scale of 1: 1,000,000 and larger are called topographic maps.

Topographic maps, plans and differences between them

Topographic maps are created in the zonal conformal transverse cylindrical projection of K.F. Gauss-Kruger, calculated on the reference ellipsoid F.N. Krasovsky in the state coordinate system of 1942 in the 6° zone. And plans on a scale of 1: 5,000 and larger in the 3 ° zone. The heights of the points are determined in the absolute Baltic system of heights from zero of the Kronstadt footstock.

MAP - built in a cartographic projection, reduced and generalized image on the plane of the entire Earth or part of it, taking into account the curvature of the Earth.

Mapping begins with the construction of a cartographic grid, inside which the situation and relief are depicted with conventional signs.

A cartographic grid is a network of parallels and meridians.

PLAN - a reduced and similar image of the projection of a small area of area on a plane without taking into account the curvature of the Earth.

Drawing up a plan begins with the construction of a coordinate grid, within which, according to the results of a field survey, the situation and relief are depicted with conventional signs.

Coordinate grid - mutually perpendicular lines on the map, forming squares, the sides of which are parallel to the X and Y axes (i.e. the axial meridian and the equator.)

Plans are divided into contour (situational) and topographic.

Contour plans - plans that show only the contours of the situation of the area without depicting the relief.

Topographic - plans that depict both the situation of the terrain and the relief.

Differences between map and plan:

1. The plan is based on a coordinate grid.

Map - based on a cartographic grid.

2. Plan - an image of a small area of the Earth without taking into account the curvature of the Earth.

A map is a depiction of the entire Earth or a large area of the Earth, taking into account the curvature of the Earth.

3. There is only a rectangular coordinate system on the plan.

There are two coordinate systems on the map: rectangular and geographic.

2.1. Topographic map elements

Topographic map - a detailed large-scale general geographic map that reflects the location and properties of the main natural and socio-economic objects, making it possible to determine their planned and altitude position.

Topographic maps are created mainly on the basis of:

processing of aerial photographs of the territory;
by direct measurements and surveys of terrain objects;
cartographic methods with already available plans and maps of large scales.

Like any other geographical map, a topographic map is a reduced, generalized and figurative-sign image of the area. It is created according to certain mathematical laws. These laws minimize the distortions that inevitably occur when the surface of the earth's ellipsoid is transferred to a plane, and, at the same time, ensure its maximum accuracy. The study and compilation of maps require an analytical approach, the division of maps into its constituent elements, the ability to understand the meaning, meaning and function of each element, and to see the connection between them.

Map elements (components) include:

cartographic image;
mathematical basis;
legend
auxiliary equipment;
Additional information.

The main element of any geographical map is a cartographic image - a set of information about natural or socio-economic objects and phenomena, their location, properties, connections, development, etc. Topographic maps depict water bodies, relief, vegetation, soils, settlements, means of communication and means of communication, some objects of industry, agriculture, culture, etc.
Mathematical basis topographic map- a set of elements that determine the mathematical relationship between the real surface of the Earth and the flat cartographic image. It reflects the geometric laws of map construction and the geometric properties of the image, provides the ability to measure coordinates, plot objects by coordinates, fairly accurate cartometric determinations of lengths, areas, volumes, angles, etc. Due to this, a map is sometimes called a graph-mathematical model of the world.

The mathematical basis is:

map projection;
coordinate grids (geographical, rectangular and others);
scale;
geodetic substantiation (strong points);
layout, i.e. placement of all elements of the map within its frame.

kata scale can have three types: numerical, graphic (linear) and explanatory label (named scale). The scale of the map determines the degree of detail with which a cartographic image can be plotted. Map scales will be discussed in more detail in Topic 5.
Map grid represents the image of the degree grid of the Earth on the map. The type of grid depends on the projection in which the map is drawn. On topographic maps of scales 1:1,000,000 and 1:500,000, meridians look like straight lines converging at a certain point, and parallels look like arcs of eccentric circles. On topographic maps of a larger scale, only two parallels and two meridians (frame) are applied, limiting the cartographic image. Instead of a cartographic grid, a coordinate (kilometer) grid is applied to large-scale topographic maps, which has a mathematical relationship with the degree grid of the Earth.
card frame name one or more lines bounding the map.
To strong points include: astronomical points, triangulation points, polygonometry points and leveling marks. Control points serve as a geodetic basis for surveying and compiling topographic maps.

2.2. Topographic map properties

Topographic maps have the following properties: visibility, measurability, reliability, modernity, geographical correspondence, geometric accuracy, content completeness.
Among the properties of a topographic map, one should highlight visibility and measurability . The visibility of the map provides a visual perception of the image of the earth's surface or its individual sections, their characteristic features and features. Measurability allows you to use the map to obtain quantitative characteristics of the objects depicted on it by measurements.

Visibility and measurability are provided by:

a mathematically defined relationship between multidimensional objects environment and their flat cartographic representation. This connection is conveyed using a map projection;

the degree of reduction in the size of the depicted objects, which depends on the scale;

highlighting typical terrain features by means of cartographic generalization;

the use of cartographic (topographic) conventional signs to depict the earth's surface.

