Topographic survey is a mandatory type of work before starting construction on any site. Knowledge of the types, purpose and performance of topography will allow you to competently approach the issue of geodetic surveys and not be mistaken in choosing a contractor.
A land plot is usually acquired for the purpose of building residential or industrial construction, trade establishments. For such a transaction, as a rule, a certain package of documents is required, which includes a plan with the exact dimensions of the site and the proposed location of buildings and communications (underground and above ground). To draw up such documents, a topographic survey is required - this is a topographic survey, which will allow you to get maximum information about the nuances of the area. The only exceptions are agricultural areas, but even for them, topographic surveys are periodically ordered in order, for example, to exclude options for flooding seedlings with groundwater or rains in lowland areas.
Topographic survey concept
With topographic survey, a conditional zero point is determined, with which all other parameters of the site are correlated: ravines, lowlands, hills, etc. To get an accurate plan of the area, specialists carry out a whole range of works. All measurements carried out by them must comply with the generally accepted standard (GOST 22268-76).
Ground shooting happens:
- planned;
- high-rise;
- combined.
Planned (horizontal) survey allows you to determine the coordinates of the area. Vertical - the height of some base points.
Thanks to the topographic survey of the site, it is possible not only to accurately measure its dimensions, but also to determine the distance to the nearest objects, as well as the angles, the value of which is fundamentally important for some types of construction.
Topographic survey types
Topographic survey types are usually distinguished depending on the scale.
- Poderevnaya. This type, as a rule, is ordered for the purpose of further planning of landscaping. This assumes the exact location of the trees growing on the site.
- Super large. It is carried out on a scale of 1: 200. It is most often used for the purpose of arranging construction sites. Such a survey involves the most accurate measurement of the location and coordinates of existing buildings and other objects.
- "Five hundred". Conducted to a scale of 1: 500. "Five hundred" is used in drawing up detailed drawings, as well as general plans of utilities passing through the site.
- 1: 2000. This scale is typical when conducting a topographic survey of microdistricts, villages, villages and other settlements. In addition, it allows you to draw up an accurate plan of production enterprises (factories, plants, etc.).
Depending on the technological process, topographic survey is:
- Theodolite. Metric data for ground surveys are obtained using rangefinders and theodolite (astronomical and geodetic goniometric instrument).
- Stereotopographic. Specialists receive primary information using a stereo pair.
- Bussolnaya. This type of topographic survey is carried out by rangefinders and compass (instruments for obtaining data on horizontal angles on the ground).
- Menzular. It is produced with a beaker and kipregel (special geodetic instruments).
- Aerial photography. A method for obtaining a photographic image. Manufactured from aircraft (airplanes, helicopters, quadcopters, drones).
- Digital. Topographic survey method for obtaining an optical image. This image is transferred to digital media.
- Sonar. A method of obtaining information about the bottom of lakes, rivers and other bodies of water. Performed using sonar.
Purpose of topographic survey
Before starting any construction on the site, first, geodetic research work is performed, and then surveys. These works allow you to get the most accurate indicators of distance, angles and heights, to determine the boundaries and area of the site, as well as its geographical coordinates.
Topographic survey clarifies the data obtained, and also helps to build a three-dimensional model of the terrain. Recently, large-scale shooting is most often used. It serves the purpose of updating master plans and drawing up drawings.
Performing a topographic survey
Topographers consistently carry out a number of stages:
- Preparatory: conclusion of an agreement, preparation of planning documentation indicating the timing and scope of the study, visits to public authorities to obtain permits for conducting topographic surveys.
- Field: stage of the survey.
- Final: preparation of a technical report and delivery of work.
The cost and quality of any type of topographic survey is in direct proportion to the terrain and scale.
