Difference Between Plane and Geodetic Surveying
Difference Between Plane and Geodetic Surveying
Introduction
Surveying is simply the technique or technology of making scientific measurements on, above, or below the earth’s surface in order to determine points for a plan or map.
When the region of surveying is small but the scale at which the result is plotted is vast, it is referred to as a plan, and vice versa, it is referred to as a map.
Surveying is widely employed in practically all civil engineering projects such as building, bridges, reservoirs, dams, railways, highways, irrigation projects, and so on.
Surveying can be classified based on various factors such as the field of survey (such as land survey, marine survey, photogrammetric, etc.), the object of surveys (such as engineering purpose, military purpose, etc.)
The method of survey (such as triangulation, trilateration, etc.), and the instruments used (Like chain surveying, theodolite surveying, levelling, etc.). However, plane surveying and geodetic surveying are the most important types of surveying.
What is Plane Surveying
Plane surveying is a branch of surveying and map making that deals with the measurement of an object from air. It includes the use of remote sensing, satellites, photogrammetry, and radar among other tools.
The plane surveyor can be someone who uses these tools to create maps for a particular project or it may be an independent contractor.
Plane surveying is a typical method of determining land composition and topography that entails treating a specific area of land as if it were a flat plane. The ground being appraised is regarded as a level plane in plane surveying.
Surveyors employ a number of equipment to position points on that plane, which is referred to as the plane table.
Plane surveyors can also help formulate land development plans as well as strategic planning for organizations such as governments or businesses in order to maximize their goal.
Plane Surveying Overview
Plane surveying is a type of surveying in which the earth’s surface is regarded to be a plane surface.
This is the most often used type of surveying. This method is employed when the region to be surveyed is small (less than 260 square km), as it ignores the curvature of the earth.
To perform calculations, triangles are typically created on the ground, and these triangles are also presumed to be plane triangles, with the rules of plane triangles being utilized to perform the computations.
The area to be surveyed and the error connected with the survey results are positively correlated, which means that the larger the area, the greater the mistake.
As a result, this method is not appropriate for more exact or precise large-area surveying. Plane surveying is typically used in engineering projects.
This method is typically used to survey for the location and construction of railroads, highways, cannels, and landing fields.
What is Geodetic Surveying
Geodetic Surveying is the branch of surveying that works with areas so large that the true shape and proportions of the earth must be taken into account.
Its major goal is not to ascertain the exact figure of the Earth, but to develop a very precise and tight control for the coordination of all other surveys.
This element is frequently neglected, and the scientific aspect is sometimes overemphasized to the disadvantage of the more practical side.
True, the earth’s dimensions must be known in order to compute exact positions, but it is also obvious that before these dimensions can be established, the geodetic trigonometrical survey must be completed.
Actually, geodetic surveys are carried out for two reasons:
- First, to establish rigid co-ordination of all surveys by basing the computations on a previously known value of the earth’s dimensions;
- Second, as the survey extends or is completed, additional data becomes available for a check on the Figure used, or, if necessary, for the calculation of another figure to fit more closely the territory being surveyed.
Horizontal and vertical networks that span the country serve as the principal spatial reference system for mapping, boundary demarcation, and other geomatics applications.
Geodesy’s practical applications include monitoring earth movement and establishing the precise location of locations on the earth’s surface for use in satellite tracking and global navigation.
Geodetic Surveying Overview
Geodetic surveying is a type of surveying in which the curvature of the earth is taken into account when taking measurements on the earth’s surface.
That is, the earth’s real spherical shape is taken into account. This is often referred to as trigonometrical surveying. Spherical triangles are created, and computations are performed using spherical trigonometry.
Measurements are taken with high precision devices in this procedure. This method is used to determine or construct control points for other surveys, as well as to cover great distances and territories.
Each geodetic station’s position is expressed using longitude and latitude, and the Global Positioning System (GPS) is typically utilized for this purpose.
Difference Between Plane Surveying and Geodetic Surveying
The following are the major differences between the two types of surveys.
Description
Plane surveying is a sort of surveying in which the earth’s mean surface is assumed to be plane, i.e., two dimensional.