To ensure a high degree of measurability, the map must have sufficient geometric accuracy for specific purposes, which means the correspondence of the location, shape and size of objects on the map and in reality. The smaller the depicted area of the earth's surface while maintaining the size of the map, the higher its geometric accuracy.
The card must be credible, i.e., the information that makes up its content on a certain date must be correct, must also be contemporary, correspond to the current state of the objects depicted on it.
An important property of a topographic map is completeness content, which includes the volume of information contained in it, their versatility.

2.3. Classification of topographic maps by scale

All domestic topographic maps, depending on their scale, are conditionally divided into three groups:

small scale maps (scales from 1:200,000 to 1:1,000,000), as a rule, are used for general study of the area in the development of projects and plans for the development of the national economy; for preliminary design of large engineering structures; as well as for taking into account the natural resources of the surface of the earth and water spaces.
Medium scale maps (1:25,000, 1:50,000 and 1:100,000) are intermediate between small-scale and large-scale. The high accuracy with which all terrain objects are depicted on maps of a given scale makes it possible to widely use them for various purposes: in the national economy in the construction of various structures; for making calculations; for geological prospecting, land management, etc.
large scale cards (1:5,000 and 1:10,000) are widely used in industry and public utilities; when conducting detailed geological exploration of mineral deposits; when designing transport hubs and structures. Large-scale maps play an important role in military affairs.

2.4. Topographic plan

Topographic plan - a large-scale drawing depicting in conventional symbols on a plane (on a scale of 1:10,000 and larger) a small area of the earth's surface, built without taking into account the curvature of the level surface and maintaining a constant scale at any point and in all directions. A topographic plan has all the properties of a topographic map and is its special case.

2.5. Topographic map projections

When depicting large areas of the earth's surface, the projection is made on the level surface of the Earth, in relation to which the plumb lines are normals.

map projection - method of imaging on a surface plane the globe when making maps.

It is impossible to develop a spherical surface on a plane without folds and breaks. For this reason, distortions of lengths, angles and areas are inevitable on maps. Only in some projections the equality of angles is preserved, but because of this, the lengths and areas are significantly distorted, or the equality of areas is preserved, but the angles and lengths are significantly distorted.

Projections of topographic maps at a scale of 1:500,000 and larger

Most countries of the world, including Ukraine, use conformal (conformal) projections to compile topographic maps, preserving the equality of angles between the directions on the map and on the ground. The Swiss, German and Russian mathematician Leonhard Euler in 1777 developed the theory of conformal image of a ball on a plane, and the famous German mathematician Johann Carl Friedrich Gauss in 1822 substantiated the general theory of conformal image and used conformal flat rectangular coordinates when processing triangulation (method of creating a network of reference geodetic points). Gauss applied a double transition: from an ellipsoid to a ball, and then from a ball to a plane. The German geodesist Johannes Heinrich Louis Krüger developed a method for solving conditional equations arising in triangulation and a mathematical apparatus for the conformal projection of an ellipsoid onto a plane, called the Gauss-Krüger projection.
In 1927, the well-known Russian geodesist, Professor Nikolai Georgievich Kell, was the first in the USSR to use the Gaussian coordinate system in Kuzbass, and on his initiative, since 1928, this system was adopted as a single system for the USSR. To calculate the coordinates of Gauss in the USSR, the formulas of Professor Feodosy Nikolaevich Krasovsky were used, which are more accurate and more convenient than Kruger's formulas. Therefore, in the USSR there was no reason to give the Gaussian projection the name "Gauss-Kruger".
Geometric entity This projection can be represented as follows. The entire terrestrial ellipsoid is divided into zones and maps are made for each zone separately. At the same time, the dimensions of the zones are set so that each of them can be deployed into a plane, that is, depicted on a map, with virtually no noticeable distortion.
To obtain a cartographic grid and draw up a map in the Gaussian projection, the surface of the earth's ellipsoid is divided along the meridians into 60 zones of 6 ° each (Fig. 2.1).

Rice. 2.1. The division of the Earth's surface into six-degree zones

To imagine how the image of zones is obtained on a plane, imagine a cylinder that touches the axial meridian of one of the zones of the globe (Fig. 2.2).

Rice. 2.2. Zone projection onto a cylinder tangent to the Earth's ellipsoid along the axial meridian

According to the laws of mathematics, we project the zone onto the lateral surface of the cylinder so that the property of the equiangularity of the image is preserved (the equality of all angles on the surface of the cylinder to their magnitude on the globe). Then we project all other zones, one next to the other, onto the side surface of the cylinder.

