9 Different Types of Surveying | Surveying Instruments & Uses | Triangulation and Trilateration Surveying
Different Types Of Surveying | Difference between Triangulation and Trilateration | Types of Surveying Techniques | Surveying Instruments and Their Uses
What is Surveying
Surveying is a branch of science which is mostly consisted of the measurement of land, air, and water. It also includes the operation, installation, and maintenance of equipment that is used to carry out those functions.
Surveying is the activity of gathering information on aspects of the Earth’s surface or subsurface. The information is used to complement, interpret, or formulate science or engineering models.
Surveying includes the global, topographic, hydrographic, geodetic, photogrammetric, and mapping surveys.
Different Types of Surveying
1. Land surveying
Land surveying involves measuring and determining property boundaries. All property transactions, including buying, selling, mortgaging, and leasing, are based on land borders.
A reliable and efficient real estate market necessitates confidence in the location of property boundaries. Property boundary location and knowledge of issues that may impact land ownership necessitate specialized expertise.
Only registered land surveyors are legally permitted to conduct boundary surveys, portray specifics of property borders on plans, and draft subdivisions and certain types of lease plans.
2. Engineering surveying
Contrasting land surveying, engineering surveying is concerned with the construction and maintenance of physical facilities (such as roads, bridges, and canals).
The American Society of Civil Engineers (ASCE), an organization of professional engineers in the United States, defines engineering surveying as “the supervision and interpretation of data used for the purpose of evaluating the suitability of locations and materials for specific projects; and the development, critique, or verification of methods used in evaluating such locations and materials.” This definition encompasses survey planning on projects in progress.
3. Marine Surveying
Maritime surveying is also referred to as marine engineering, marine geodesy, and nautical and aeronautic surveying.
4. Hydrographic Surveying
Hydrographic surveys are concerned with the determination of the navigable channels of major bodies of water, canals, and rivers and streams.
Furthermore, surveys for lakes and dams are hydrographic surveys.
5. Mining surveying
Mining surveying is used to describe the related disciplines of mineral surveying, geochemistry, geophysics. and construction surveying.
6. Petroleum Surveying
Petroleum surveying is a scientific discipline that concerns the assessment of petroleum reserves and statistical analysis of production data to determine future production trends.
It includes the exploration, appraisal, and evaluation of oil and gas fields. Further petroleum information can be obtained from:
7. Geodetic surveying
Geodetic surveyors are responsible for taking extremely exact measurements in order to establish the shape and size of the planet and to follow the movement of continents. Their readings are used to monitor sea-level rise, earthquakes, and satellite tracking.
Geodetic surveyors work on the creation of coordinate systems and datums that are utilized in the creation of maps and plans.
8. Landscape surveying
Landscape surveying deals with the design of public parks, golf courses, and other landscaping or outdoor features.
9. Astronomical Surveying
Astronomical surveying is the science of mapping celestial objects, constellations, stars, and nebulae with a view to determining and correcting planetary positions.
It includes the theoretical discussion of astronomical parallax (the measurement of apparent displacement between two identical points in different locations).
10. Plane Surveying
In plane surveying, the work is done entirely on a horizontal plane and the entire operation consists of measuring and determining property boundaries. It is that type of surveying in which the mean surface of the earth is considered as a plane and the spheroidal shape is neglected.
Importance of Surveying
- The development of land use and zoning regulations is based on surveys.
- Acquiring and developing lands is a major issue in the public sector (nations, states, cities, etc.), private sector, agriculture, water resource management, and other fields.
- Surveys are required or authorized in several countries to determine the appropriate boundaries for state-owned lands to be purchased by private parties. Other surveys are used to administer property rights as they relate to taxes or other charges levied on land for public resources (roads, ports).
- Surveying is a fundamental part of geography, geology, engineering, construction, architecture, and land management. In the construction industry, more than half of the world’s workforce is engaged in surveying.
- Surveying also has an effect on the economy as a whole; without it, the government cannot create accurate maps to determine property values or develop roads and highways. Additionally, without local surveys, the government would not be able to issue land and building permits.
- A surveyor’s work is often considered a necessary profession or profession of choice. Surveying is often considered a necessary part of being a realtor or architect as it helps know where everything is located on the property along with how much space you can use to build your home on that piece of property. Surveying is also important in art and architecture as it determines the size and shape of each piece (such as paintings or architectural design).
- The global positioning system (GPS) navigation system is based on satellite survey data obtained by surveyors. If a GPS system is not functioning properly, the user will not have a good idea of where they are on the earth.
- Surveying is also used in print media as well as online news outlets such as maps and charts. The accuracy and detail of these maps can help determine various types of geography.
