What is surveying? Classification and principle of surveying Linear measurement chain surveying Errors in chain and tape Compass surveying

1. Chapter : 2
Part I :Surveying
Prepared by :Prof. Kajol Panchal
Diwaliba Polytechnic
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2. Topics
• What is surveying?
• Classification and principle of surveying
• Linear measurement chain surveying
• Errors in chain and tape
• Compass surveying
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3. What is surveying?
• Surveying is the science and art of determining the
relative positions of points above, on, or beneath
the earth’s surface and locating the points in the
field.
“Surveying is the art of and science of determining
the relative positions of various points or stations on
the surface of the earth by measuring the horizontal
and vertical distances, angles, and taking the details
of these points and by preparing a map or plan to
any suitable scale.”
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4. Objective of Surveying
• The object of surveying is to prepare a map or plan
to show the relative positions of the objects on the
surface of the earth.
• The map or plan is drawn to some suitable scale.
• It also shows boundaries of districts, states, and
countries too.
• It also includes details of different engineering
features such as buildings, roads, railways, dams,
canals etc.
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6. Use of surveying
The surveying may be used for following
purposes:
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• To prepare a topographical map which shows hills, valleys,
rivers, forests, villages, towns etc.

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• To prepare a cadastral map which shows the boundaries
of fields, plots, houses and other properties..

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• To prepare an engineering map which shows the position of
engineering works such as buildings, roads, railways, dams, canals.

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• Surveying is also used to prepare military map, geological
map, archaeological map etc.

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• For setting out work and transferring details from the map
on the ground.

12. Fundamental Principles of
surveying
Two basic principles of surveying are:
• Always work from whole to the part.
• To locate a new station by at least two
measurements (Linear or angular) from fixed
reference points.
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13. Always work from whole to the part.
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To locate a new station by at least two
measurements (Linear or angular) from fixed
reference points.

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• To locate a new station by at least two measurements
( Linear or angular) from fixed reference points.
• According to the second principle the points are located by
linear or angular measurement or by both in surveying. If
two control points are established first, then a new station
can be located by linear measurement. Let A & B are control
points, a new point C can be established.

16. Following are the methods of locating
point C from such reference points A
& B.
• The distance AB can be measured accurately and the
relative positions of the point can be then plotted on the
sheet to some scale.
• (a) Taking linear measurement from A and B for C.
• (b) Taking linear measurement of perpendicular from D to C.
• (c) Taking one linear measurement from B and one angular
measurement as ∕ ABC
• Taking two angular measurement at A & B as angles / CAB
and / ABC.
• Taking one angle at B as / ABC and one linear measurement
from A as AC.
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17. • Survey can be classified into various categories
depending on methods used and nature of the
field.
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Classification of
Surveying
Primary
Classification or
Primary Division
Secondary
Classification

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Primary Divisions of surveying

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Sr.
No.
Point of
Difference
Plain Surveying Geodetic Surveying
1 SURFACE The plain surveying is that type of
surveying in which earth surface is
considered as a plane and the
curvature of the earth is ignored.
The geodetic Surveying is that type
of surveying in which the curvature
of the earth is taken into account.
2 LINE In such surveying a line joining any
two stations is considered to be
straight.
The line joining any two stations is
considered as curved line.
3 TRIANGLE The triangle formed by any three
points is considered as a plane
triangle, and the angles of the
triangle are considered as plain
angles.
The triangle formed by any three
points is considered to be spherical
and the angles of the triangle are
considered to be spherical angles.
4 AREA Surveying is carried out for a small
area of less than 250 km2 .
Geodetic surveying is carried out for
a larger area exceeding 250 km2.
5 DONE BY R & B department, Irrigation
department, Railway department.
Survey of India Department.

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Secondary
Classification
Based on
instrument
Based on
methods
Based on Objects: Geological
survey Mine survey
Based on
nature of
field

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Based on
instrument
Chain Survey
Compass
survey
Plane Table
survey
Theodolite
survey
Tacheometric
Survey
Photographic
survey
Based on methods
Triangulation
Survey
Traverse
Survey
Based on Objects:
Geological survey
Mine survey
Archaeological
Survey
Military survey
Based on nature of
field
Land Survey
Marine survey
Astronomical
survey

22. Linear measurement chain surveying
Methods:
• Direct methods
• Optical methods
• E.D.M methods
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23. Instruments Used in Chaining
The following instruments are used while chaining.
• Chains
• Tapes
• Arrows
• Ranging rods and offset rods
• Laths & Whites
• Pegs
• Plumb bob
• Line Ranger
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24. Chains
Various types of chains used in surveying are
• Metric Chain
• Gunter‟s Chain or Surveyor‟s Chain
• Engineer‟s Chain
• Revenue Chain
• Steel Band or band chain
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25. Metric Chain • Metric chains are the most
commonly used chain in
India. These types of
chains comes in many
lengths such as 5, 10, 20
and 30 meters. Most
commonly used is 20m
chain.
• Tallies are provided at
every 2m of the chain for
quick reading. Every link of
this type of chain is 0.2m.
• The total length of the
chain is marked on the
brass handle at the ends.
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26. Gunter's Chain
• Gunter chain comes in standard
66ft. These chain consists of
100links, each link being 0.66ft or
7.92inches.
• The length 66ft is selected
because it is convenient in land
measurements.
10 square Gunter’s chains = 1 Acre
10 Gunter chains = 1 Furlong
80 Gunter chains = 1 mile
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27. • This chain comes in 100ft
length. Its consist of 100 links
each link being 1ft long. At
every 10 links a brass ring or
tags are provided for indication
of 10 links. Readings are taken
in feet and decimal.
Engineer’s Chain
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29. Revenue Chain
Revenue chain is 33 ft long
chain consisting of 16 links.
This chain is used for distance
measurements in feet &
inches for small areas.
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30. Steel Band or Band Chain
These types of chain consist of a
long narrow strip of steel of
uniform width of 12 to 16 mm and
thickness of 0.3 to 0.6 mm. this
chain is divides by brass studs at
every 20cm or instead of brass
studs, band chain may have
graduated engraving as
centimetre.
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31. Errors in chain Surveying
• Personal errors
• Compensating errors, and
• Cumulating errors.
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32. Compensating Errors
• These errors may be sometimes positive and sometimes
negative. Hence
• They are likely to get compensated when large number of
readings are taken. The magnitude of such errors can be
estimated by theory of probability.
The following are the examples of such errors:
1. Incorrect marking of the end of a chain.
2. Fractional part of chain may not be correct though total
length is corrected.
3. Graduations in tape may not be exactly same throughout.
4. In the method of stepping while measuring sloping
ground, plumbing may be crude.
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33. Cumulative Errors
• The errors that occur always in the same direction are called
cumulative errors. In each reading the error may be small,
but when large number of measurements are made they
may be considerable, since the error is always on one side.
Examples of such errors are:
• Bad ranging
• Bad straightening
• Erroneous length of chain
• Temperature variation
• Variation in applied pull
• Non-horizontality
• Sag in the chain, if suspended for measuring horizontal
distance on a sloping ground.
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34. Measuring Tapes
• Tapes are used for more accurate measurement. The
tapes are classified based on the materials of which they
are made of such as:
• Cloth or linen tape
• Fibre Tape
• Metallic Tape
• Steel tape
• Invar Tape
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35. Fibre Glass Tape Metallic Tape
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36. Steel Tape Invar Tape
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37. Other instruments details are
given in BCE Manual.
Please refer it.
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Prismatic compass Surveyors compass

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