Rice. 2.3. Image of zones of the earth's ellipsoid

Further cutting the cylinder along the generatrix AA1 or BB1 and turning its side surface into a plane, we obtain an image of the earth's surface on a plane in the form of separate zones (Fig. 2.3).
The axial meridian and the equator of each zone are depicted as straight lines perpendicular to each other. All axial meridians of the zones are depicted without length distortion and maintain the scale throughout their entire length. The remaining meridians in each zone are depicted in the projection by curved lines, therefore they are longer than the axial meridian, i.e. distorted. All parallels are also shown as curved lines with some distortion. Line length distortions increase with distance from the central meridian to the east or west and become greatest at the edges of the zone, reaching a value of the order of 1/1000 of the line length measured on the map. For example, if along the axial meridian, where there is no distortion, the scale is 500 m in 1 cm, then at the edge of the zone it will be 499.5 m in 1 cm.
It follows that topographic maps are distorted and have a variable scale. However, these distortions when measured on a map are very small, and therefore it is believed that the scale of any topographic map for all its sections is constant.
For surveys at a scale of 1:25,000 and larger, the use of 3 degree and even narrower zones is allowed. The overlap of zones is taken 30" to the east and 7", 5 to the west of the axial meridian.

The main properties of the Gaussian projection:

the axial meridian is depicted without distortion;

the projection of the axial meridian and the projection of the equator are straight lines perpendicular to each other;

the remaining meridians and parallels are depicted by complex curved lines;

in the projection, the similarity of small figures is preserved;

in projection, horizontal angles and directions are preserved in the image and terrain.

Projection of a topographic map at a scale of 1:1,000,000

Projection of a topographic map at a scale of 1:1,000,000 - modified polyconic projection, accepted as international. Its main characteristics are: the projection of the earth's surface covered by a map sheet is carried out on a separate plane; parallels are represented by arcs of circles, and meridians by straight lines.
To create topographic maps of the USA and the countries of the North Atlantic Alliance, Universal Transverse Mercator, or UTM. In its final form, the UTM system uses 60 zones, each 6 degrees longitude. Each zone is located from 80º S. up to 84º N The reason for the asymmetry is that 80º S. passes very well in the southern ocean, southern South America, Africa and Australia, but it is necessary to climb to 84º N to reach the north of Greenland. Zones are counted starting from 180º, with increasing numbers to the west. Together, these zones cover almost the entire planet, excluding only the Arctic Ocean and North and Central Antarctica in the south.
The UTM system does not use a "standard" based on the transverse Mercator projection - the tangent. Instead, it is used secant, which has two section lines located approximately 180 kilometers on either side of the central meridian. Map zones in the UTM projection differ from each other not only in the positions of their central meridians and distortion lines, but also in the earth model they use. The official definition of the UTM system defines five other spheroids for use in various zones. All UTM zones in the United States are based on the Clarke 1866 spheroid.

Questions and tasks for self-control

Give definitions: "Topography", "Geodesy", "Topographic map".
What are the sciences of topography? Explain this relationship with examples.
How are topographic maps created?
What is the purpose of topographic maps?
What is the difference between a topographic plan and a topographic map?
What are the elements of a map?
Give a description of each element of the topographic map.
What are the parallels and meridians on topographic maps?
What elements determine the mathematical basis of a topographic map? Give a brief description of each element.
What are the properties of topographic maps? Give a brief description of each property.
On what surface are images of large areas of the Earth projected?
Define a map projection.
What distortions can be formed when a spherical surface is deployed on a plane?
What projections are used by most countries of the world to compile topographic maps?
What is the geometric essence of the construction of the Gaussian projection?
Show on the drawing how a six-degree zone is projected from the earth's ellipsoid to a cylinder.
How are the meridians, parallels, and equator drawn in the six-degree Gaussian zone?
How does the nature of distortion change in the six-degree Gaussian zone?
Can the scale of a topographic map be considered constant?
In what projection is the topographic map made at a scale of 1:1,000,000?
Which map projection used to create topographic maps in the US, and how is it different from a Gaussian projection?

Federal Agency for Railway Transport Ural State University of Railway Transport Department "Bridges and Transport Tunnels"

B. G. Chernyavsky

SOLUTION OF GEODETIC AND ENGINEERING PROBLEMS

ON TOPOGRAPHIC MAPS AND PLANS

Methodical instructions on engineering geodesy for students of construction specialties

Yekaterinburg Publishing House UrGUPS

Chernyavsky, B. G.

Ch-49 Solution of geodetic and engineering problems on topographic maps and plans: method. instructions / B. G. Chernyavsky. - Yekaterinburg: Publishing House of UrGUPS, 2011. - 44 p.

The guidelines are intended for 1st year students of all forms of education in the direction of preparation 270800 - "Construction". Compiled in accordance with the curriculum and the program for the discipline "Engineering Geodesy", can be used both in the classroom and in independent work students.

Examples of calculation and graphic design works, the volume of the task is indicated, control questions are given.

Reviewer: F.E. Reznitsky, Associate Professor, Ph.D. tech. Sciences

Educational edition

Editor S.I. Semukhin

Signed for publication on November 22, 2011. Format 60x84/16 Offset paper. Conv. oven l. 2.6.

Circulation 300 copies. Order No. 165.

