SANKETIKA POLYTECHNIC COLLEGE | SURVEYING LAB MANUAL 1 DEPLOMA IN CIVIL ENGINEERING C-111 SURVEYING LAB MANUAL D.VINAYA ASST.PROFESSOR CIVIL ENGINEERING DEPARTMENT SANKETIKA POLYTECHNIC COLLEGE AFFILIATED TO STATE BOARD OF TECHNICAL EDUCATION & TRAINING, HYDERABAD
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SANKETIKA POLYTECHNIC COLLEGE | SURVEYING LAB MANUAL 1
DEPLOMA IN CIVIL ENGINEERING
C-111
SURVEYING LAB MANUAL
D.VINAYA ASST.PROFESSOR
CIVIL ENGINEERING DEPARTMENT
SANKETIKA POLYTECHNIC COLLEGE
AFFILIATED TO STATE BOARD OF TECHNICAL EDUCATION & TRAINING,
HYDERABAD
SANKETIKA POLYTECHNIC COLLEGE | SURVEYING LAB MANUAL 2
SURVEYING PRACTICALS-I
(Manual for first year Diploma in Civil Engineering for Polytechnic in Andhra Pradesh)
SANKETIKA POLYTECHNIC COLLEGE | SURVEYING LAB MANUAL 3
LIST OF EXPERIMENTS
CHAIN SURVEYING
STUDY OF INSTRUMENTS FOR CHAINING
PRACTISING UNFOLDING AND FOLDING OF A CHAIN
RANGING AND CHAINING OF LINES ON LEVEL GROUND AND RECORDING IN FIELD BOOK
CHAINING A LINE INVOLVING DIRECT AND INDIRECT RANGING
MEASUREMENTS OF LAND AREAS- CHAIN TRIANGULATION AND CROSS STAFF METHODS
CHAIN TRIANGULATION AROUND THE BUILDING COVERING A SMALL AREA WITH OVER
DETAILS, TAKING OFFSETS AND RECORDING
COMPASS SURVEYING
SETTING UP THE COMPASS-OBSERVATION OF BEARINGS-CALUATIONS OF INCLUDING
ANGLES
TRAVERSING WITH PRISMATIC COMPASS AND CHAIN-CLOSED TRAVERSE AND
RECORDING
TRAVERSING WITH PRISMATIC COMPASS AND CHAIN-OPEN TRAVERSE AND RECORDING
LEVELLING
STUDY OF DUMPY LEVEL, LEVELLING STAFF AND TEMPORARY ADJUSTMENTS OF LEVEL
TAKING LEVELS OF VARIOUS POINTS AND BOOKING THE SAME IN A LEVEL FIELD BOOK
DIFFERENTIAL OR FLY LEVELLING, REDUCING LEVELS BY HEIGHT OF COLLIMATION AND
RISE AND FALL METHOD
DIFFERENTIAL LEVELLING INVOLVING INVERTED LEVELS
RECIPROCAL LEVELLING
TAKING LEVELS OF LONGITUDINAL SECTION AND CROSS SECTIONS OF A ROAD/CANAL
PLOTTING
CONVENTIONAL SIGNS IN SURVEYING
PLOTTING OF PERPENDICULAR AND OBLIQUE OFFSETS
PLOTTING OF LAND SURVEYS-CHAIN AND CROSS STAFF SURVEY-CALCULATION OF
AREAS
PLOTTING OF CHAIN TRIANGULATION, SURVEYING OF SMALL AREAS AROUND BUILDING
PLOTTING OF CLOSED TRAVERSE-COMPASS SURVEYING LOCATION OF DETAILS AND
ADJUSTING ERROR BY BOW DITCHS METHOD
PLOTTING OF OPEN TRAVERSE BY COMPASS SURVEYING AND LOCATING DETAILS
PLOTTING OF L.C AND C.S
PLOTTING OF CONTOURS FROM RADIAL METHODS AND BLOCK LEVELLING
SANKETIKA POLYTECHNIC COLLEGE | SURVEYING LAB MANUAL 4
FAMILARITY WITH INSTRUMENTS USED IN CHAIN SURVEYING
OBJECTIVE:
Study of various instruments used in chain surveying and their
uses
INSTRUMENTS:
1) Chain or tape
2) Arrows
3) Ranging rods
4) Cross staff
5) Offset rods
6) Pegs
7) Plumb bob
DESCRIPTION OF INSTRUMENTS:
1 a) Chain:
The chain is composed of 100 or 150 pieces of galvanized mild
steel wire, 4mm in diameter called links .The ends of each link are bent into a
loop and connected together by means of three oval rings. The ends of the
chain are provided with handles for dragging the chain on the ground, each
wire with a swivel joint so that the chain can be turned without twisting. The
length of the chain is measured from the outside of one handle to the outside
of another handle.
Following are the various types of chain in common use:
1) Metric chains
SANKETIKA POLYTECHNIC COLLEGE | SURVEYING LAB MANUAL 5
2) Gunter` s chain or surveyors chain
3) Engineers chain
4) Revenue chain
5) Steel band or Band chain
Metric chain:
Metric chains are made in lengths 20m and 30m. Tallies are fixed at
Every five-meter length and brass rings are provided at every meter length
except where tallies are attached
b) Tapes:
The following are the various types of tapes
I) Cloth tape
ii) Metallic tape
SANKETIKA POLYTECHNIC COLLEGE | SURVEYING LAB MANUAL 6
iii) Steel tape
iv) Invar tape
Among the above, metallic tapes are
widely used in surveying. A metallic
tape is made of varnished strip of
waterproof line interwoven with small
brass, copper or bronze wires. These
are light in weight and flexible and are
made 2m, 5m 10m, 20m, 30m, and 50m.