Difference Between Triangulation and Trilateration
Triangulation is the procedure of finding the position of a point in surveying by measuring only angles to it from known points at each end of a specified baseline, rather than calculating distances to the point directly, as trilateration does.
After that, the point can be established as the third point of a triangle with one known side and two known angles.
Triangulation can also refer to the precise surveying of huge systems of triangles, known as triangulation networks.
Trilateration is a surveying process in which the lengths of the sides of a triangle are measured, usually electronically, and angles are derived based on this information.
A surveyor can acquire various distances and angles that would not otherwise be quantifiable by erecting a sequence of triangles near to one another.
Because of the difficulty of the computations needed, trilateration was formerly infrequently used in compared to triangulation, a method for finding two sides and an angle of a triangle from the length of one side and two angles.
However, with the advancement of electronic distance-measuring instruments, trilateration has become a frequent and favored approach.
The field techniques for trilateration are similar to those for triangulation, with the exception that only lines are measured while all angles are computed.
Distinction Between Land Surveying and Land Information
Land information is about getting the information about locations on the Earth’s surface (e.g., real estate properties).
Land surveying is about measuring, charting, and mapping locations on the Earth’s surface.
The land information and land surveying are similar in the sense that they both deal with mapping. They both have cartographer.
The differences lie in what they map. Land information deals more with maps containing boundaries of real estate properties (ownership).
Land survey deal with boundaries others than ownership (e.g., roads, parcels).
Types of Surveying Techniques
1. Boundary surveying
Boundary surveying is concerned with the complete establishment of property lines according to law.
It includes the preparation of plats, diagrams, and maps necessary to determine exact location and description for every parcel of land in a survey area.
The boundary survey should provide the evidence needed to establish a permanent record of our work as well as serve as a basis for future actions related to real property.
The preparation of descriptions, evidence, and confirmations in support of permanent records is included in this type of surveying.
2. Topographic surveying
Topographic survey is the survey of ground elevation, slopes, and topography.
It includes all other types of land surveying such as geodesy (measurement of the shape and size of the planet), hydrography (surveys of water features), photogrammetry and photogrammetric scanning, datum surveying, astronomic surveying (surveys of stars and nebulae).
Topographic surveying is the survey of vertical and horizontal aspects of land. Basically, topographic surveying deals with a variety of global phenomena such as water, land, slope, rivers, and mountains.
3. Cadastral surveying
Cadastral surveying is concerned with the legal platting of land parcels. It is a means of defining the boundary characteristics (e.g., lot, block, tract, parcel), lot lines, and access routes in order to establish the ownership of land and to transfer or convey title from one person or owner to another person or owner.
4. Topographical and hydrographic surveys
Topographical surveys are divided into two types: topographic and hydrographic (marine).
Topographic surveys are concerned with the determination of elevations, shapes, and areas of land and its surface features.
Hydrographic surveys deal with the measurement of depths, widths, and other elements related to the control of water (rivers and lakes).
5. Road surveys or highway surveys
Road surveys and highway surveys, also known as route surveying, deal with the location and alignment of roads and highways.
The two types of roads or highways that are surveyed are public roads (roads owned by the government) and private roads (roads that are privately owned).
6. Layout surveys
Layout surveys or layout plans, deal with the preparation of drawings showing the plan of buildings such as apartments, schools, condominiums.
7. Astronomical surveying
Astronomical surveys deal with the measurement of positions and motions of celestial bodies.
8. Geodetic surveying
Geodetic surveying deals with the methods and techniques used in measuring large distances over the Earth’s surface (e.g., doubling rod method, plane table method, satellite surveying).
Geodetic surveys determine dimensions of the earth’s shape and gravity field for mapping purposes.
Maintenance of the object register is an aspect of geodetic surveying that is associated with civil engineering projects because it determines land ownership.
9. Aerial surveys or aerial mapping (creep)
Aerial surveys or aerial mapping deals with the use of unmanned aerial vehicles to collect data from a point of view from which ground features cannot be seen.
It is an effective means for recording large areas with limited access.
10. Biology surveys
Biology surveys provide information for the conservation of natural resources and ecosystems (e.g., wildlife, plants, climate).
11. Geology surveys
Geology surveys are used to study earth materials such as rocks, soil, and geological formations that can influence land planning decisions (e.g. for water resources, municipal sewer systems, and power transmission lines).
12. Minerals surveys
Minerals surveys deal with collecting geological information about minerals (minerals) that exist in the earth’s crust.
They may assist in planning for mineral exploration and development of commercializable deposits for extraction of valuable materials (e.g., gold ore).