Publishing house UrGUPS 620034, Yekaterinburg, st. Kolmogorova, 66

Introduction ………………………………………………………………….. 4

1. Scales of topographic maps and plans, measurement of line lengths on maps and plans. Symbols for topographic maps and plans ………………………………………………………………………...5

2. Definition of geodetic and rectangular coordinates dots,

orientation angles of lines according to topographic maps and plans ……………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………

3. The study of the terrain on the topographic map and plan. Drawing contour lines on a digital elevation model. Determining point elevations ……………………………………………….19

4. Solving engineering problems using topographic maps

and plans ……………………………………………........................... ..25

5. Geodetic preparation of the project of a building, structure for transferring it from a topographic plan to the area……….……32

6. Measurement of the areas of the earth's surface using maps

and plans using a polar planimeter………………...….……...40

Bibliographic list……………………………………………...44

Introduction

Topographic maps and plans are the basis for drafting various linear structures (railways and roads, power lines, heating mains, etc.), industrial and civil buildings, engineering structures (bridges, overpasses, tunnels), as well as for the land cadastre.

As a result of the work on six topics, students should be able to solve geodetic and engineering problems according to maps and plans, perform geodetic preparation of the project, including drawing up a layout drawing to perform work on determining the design of a building, structure on the ground, and also determine the areas of the earth's surface.

1. Scales of topographic maps and plans. Measurement of line lengths on maps and plans.

Symbols for topographic maps and plans

1. Familiarize yourself with topographic maps and plans, their scales and symbols.

2. Using a measuring compass and a linear scale, measure the lengths of lines on a map at a scale of 1:10,000.

3. Paste the given schedule into the notebook transverse scale with a base of 2 cm and digitize it for a scale of 1: 2000. Put a few lines of a given length on the chart.

4. Draw with a base of 5 cm a graph of the transverse scale for the plan at a scale of 1:2000. Plot several lines of a given length on the graph.

5. Draw a table of symbols.

6. Prepare a report on the work performed.

1.1. General information about maps and plans, their scales

A map is a reduced image on a plane of significant areas of the earth's surface, taking into account the curvature of the Earth. The map is inherently distorted, since the ellipsoidal surface onto which the earth's surface is projected cannot be turned into a plane without distortion. Map projections are used to reduce and account for these distortions.

Maps of scales 1:100,000, 1:50,000, 1:25,000 and 1:10,000 are called

topographic. In Russia, topographic maps are compiled in the Gaussian projection. On maps of certain scales, elements of the terrain are depicted with approximately the same accuracy and detail.

A plan is a reduced and similar image on a plane of small areas of terrain (up to 320 km2), within which the curvature of the Earth can be neglected. Topographic plans are created to scale

1:5000, 1:2000, 1:1000 and 1:500.

The points of the earth's surface are projected onto a mathematical surface - an ellipsoid or a plane along the normals, i.e. orthogonally (Fig. 1).

Rice. 1. Projection of points on the earth's surface onto a plane:

D is the slope distance; ν is the angle of inclination of the line; d is the horizontal distance; P - horizontal plane

The scale of the map, plan is the degree of reduction of horizontal projections - the laying of terrain lines (10 - 20) when depicted on a plane or, in other words, the ratio of the depicted line (1 ′ -2 ′) on the map or plan to its horizontal laying on the ground:

where M is the scale denominator.

For example, a scale of 1: 2000 means: one centimeter of the length of the line on the plan corresponds to 2000 centimeters on the ground in horizontal alignment. Recording the scale as a fraction with a numerator equal to one is called a numerical scale.

On topographic maps, for example, at a scale of 1:10,000, there is also an entry in the form of a phrase: “100 meters in 1 centimeter” - a named scale.

On maps and plans under the south side of the sheet indicate the numerical and named scales. In addition, the map shows a linear scale in the form of a scale, the divisions of which are signed (digitized) in accordance with the numerical scale.

The accuracy of the scale of the plan, map is the horizontal distance on the ground, corresponding to 0.1 mm on the plan, map.

1.2. Guidelines for the implementation of the work “Scales of topographic maps and plans. Measurement of line lengths on maps and plans"

Graphic constructions on paper when creating plans or maps are carried out with an accuracy of 0.1 mm. To obtain such accuracy in laying or measuring line lengths, transverse scale graphs are used, engraved on a special metal scale ruler or on the ruler of a geodetic protractor.

To build such a graph on a straight line, the segment AB is laid several times, called the base of the scale (Fig. 2). Usually, the segment AB \u003d 2 cm. Then, from this line, 10 more lines parallel to the base are drawn upwards at the same distance.

Rice. 2. Graph of the cross scale

From the ends of the segments of the base, perpendiculars are restored. Then the lower and upper bases of the AB scale are divided into 10 equal parts and oblique lines are drawn through the division points as shown in Fig. 2.

Depending on the scale of the plan or map, a special digitization of the graph is performed (see Fig. 2, digitization for a scale of 1:2000), but in any case, “zero” is set at point B. The resulting plot is called a cross-scale plot.