Geodetic surveying is a sort of surveying in which the earth’s mean surface is considered to be spherical, i.e., three dimensional.
The Lines Created by Connecting Any Two Points
Plane surveying: Straight lines are constructed by connecting any two locations (the same angles are plain angles).
Geodetic surveying: Arch-as the same angles are spherical, the lines created by joining any two points are considered arch-as the same angles are spherical.
Spherical nature of the Earth’s surface
Plane surveying: The influence of the earth’s round nature is never taken into account.
Geodetic surveying takes into account the spherical nature of the earth’s surface.
The Area Involved
Plane surveying: This sort of surveying entails tiny regions that are less than 260Km2.
Geodetic surveying: This type of surveying covers areas larger than 260 km2.
Accuracy
The precision of plane surveying is poorer.
Geodetic surveying has a better level of precision.
Instruments
Plane surveying use standard instruments such as a chain, measuring tape, theodolite, and so on.
Geodetic surveying use more precise tools and cutting-edge technology such as GPS.
Nature
In nature, plane surveying is done on a local level by individual organizations and enterprises.
Geodetic surveying is carried out by governments and state departments.
Application
It is utilized in common civil engineering survey project work in plane surveying.
In geodetic surveying, it is commonly utilized in typical civil engineering survey projects.
Cost
Plane surveying is the most cost-effective and simple method of surveying.
It is the most expensive and difficult method of surveying in geodetic surveying.
Triangles
Plane surveying: A plain triangle is one created by any three points.
Geodetic surveying: A spherical triangle is one created by any three points.
FAQs
What is the difference between geodetic and plane surveys?
The main difference between the two surveys is that plane surveying assumes the Earth’s surface is flat, while geodetic surveying assumes that the surface of the Earth is spherical.
This means that when you are taking measurements for plane surveying, you take into account only one dimension along which you need to measure. While for geodetic survey, you take into account three dimensions such as horizontal (x-axis), vertical (y-axis) and z-axis.
Where can you perform geodetic surveying?
Since the Earth is a sphere, all the measurements of lengths, angles, and areas are affected by the curvature of the Earth. So geodetic surveying is best performed on regions or territories that are large in size.
What is plane survey in civil engineering?
Plane surveying is a sort of surveying in which the earth’s surface is thought to be flat and the curvature of the earth is ignored. A straight line connects any two locations, and polygonal angles are plane angles.
What is the purpose of plane surveying?
Plane surveying is a typical method of determining land composition and topography that entails treating a specific area of land as if it were a flat plane. Because the Earth is not flat, this type of land surveying works best for limited sections of land.
What is the basic assumption for plane surveying?
There are no vertical distances or directions. The plumb line’s direction is the same at all sites within the survey’s boundaries. Every angle (horizontal and vertical) is a plane angle. Elevations are given in relation to a datum.
How does geodetic surveying differ from plane surveying under what circumstances is it necessary to conduct a geodetic survey?
Geodetic surveying is mostly used to identify exact positions on the earth’s surface. Trigonometrical surveying is another name for it.
Because surveying is done in limited areas, the curvature of the earth is neglected in-plane. When compared to geodetic surveying, the degree of accuracy is poor.
What are the uses of geodetic surveying?
Geodetic Surveying is used to obtain horizontal control points. Geodetic Survey: Geodetic surveying refers to surveys that take the curvature of the earth into account. All of the lines on the surface are curved, and the triangles are spherical.
Is geodetic surveying accurate?
Geodesy is one such branch on the surveying tree. These ultra-accurate land-mapping systems make use of the earth’s curvature as well as its own shape and position in space.
What are the limitations in plane surveying?
Plane Table Survey Disadvantages
- The process of transferring and re-orienting the plane table from one location to another is quite time-consuming.
- Because the plotting work is done in the field, this sort of surveying is not practicable in rainy or windy places.
- The plane table and its accessories are bulky and awkward to transport.
- The process of adjusting the plane table is not time-efficient.
Plane Table Survey Advantages?
- As the equipment is compact and lightweight, it can be moved easily.
- The process of transferring and re-orienting the plane table from one location to another is quite simple.
- The plotting work can be done in a number of ways.
