Classification of Surveying Based on Instrument Used

Classification Based on Instrument Used

• Chain survey.
• Compass survey.
• Theodolite survey.
• Plane Table survey.
• Tachometric survey.
• Aerial Photographic Survey.
• Remote sensing.

Chain Surveying

• Surveying with a chain/tape
• Used for determining distance – a linear measurement
• Suitable for surveys of small extent on open ground.
• Purposes – to define boundaries of a piece of land or to take some details.
• Denotes measuring distance either with the help of a chain or tape
• Direct measurements.

Compass Surveying

• When area is flat, distances are measured in straight lines.
• When area is undulating or has obstacles, the line has to go in a zig-zag fashion.
• Direction of the lines is necessary when required for plotting in paper.
• Compass used to define direction.
• Compass gives bearing of a line.
• The bearing are required for plotting the line on paper.
• Every map has to be provided with a North.

Plane Table surveying

• In normal surveying, field observations are taken first and then plotting done in office.
• Plane table surveying involves simultaneous plotting along with taking field observations.

Advantages

• Rapid
• No field book required
• Mistakes of booking field notes avoided
• Can compare work on the field itself

Levelling

• The other types of surveys give only the horizontal dimension
• The vertical coordinates is defined by a level.
• Denoted as reduced level or elevation
• Used for defining alignment of roads, for setting of drainage lines etc.

Theodolite surveying

• Instruments such as chain, compass, level give one form of dimension.
• Theodolite is used for both horizontal and vertical measurement, in the form of angles.
• Works on the principle of optics.
• Used for defining angles unlike compass that gives only bearings.
• Highly used equipment.