The AC line is a linear scale used to measure lines on maps. The smallest division ef of the transverse scale plot is 0.01 AB bases. A graph with a base AB \u003d 2 cm is called normal, since the segment ef is 0.2 mm (ef \u003d 0.01 AB \u003d 0.01 2 cm \u003d 0.2 mm) and it can be divided in half. Therefore, the accuracy of graphic constructions on paper is assumed to be 0.1 mm.

The accuracy of measuring or laying down the lengths of lines on maps, plans is determined by the formula:

t = 0.1 mm M, where M is the denominator of the map or plan scale.

For determining horizontal the lines on the plan (map) take this line into the solution of the measuring compass and transfer it to the bottom line of the graph so that the right needle of the meter is aligned with one of the perpendiculars, and the left one hits the base of the scale AB. Moving the gauge up so that the right needle remains perpendicular, note the position when the left needle touches the inclined line. In this case, both needles should be on the same horizontal line. The desired length will be obtained by summing the whole bases of the scale that fit between the needles, their tenths and hundredths.

On fig. 2 line length d mn, taken from the scale plan 1: 2000, has a length

d mn \u003d 80 m + 5 x 4 m + 7 x 0.4 m \u003d 102.8 m.

Measurement accuracy 0.2 m.

The graph of the transverse scale with a base of 2 cm is plotted on the ruler of a geodetic protractor and digitized for a scale of 1:500. On a special scale bar there are four graphs of a transverse scale with a base of 1, 2, 4 and 5 cm. Using such a ruler, the measurement or laying down of line lengths is performed without calculations, since all divisions of the graphs are multiples of 0.1 m; 1m; 10 m; 100 m line length on the ground for all standard scales.

1.3. Guidelines for the implementation of the work "Conventional signs for topographic plans." General information

Objects of the situation and terrain are depicted on topographic plans by conventional symbols, which are given in special tables of the book "Conventional symbols for topographic scale plans

1:5000, 1:2000, 1:1000 and 1:500". - M. Nedra, 1989.

Conventional signs are divided into areal (contour), linear and off-scale.

Areal (contour) conventional signs depict terrain objects that have contour dimensions, the area of \u200b\u200bwhich is expressed on the scale of this plan. A conventional sign or an explanatory inscription is placed inside the contour, revealing the content of the object. The boundary (contour) of terrain objects can be a dotted line or a solid line.

Linear symbols are used to represent linear objects. In the scale of the plan for such objects, only the length is expressed. These are roads, power lines and communications, pipelines, etc.

Out-of-scale conventional signs depict terrain objects that are not expressed on the scale of the plan. This is how geodetic points, structures at railways and roads, poles of power lines and communications, wells, etc. are depicted. Extra-scale include explanatory conventional signs: inscriptions, numbers, signs of vegetation types. Most of the inscriptions on the plans are placed horizontally - parallel to the south side of the frame.

Paints are used to finish the plans. The black color is used to show the elements of the situation and the inscriptions. Pink and yellow (orange) colors are used to show paved surfaces (surfaces of roads, sidewalks, etc.). Areas occupied by forests and shrubs are painted in green, hydrography is shown in blue, relief is shown in brown.

Task for performing graphic work

Having got acquainted in the reading room of the university with the book "Conventional signs for topographic plans of scales 1:5000, 1:2000, 1:1000 and 1:500", students study and draw in pencil or, if desired, in color (ink, gel) on on an A4 sheet, the following symbols for plans at a scale of 1:2000, which will be used when performing graphic work on compiling a topographic plan (signs 5.1; 12; 13.2; 16.1; 115.5; 136; 155; 174.1; 193.1; 310; 314.2; 330.1; 366.1; 367.2; 368; 395.1; 401; 417; 475). Symbols are drawn according to size. The dimensions themselves are also indicated on the drawing.

The sizes of letters and numbers in conventional signs are taken according to Table. 116-118 of the book (signs 493, 494, 495). The rules for drawing conventional signs are given in the explanations on p. 121 - 254.

For the correct placement of the signature of the work, students study the sample design of plans according to Table. 87 book inserts. The height of lowercase letters in the signature of this and all subsequent graphic works is taken equal to 2 mm, capital letters and numbers - 3 mm.

1.4. The work report is:

– drawn cross-scale graph with a base of 5 cm for a scale of 1:2000;

– table of symbols;

– answers to control questions.

test questions

1. What is the scale of a map and plan?

2. How is the scale shown on maps and plans?

3. What is called the accuracy of the scale of the map, plan?

4. How to determine the accuracy of measuring the lengths of lines on a map or plan?

5. What is the sequence of work when measuring the length of a line on a map using measuring compass and linear scale?

6. How is a cross-sectional graph plotted?

7. What is the sequence of work when measuring the length of a line on a map (plan) using a meter and a scale bar?

8. What is the sequence of work when postponing the length of a line on paper using compass and scale ruler?

9. What are the features of transverse scale plots with a base of 2 cm and 5 cm?

10. Give examples of areal, linear and off-scale symbols.

Carries out a complex of works on the preparation of engineering and topographic plans of all scales. The area of work is Moscow and all the Moscow region. Contact us - and you will not regret!