- Because the table is equipped with an alidade, the level of accuracy is high. This type of surveying is very suitable for construction planning.
Geodetic surveying advantages?
- Being a survey technique, it can be used for purposes like surveying, construction planning, and land leveling.
- The process of moving is easy.
- The plotting work does not require a lot of instruments.
- The process of transferring and re-orienting the plane table from one location to another is simple.
- The accuracy level is high.
Geodetic Surveying Disadvantage?
This type of surveying is expensive. The instruments used are very expensive and may cause a dent in your budget if you don’t buy them second hand. Moreover, they require regular maintenance.
Sometimes it can be hard to locate the required equipment since not all surveying companies own or maintain such equipment.
What is geodetic engineer?
The practice of Geodetic Engineering is a professional and systematic act of acquiring physical data on the earth’s surface using precision instruments.
It is also the scientific and methodical processing of these data and their presentation on graphs, plans, maps, charts, or publications.
Does geodetic engineer have board exam?
A person who wishes to be qualified and practice as a Geodetic Engineer must take and pass the licensure exam. The PRC administers the board test twice a year, in August and October. To pass the test, an applicant must obtain a passing average of 75%, with no grade lower than 50%.
The board exam contains a total of 200 multiple choice questions to be answered within 4 hours. The passing average is 75%.
Geodetic Engineer Job Description?
Geodetic Engineers are also called Geodesists. To become one, a person must study and undergo training that covers surveying principles and theories; computer mapping technologies; and Geographic Information Systems (GIS).
In addition, a Geodetic Engineer needs to have an in-depth knowledge of the use and application of surveying and geodetic instruments.
Geodetic Engineering objective?
The main objective in Geodetic Engineering is to conduct all types of surveys that are required for construction.
For example: topographic mapping; levelling and contour surveys; waterway, stream, lake surveys; control station operations; triangulation; design of tunnels and bridges; as well as designing and plotting maps.
Plane surveyor salary?
A plane set surveyor can earn on average around $20,000 to $40,000 or more in a year. The salary depends on the experience of the surveyor
What is Geodetic surveyor’s salary?
The starting salary of a geodetic surveyor is around $20,000 to $40,000 or more per year.
What equipment or methodology does plane surveying use?
Standard instruments used in plane surveying are: plane table; tripod for the plane table; alidade/protractor/vernier scale; compass/level; transit, and measuring tapes.
These are the essential equipment used in plane surveying.
Plane Surveying Objectives?
The basic objective in Plane Surveying is to determine the extent of land within a parcel for the purposes of selling, buying, and developing it, based on the results obtained from plane surveying. It may be required to determine differences in elevation between two adjacent lots.
Why is Backsight called positive sight?
Actually, the rear is a good place to start when leveling. The backside is the first reading obtained after setting up the instrument at that specific location. As a result, hindsight is always additive in nature. As a result, it’s also known as plus sight.
What is the fundamental principles of plane surveying?
The main principles of plane surveying are as follows: Finding the location of a point by measuring it from two points of reference: Two control sites are chosen in a region and the distance between them is precisely calculated.
What is traverse method?
Traverse is a surveying approach for establishing control networks. Geodesy makes use of it as well.
Traverse networks are constructed by installing survey stations along a line or course of travel and then using the previously surveyed sites as a base for surveying the following point.
What are the benefits of surveying?
Besides helping in the earth’s exploration, surveying has great benefits.
It provides information about locations and elevations of terrain. The data obtained are used to build maps and charts, especially for military needs.
In civil engineering, land surveys provide the basis for building construction plans, road layout work, pipeline mapping (both surface and underground), navigational charts of lakes and rivers, boundary surveys (at national level) etc.
What is the greatest contribution of surveying to the world?
Surveyors are essential in all aspects of land development, from land subdivision planning and design to final road, utility, and landscaping construction. Surveyors are the first personnel on any construction site to calculate and record the land.
What do you understand about surveying and explain the importance of surveying in civil engineering?
Civil surveying is a type of engineering that involves assessing and recording information about a piece of land. These findings can subsequently be used to aid in the planning of construction projects.
The primary goal of civil engineering surveying is to discover the three-dimensional relationships between various places.
