Plane Table Surveying Reference From Surveying book (mahajan publication)

1. ARHAM VEERAYATAN INSTITUTE
OF ENGINEERING, TECHNOLOGY & RESEARCH
PRESENTED BY
KOTADIYA URVISH(150920106001)
KATHIRIYA VISHAL(15092010603)
VYAS KEYUR (150920106004)
PLANE TABLE SURVEYING
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2. TOPIC
1.Plane table surveying
2. Instrument for plane tabling
3. Advantages
4. Disadvantages
5. Principle of plane table survey
6. Method of setting up the plane table
7. Method of plane tabling
8.Error in plane tabling
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3. 1. Plane Table Surveying
 Plane Table Surveying is a graphical method of survey in which the field observations
and plotting are done simultaneously.
 It is simple and cheaper than theodolite survey. It is most suitable for small scale maps.
 The plan is drawn by the surveyor in the field, while the area to be surveyed is before his
eyes. Therefore, there is no possibility of omitting the necessary measurements.
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4. 2. Instrument for Plane Tabling
The following instruments are used in plane table surveying.
Equipments
I. Plane Table
II. Tripod
III. Alidade
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5. Continue……
Accessories
IV. Trough Compass
V. Spirit level
VI. U-Fork with Plumb bob
VII. Drawing paper
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6. I. Plane Table
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7. II. Tripod
 The plane table is mounted on a tripod
 The tripod is generally of open frame type, combined rigidity with lightness. The
tripod may be made to fold for convenience of transportation.
 Tripod is provided with three foot screws at its top for leveling of the plane
table.
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8. III. Alidade
 The alidade is useful for establishing a line of sight.
 Two Types of alidade are used.
 Simple alidade
 Telescopic alidade
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9. Simple Alidade
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10. Telescopic Alidade
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11. IV. Trough compass
Trough Compass
 The trough compass is required for drawing the line showing magnetic meridian
on the paper. It is used to orient the table to the magnetic meridian.
 When the freely suspended needle shows 00 at each end, a line is drawn on
the drawing paper which represents the magnetic north.
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12. Continue…..Trough Compass
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13. V. Spirit Level
 A Spirit Level is used for ascertaining If the
table is properly level.
 The Table is leveled by placing the level
on the board in two positions at right
angles and getting the bubble central in
both positions.
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14. VI. U-Fork With Plumb Bob
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15. VII. Drawing Paper
 Drawing paper is used for plotting the
ground details.
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16. 3. Advantages
 It is simple and cheaper than the theodolite survey.
 It is most suitable for small scale maps.
 No great skill is required to produce a satisfactory map and work may be
entrusted to a subordinate.
 It is useful in magnetic areas where compass may not be used.
 The mistakes in writing field books are eliminated.
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17. 4. Disadvantages
Disadvantages (Limitations)
 It is not intended for very accurate work.
 It is not suitable in monsoon.
 It is essentially a tropical instrument.
 Due to heaviness, it is inconvenient to transport.
 Since there are so many accessories, there is likelihood of them being lost.
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18. 5. Principle Of Plane Table Survey
 The principle of plane tabling is parallelism means,
 Principle: “All the rays drawn through various details should pass through
the survey station.”
 The Position of plane table at each station must be identical, i.e. at each survey
station the table must be oriented in the direction of magnetic north.
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19. 6. Method Of Setting Up The Plane
Table
 Three processes are involved in setting up the plane table over the station.
 Leveling
 Centering
 Orientation
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20. 7. Methods Of Plane Tabling
1. Radiation
2. Intersection
3. Traversing
4. Resection
 Special Methods of Resection
I. Compass Method
II. Back-ray Method
III. Two-point problem
IV. Three-point problem
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o The table should accurately centred.
o The rays should be accurately drawn through the station points.
o Table should be sufficiently clamped.
o The board should be horizontal.
o The objects should be accurately sighted.
8. Errors In Plane Tabling

22. Thank
you
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