Drawing up a topographic plan is an integral part of any construction or improvement on a land plot. Of course, you can put a barn on your site without it. Arrange paths and plant trees too. However, it is undesirable, and often impossible, to start more complex and voluminous work without a topoplan. In this article, we will talk specifically about the document itself, as such - why it is needed, how it looks, etc.

After reading for yourself, you need to understand whether you really need a topoplan, and if so, what it is.

What is a topographic plan of a land plot?

We will not load you with the official definition, which is more needed for professionals (although they already know the essence). The main thing is to understand the essence of this plan and its difference from others (for example, a floor plan, etc.). To compose it, you need to spend. So, a topoplan is a drawing of the elements of a situation, terrain and other objects with their metric and technical specifications, made in approved conventional signs. The main feature is its height component. That is, in any place of the topographic plan, you can determine the height of the object depicted there. In addition to the height, it is possible to measure the coordinates and linear dimensions of objects on the topoplan, taking into account, of course. All these data can be obtained both from a paper copy and from a digital one. Usually both options are prepared. Therefore, the topographic plan, in addition to a visual representation of the terrain, is the starting point for design and modeling.

Another topoplan is often called geo-underlying and vice versa . In fact, these are two identical concepts with minor reservations. A geo-underlay can contain several topographic plans. That is, this is a collective concept for the entire territory of the object under study. Underground utilities must be indicated on the geo-base, in contrast to the topographic plan (the subway is indicated there if necessary). But despite the subtleties, these concepts can still be equated.

Who draws up and what is used to make a topographic plan?

Topographic plans are made by geodetic engineers. However, now you can’t just graduate from a university, get a diploma, buy equipment and start surveying. It is also necessary to work as part of an organization that has membership in the relevant SRO (self-regulating organization). This has become mandatory since 2009 and is designed to increase the responsibility and preparedness of surveying engineers. Our company has all the necessary permits for engineering and survey activities.

We use advanced equipment () for successful work in any conditions and directions of geodetic surveys. In particular, electronic roulettes, etc. All devices have been certified and have.

Processing of all materials and measurements is carried out on specialized licensed software.

Why do you need a topographic plan?

Why is a topographic plan needed by an ordinary owner of a land plot, or a large construction organization? In fact, this document is a pre-design for any construction. A topographic plan of a land plot is needed in the following cases:

We have written a full article on this topic - if you are interested, click.

Documents required for ordering a topographic plan

If the Customer is an individual, it is enough to simply indicate the location of the object (address or cadastral number of the site) and verbally explain the purpose of the work. For legal entities it won't be enough. Still, interaction by a legal entity implies the mandatory drawing up of an agreement, an act of acceptance and receipt of the following documents from the Customer:

Terms of reference for the production of topographic and geodetic works
-Situational plan of the object
- Available data on previously produced topographic works, or other documents containing cartographic data about the object

After receiving all the data, our specialists will immediately begin work.

What does a topographic plan look like?

A topographic plan can be either a paper document or a DTM (digital terrain model). At this stage in the development of technologies and interactions, a paper version is still needed.

An example of a topographic plan for an ordinary private land plot shown on the right⇒.

As for the regulatory documents on the methods of conducting topographic surveys and designing topographic plans, quite “ancient” SNIPs and GOSTs are also used:

All of these documents can be downloaded by clicking on the links.

Topographic plan accuracy

The above regulatory documents detail the tolerances for determining the planned and height coordinates of the position of objects on topographic maps. But in order not to delve into a large amount of technical and often unnecessary information, we will present the main accuracy parameters for topographic plans at a scale of 1:500 (as the most popular ones).

Topoplan accuracy is not a single and indestructible value. One cannot simply say that the angle of the fence is determined with an accuracy of, for example, 0.2m. You need to specify what. And here are the following values.

- the average error of the planned position of clear contours of objects should not exceed 0.25 m (undeveloped area) and 0.35 m (built-up area) from the nearest points of the geodetic base (GGS). That is, this is not an absolute value - it consists of errors in the shooting process and errors in the starting points. But in fact it is an absolute error in determining the point of the terrain. After all, the starting points are considered infallible when leveling topographic moves.

– the maximum error in the relative position of points of clear contours, spaced from each other at a distance of up to 50 meters, should not exceed 0.2 m. This is a control of the relative error in the location of terrain points.

- the average error of the planned position of underground utilities (detected by a pipe-cable detector) should not exceed 0.35 m from the GGS points.

Laboratory work 1 Topic: Topographic maps and plans. Scales. Conditional signs. Linear measurements on topographic maps and plans Purpose: To get acquainted with topographic maps and plans, scales, types of symbols. Master the measurement and construction of segments using graphic scales Work plan: 1. Topographic plan and topographic map 2. Symbols 3. Scales, scale accuracy 4. Linear measurements on topographic plans and maps 5. Construction of segments of a given length using a transverse scale 6. Measuring the length of broken and curved segments 7. Homework (Individual settlement and graphic work)

1. Topographic plan and topographic map A topographic plan is a reduced and similar image on paper in conventional signs of horizontal projections of the contours of objects and the relief of a small area without taking into account the sphericity of the Earth. According to the content, plans are of two types: contour (situational) - they depict only local objects; topographic - local objects and relief are depicted.