Surveying Instruments and Their Uses
There are several key types of equipment and tool used. They include;
1. Surveying Chains
The surveying chain is used to determine the length of a line on the ground. When compared to a tape, it provides more accurate measurements.
A chain is a surveying device made composed of galvanized mild steel connecting links.
Mild steel wire is bent into a ring and connected with three small circular or oval rings. Each connecting link is 20 cm long.
A tally marker or a particular joint is occasionally fitted to mark the 5 metre distance.
The chain’s overall length is 20 or 30 meters, with a brass grip on each end. Swivel joints are included on the handles so that they can be readily turned while surveying without becoming twisted.
2. Measuring tape
A measuring tape is an instrument that measures lengths to approximately one-millimeter accuracy. It may be either straight or crosstable in design.
The unit most often used in the United States is the inches per foot length; in Britain, it is the foot per inch (foot) length.
The tape is a measuring instrument used to measure distances of horizontal or vertical lines.
It is the most basic surveying instrument and consists of a strip of metal or wood that extends continuously in both directions, usually between 0.25 and 1.0 inches wide. When laid on two parallel surfaces, it indicates the distance between them.
The two ends are attached to a transverse scale, which records distance in feet (or meters) along the longer edge and in hundredths of an inch on the shorter edge of the strip.
The main components of the theodolite include the telescope, vertical circle, horizontal circle, and leveling screws.
It is used to measure angles of an object relative to some other object or objects in a horizontal plane using the principle of triangulation to locate their position.
By measuring a known angle between two adjacent land features that are observed from one point, the coordinates of that point can be determined using trigonometry.
The theodolite is used to measure horizontal angles by a visual method called angle to angle and vertical angles by a plane table.
4. The Automatic Level
The automatic level is an electronic instrument used for determining elevation and is operated either manually or automatically.
The automatic level runs on batteries and can be attached to a car with an aerial that transmits radio signals back to the receiver. It measures levels of inclines, slopes, and declines.
5. The Map Levels
Map levels are used to verify contour lines and elevations. They are made of paper and come in different sizes and colors.
Some map levels are harder to handle than others, depending on the plasticity of the paper used in making it.
Their length is usually 1:25,000 or smaller with a scale of 1:2,500 or smaller. For larger scales (1:1,000), map frames are used instead of map levels
6. The Theodolite Level
The theodolite level is used to measure vertical angles by a visual method called angle to vertex.
It is an optical instrument that can be attached to a theodolite for determining vertical angles more accurately.
This instrument is composed of three parts- a telescope, an inverted prism and mirror, and a glass plate with an engraved scale.
7. Compasses and Clinometers
Compasses are used to maintain alignment on a straight path in a horizontal plane while clinometers are used to measure the angle or elevation of slopes.
The compass is composed of a compass card with two prisms on the card and two binnacle casings at the bottom. One prism is for north and the other is for east or west.
The two small cups placed opposite to one another on either side of the card must be lined up with the North Pole and mark zero.
8. Dumpy level
A dumpy level is an instrument comprised of a hollow tube filled with a liquid. It’s used to detect horizontal planes, especially when it is unclear whether the plane is inclined or not.
A bubble in the tube moves as a result of gravity and indicates whether the plane is horizontal or inclined. A small circular vial containing mercury usually serves as the liquid.
9. Prism Square
The prism square is a right triangle with one side flat and 45 degree angles made by cutting off (the hypotenuse).
Prism devices are used to hold control points at a safe and convenient height for laser precision.
For improved accuracy, these devices can be installed on surveying poles and used in conjunction with electronic distance measurement (EDM) instruments.
10. The Plumb Bob
The plumb bob is an instrument used to determine the level in vertical lines. It has a terminal weight to which is attached a string or wire.
The plumb bob is adjusted and held in a vertical position with the string then being allowed to hang freely.
The length of the string is measured from the end that is attached to the terminal weight.
11. Scales and Protractors
Scales are used for measuring distances on maps, and protractors are used for measuring angles on maps using a transversal scale
12. Magnetic Locators
The magnetic locator is used for locating materials by applying a magnetic field. It consists of two magnets (one for north and one for east), a metal casing around the magnet, and a coil of wire.
The magnets are placed so that they point toward each other when the device is in use.
The location of the other magnet is determined by placing the two magnets together within range of one’s hand held compass or electronic compass, with one edge of one magnet directly underneath the other magnet.
13. Total Station
A total station is an instrument that can be used for a variety of purposes such as leveling, finding the distance between two points, measuring angles, calculating bearing from compass bearings or mapping.