1. Topographic plan and topographic map According to the content of the map, there are the following types: general geographical - they show the earth's surface in all its diversity; special purpose maps (soil maps, peat deposits maps, vegetation maps, etc.), on which individual elements are depicted with special completeness - soils, peat deposits, vegetation, etc. Maps are conditionally divided into three types according to the scale: small-scale (smaller than 1:); medium-scale (1: - 1:); large-scale (scale from 1: to 1:10,000); Scales of plans - larger than 1: Topographic map - a reduced generalized image in conventional symbols on paper of horizontal projections of the contours of artificial and natural objects and the relief of a significant area of the Earth, taking into account its sphericity.

2. Conventional signs Conventional signs that are used to designate on plans and maps various items localities are the same for all of Russia and are divided into 2 groups according to the nature of the image. Scale (areal) symbols serve to depict objects that occupy a significant area and are expressed on the scale of a map or plan. An areal symbol consists of a boundary symbol of an object and icons that fill it or a symbol of color. At the same time, terrain objects are depicted in compliance with the scale, which makes it possible to determine from a plan or map not only the location of the object, but also its size and shape. Off-scale are called such conventional signs, by which objects of the area are depicted without observing the scale of the map or plan, which indicates only the nature and position of the object in space in its center (wells, geodesic signs, springs, pillars, etc.). These signs do not allow us to judge the size of the depicted local objects. For example, on a large-scale map, the city of Tomsk is represented as an outline (to scale); on the map of Russia as a point (out of scale).

2. Conventional signs According to the way they are depicted on the map, conventional signs are divided into 3 subgroups: geometric shapes. Graphic symbols are used to depict objects of a linear type: roads, rivers, pipelines, power lines, etc., the width of which is less than the accuracy of the scale of this map. B. Color conventions: shading with color along the contour of the object; lines and objects of different colors. C. Explanatory symbols - supplement other symbols with digital data, explanatory inscriptions; are placed next to various objects to characterize their property or quality, for example: bridge width, tree species, average height and thickness of trees in the forest, carriageway width and total road width, etc. On topographic maps, symbols are indicated in a strictly defined sequence: conventional signs are always shown on the right and only on educational maps.

3. Scales, scale accuracy When drawing up maps and plans, horizontal projections of segments are depicted on paper in a reduced form, i. on a scale. Scale of the map (plan) - the ratio of the length of the line on the map (plan) to the length of the horizontal projection of the terrain line:. (1) Scales are numerical and graphic. Numerical 1) In the form of a simple fraction:, (2) where m is the degree of reduction or the denominator of the numerical scale. 2) In the form of a named ratio, for example: in 1 cm 20 m, in 1 cm 10 m Using scales, you can solve the following problems. 1. According to the length of the segment on the plan of a given scale, determine the length of the line on the ground. 2. According to the length of the horizontal projection of the line, determine the length of the corresponding segment on the scale plan.

3. Scales, scale accuracy In order to avoid calculations and speed up work, as well as improve the accuracy of measurements on maps and plans, graphic scales are used: linear (Fig. 1.2) and transverse (Fig. 1.2). Linear scale - a graphic representation of a numerical scale in the form of a straight line. To build a linear scale on a straight line lay a series of segments of the same length. The original segment is called the base of the scale (O.M.). The base of the scale is the conventionally accepted length of segments plotted on a linear scale from zero on the right side of the linear scale and one division on the left side, which in turn is divided into ten equal parts. (M = 1:10000). The linear scale allows you to evaluate the segment with an accuracy of 0.1 fractions of a base accurately and up to 0.01 fractions of a base per eye (for a given scale) m 200 base

3. Scales, scale accuracy For more accurate measurements, a transverse scale is used, which has an additional vertical construction on a linear scale. Transverse scale After setting aside the required number of scale bases (usually 2 cm long, and then the scale is called normal), restore the perpendiculars to the original line and divide them into equal segments (into m parts). If the base is divided into n equal parts and the division points of the upper and lower bases are connected by inclined lines as shown in the figure, then the segment. The transverse scale allows you to estimate the segment exactly at 0.01 shares of the base, and up to 0.001 shares of the base - by eye. base A e g 3 p 1 2 f d 0 B m n n c

3. Scales, scale accuracy The transverse scale is engraved on metal rulers, which are called scales. Before using the scale bar, you should evaluate the base and its shares according to the following scheme. Example: Let numerical scale 1:5000, the named ratio will be: in 1 cm 50 m. If the transverse scale is normal (base 2 cm), then: one whole scale base (r.m.) - 100 m; 0.1 scale base - 10 m; 0.01 scale base - 1 m; 0.001 scale base - 0.1 m.