The total station consists of a base with legs attached to its base for stability, a telescope and an electronic level indicator.
A tripod is a set of three legs on which a piece of equipment such as a camera or telescope can be mounted to enable it to be adjusted at different levels.
15. Slope Aspect Ratio
The slope aspect ratio is the ratio of horizontal to vertical distance between two points on an inclined surface, used for determining the angle that needs to be measured with an inclinometer.
16. Plumbing Fork
The plumbing fork is a tapered tool used to check the vertical and horizontal position of pipes in a drain or meter.
The tines are graduated in increments of one inch (2.54 cm), and the tines are calibrated to indicate depth by means of a series of notches on their sides.
The width of the tool is equal to half the depth of the pipe being tested.
17. Levelling Staff
A levelling staff is an instrument used for measuring horizontal plane by a visual method called angle to the horizon.
It is composed of three parts- a telescope, an inverted prism and mirror, and a glass plate with an engraved scale.
A peg is a device used for measuring linear distances. It consists of a metal bar with an eye and a movable length of chain holding the eye on one end.
The adjustable end of the chain consists of a pin or peg that is attached to a plumb bob.
An arrow is a device used for measuring linear distances. It has a pin at one end that fits into the peg of the measuring chain and slides freely through it, with an arrowhead at the other end to indicate the direction.
20. Surveyor’s safety vest
A surveyor’s safety vest is a piece of protective clothing worn by a surveyor. It has multiple pockets to carry book, pencils and other small tools.
1. What is Triangulation in Surveying?
The measurement of triangles is a method used to determine the shape of an object. Surveying involves the triangulation of points that are distributed on the surface of a given area.
Triangulation in surveying refers to dividing the region into triangles while observing altitude angles and distances between any two of these triangles.
2. What are the uses of surveying?
Surveying has several useful uses. The main uses of surveying include:
(a) survey of land for sale and rent,
(b) determining the boundaries of public or private property,
(c) legal survey, and
(d) the construction of streets and buildings.
3. What are the different types of surveying?
There are primarily two types of surveying, namely:
(a) Plane surveying
(b) Geodetic Surveying
4. What is Plane Surveying?
Plane surveying is a method used to survey land by measuring the horizontal and vertical distances between two or more points on the ground.
5. What is chain surveying?
Chain surveying is the branch of surveying in which only linear measurements are made in the field. This is suitable for the survey of small areas with simple details and an area that is fairly flat.
It derives its name from the fact that the principle equipment commonly used is the chain.
6. What is the difference between triangulation and trilateration?
In triangulation, triangles are formed on the surface of an area using a single known point. In trilateration, three or more known points are used to determine the location of an unknown point on the surface of an area.
7. What is geodetic surveying?
Geodetic surveying is a method used to determine the elevation of any given point on the surface of the earth. It involves measuring horizontal and vertical distances between two points.
8. What is compass surveying?
Compass surveying is a method used to measure horizontal distance only. Two surveyors split the work by taking measurements alternately with the compass and then comparing the results later.
9. What is geophysical surveying?
Geophysical surveying uses aerial photography to determine earth’s surface and underground formations, and to locate faults, coreholes, underwater routes, etc.
It involves measuring horizontal distances between points at different levels on the surface above and below the water surface.
10. What is photographic surveying?
Photographic surveying is a method for determining the horizontal and vertical distances between points at different levels on the surface of an area. It uses aerial photography.
11. What is terrestrial plane surveying?
Terrestrial Plane Surveying involves taking measurements from an aircraft that flies above the field being surveyed, and taking measurements from each part of the survey area to be surveyed, after which all the measurements are combined to produce a single set of data.
12. What is magnetic surveying?
Aerial photography using a magnetometer as part of the survey equipment is called magnetic surveying, which is also known as Geomagnetic Surveying or Magnetic Survey.
13. What is the difference between surveying and leveling?
Surveying is the art of determining the relative position of points on, below, or above the surface.
Leveling is a subset of surveying whose primary goal is to determine the elevation of points in relation to a datum.
14. What is the difference between surveying and mapping?
The primary goal of a survey is to determine the relative position (in three dimensions) of points on, below, or above a surface.
Mapping involves the representation of these points using graphic symbols with reference to some other map projection.
15. What is the difference between surveying and geodesy?
Surveying deals with measuring distances and angles in order to record or determine locations, elevations, shapes and landforms on Earth’s surface.
Geodesy is the branch of science that deals with the measurement of the Earth’s shape and topography.
16. What is levelling?
In geodetic surveying, a measuring device, known as a levelling staff or a levelling rod or level, is used to take precise measurements of horizontal and vertical distances between points in an area.