3. Scales, scale accuracy Scale accuracy makes it possible to determine which objects of the area can be depicted on the plan and which are not due to their small size. The reverse question is also being solved: on what scale should the plan be drawn up so that objects having, for example, dimensions of 5 m, are depicted on the plan. In order to be able to accept in a particular case definite decision, the concept of scale accuracy is introduced. In this case, they proceed from the physiological capabilities of the human eye. It is accepted that it is impossible to measure the distance using a compass and a scale ruler, more accurately than 0.1 mm, on this scale (this is the diameter of a circle from a sharply honed needle). Therefore, the maximum accuracy of the scale is understood as the length of the segment on the ground, corresponding to 0.1 mm on the plan of this scale. In practice, it is accepted that the length of a segment on a plan or map can be estimated with an accuracy of ± 0.2 mm. The horizontal distance on the ground, corresponding to a given scale of 0.2 mm on the plan, is called the graphic accuracy of the scale. Therefore, at this scale (1:2000), the smallest differences that can be identified graphically are 0.4 m. The accuracy of the transverse scale is the same as the accuracy of the graphic scale.

4. Linear measurements on topographic maps and plans Segments, the length of which is determined from a map or plan, can be straight and curvilinear. It is possible to determine the linear dimensions of an object on a map or plan using: 1. a ruler and a numerical scale; Measuring a segment with a ruler, we get, for example, 98 mm, or on a scale of -980 m. When evaluating the accuracy of linear measurements, it should be taken into account that a segment with a length of at least 0.5 mm can be measured with a ruler - this is the magnitude of the error in linear measurements using a ruler 2. measuring compass and linear scale; 3. compass-measuring and transverse scale.

4. Linear measurements on topographic maps and plans of a measuring compass and a linear scale; The measurement of segments using a linear scale is carried out in the following order: take the segment to be measured into the solution of the measuring compass; attach a compass solution to the base of a linear scale, while its right leg is combined with one of the strokes of the base so that the left leg fits on the base to the left of zero (on a fractional basis); count the number of integers and tenths of the scale base:

4. Linear measurements on topographic maps and plans of the measuring compass and transverse scale digitize the transverse scale (normal) on the map scale (in this case 1:10000): .0 7 o. m. 0.001 o.m. 0.8 o.m o.m.

5. Construction of segments of a given length using a transverse scale Let it be required to plot a segment on a map at a scale of 1:5000, the length of which is 173.3 m. 1. Make a painting in accordance with the scale of the map (1:5000): tenths, hundredths and thousandths of a scale base. 3. Dial on the measuring compass using a transverse scale the calculated number of whole, tenths, hundredths and thousandths of the scale bases. 4. Draw a segment on paper - pierce a sheet of paper and circle the resulting two points with circles. The diameter of the circles is 2-3 mm. Section length Fig. 6. Making a segment of a given length on paper

6. Measurement of the length of broken and curved segments Measurement of broken segments is carried out in parts or by the method of extension (Fig. 7): set the legs of the meter at points a and b, lay the ruler along b-c direction, move the meter leg from point a to point a1, add a segment b-c, etc. a а1а1 а3а3 c e d b а2а2 7. Measurement of the length of broken segments by the method of extension Measurement of curved segments is possible in several ways:. 1.using curvimeter (approximate); 2. by extension; 3.constant solution meter.

7. Problem solving 1. The length of the line on the map (2.14 cm) and on the ground (4280.0 m) is known. Determine the numerical scale of the map. (2.48 cm; 620 m) 2. Write a named scale corresponding to the numerical scale 1:500, 1: (1:2000, 1:10000) 3. On the plan M 1:5000, display an object whose length on the ground is 30 m. Determine the length of the object on the plan in mm. 4. Determine the limiting and graphical accuracy of the scale 1:1000; 1: Using a measuring compass and a normal transverse scale, set aside a segment of 74.4 m on a piece of paper on a scale of 1:2000. (1415 m on a scale of 1:25000) 6. Using a transverse scale, determine the distance between the absolute marks of the points - 129.2 and 122.1 (square of the training map). (141.4 and 146.4 (square 67-12). 7. Measure the length of the stream (up to the Golubaya River) (square 64-11) using a curvimeter and a compass-measuring device with a solution of 1 mm. Compare the results. 8. Horizontal the distance between two points on the plan M 1:1000 is 2 cm. Determine the distance between these points on the ground.

References 1. Guidelines for laboratory work on the discipline "Geodesy and Topography" for full-time students of the direction "Geophysical methods of prospecting and Exploration of mineral deposits" and "Geophysical methods of well research". - Tomsk: ed. TPU, 2006 - 82 p. 2. Fundamentals of geodesy and topography: tutorial/ V.M. Perederin, N.V. Chukharev, N.A. Antropova. - Tomsk: Publishing House of the Tomsk Polytechnic University, p. 3. Symbols for topographic plans at scales 1:5000, 1:2000, 1:1000, 1:500 / Main Directorate of Geodesy and Cartography under the Council of Ministers of the USSR. – M.: Nedra, p.