2. Arrows:
Arrows are made of good quality hardened steel wire of 4 mm
diameter. The arrows are made 400 mm in length, are pointed at one and the
other end is bent into a loop or circle
SANKETIKA POLYTECHNIC COLLEGE | SURVEYING LAB MANUAL 7
3. Ranging rods:
Ranging rods are used to range some intermediate points in the
survey line the length of the ranging rod is either 2m or 3m. They are shod at
bottom with a heavy iron point. Ranging rods are divided into equal parts
0.2m long and they are painted alternately black and white or red and white
or red, white and black. When they are at considerable distance, red and white
or white and yellow flags about 25 cm square should be fastened at the top.
4. Cross staff:
The simplest instrument used for setting out a right
angle. The common forms of cross staff are:
SANKETIKA POLYTECHNIC COLLEGE | SURVEYING LAB MANUAL 8
SANKETIKA POLYTECHNIC COLLEGE | SURVEYING LAB MANUAL 9
5. OFFSET ROD:
The offset rod is used for measuring the off set of short lengths. It is
similar to a ranging rod and is usually of 3m lengths.
6. PEGS:
These are rods made from hard timber and tapered at one end, generally
25mm or 30mm square and 150mm long wooden pegs are used to mark the
position of the station on.
SANKETIKA POLYTECHNIC COLLEGE | SURVEYING LAB MANUAL 10
7. PLUMB BOB:
While chaining along sloping ground, a plumb bob is required
to transfer the points to the ground.
SANKETIKA POLYTECHNIC COLLEGE | SURVEYING LAB MANUAL 11
PRACTICING UNFOLDING AND FOLDING OF A CHAIN
AIM :
To learnt the technique of unfolding and folding of a metric chain.
INSTRUMENTS:
Metric chain
PROCEDURE:
UNFOLDING:
Remove the strap of the folded chain and take both the handles in the
left hand and hold the remaining portion of the chain in the right hand.
Holding both the handles in the left hand, throw the remaining portion
o f the chain in the forward direction on the ground.
Now the follower stands at the starting station by holding one handle
and directs the leader to move forward by holding the other handle
until the chain is fully stretched.
FOLDING:
Bring the two handles together on the ground by pulling the chain at
the center.
Commencing from the center two pairs of links are taken at a time with
the right hand and placed alternatively in both directions in the left
hand.
When the chain is completely folded the two brass handles will appear
at the top.
Now tie the chain with leather strap.
SANKETIKA POLYTECHNIC COLLEGE | SURVEYING LAB MANUAL 12
CHAINING A LINE BY DIRECT RANGING
AIM:
To measure the distance between two points on a level ground by
ranging.
NSTRUMENTS:
Chain 20m / 30m 1 No. Arrows 10 Nos.
Ranging rods 04 Nos. Pegs 2 Nos.
SANKETIKA POLYTECHNIC COLLEGE | SURVEYING LAB MANUAL 13
PROCEDURE:
Fix the ranging rods at the two given stations, where pegs are already
driven on the ground.
The follower stand behind station A and directs the leader, with ranging
rod to come in line with AB by signals of ranging
When the ranging rod comes in the line of AB the follower directs the
leader to fix the ranging rod in position.
Let the intermediate point be C which should be less than 20m / 30 m
Now the leader taken another ranging rod and stands between A and B
about 2/3 distance from A
The follower directs the leader to come in line of AB by using signals of
ranging.
As and when the point is located in the line of AB the follower instructs
to fix the ranging rod in position.
Let the other intermediate position be D which is less than 20 m / 30 m
from B
Now A, B, C and D are in one line. Now the leader and follower measure
the distance by measuring along A, C, D, B.
RESULT:
The distance between AB = __________ meter.
FIELD APPLICATION:
» It can be extended to measure the lengths of more than two chain lengths.
» By measuring the boundaries of given traverse the areas can be calculated.
» The features can be located either by measuring oblique or perpendicular
offset from the chain line.
2.CHAINING A LINE BY INDIRECT RANGING
SANKETIKA POLYTECHNIC COLLEGE | SURVEYING LAB MANUAL 14
AIM:
Chaining a line when a hill or high ground intervenes preventing
Intervisibility of ends of line.
INSTRUMENTS:
Chain 20m / 30m 1 No. Arrows 10 Nos.
Ranging rods 04 Nos.
PROCEDURE:
SANKETIKA POLYTECHNIC COLLEGE | SURVEYING LAB MANUAL 15
Fix the two ranging rods at the given stations A and B which are not
intervisible due to raising ground.
Select two intermediate points M1 and N1 such that from each point
both A and B are visible.
The person at M1 directs the person at N1 to move to a new position N2
in line with M1B.
The person at N2 then directs the person at M1 to move to a new
position M2 in line with N2A.
The person at M2 directs the person at N2 to a new position N3 in line
with M2B.
The person at N3 directs the person at M2 to a new position M3 in line
with N3A.
The process is repeated till the points M and N are located in such a way
that M finds the person at N in line with AB and the person at N finds the
person at M in line with AB.
» After fixing the points M and N, other points are also fixed by direct
ranging and the length of the line is measured.
Result:
Length of AM = ____ meter.
Length of MN = ____ meter.
Length of NB = ____ meter.
Therefore distance of AB = distance AM + distance MN + distance NB
SANKETIKA POLYTECHNIC COLLEGE | SURVEYING LAB MANUAL 16
MEASUREMENT OF AREA BY CHAIN TRIANGULATION
AIM:
To measure the area of the given field by chain triangulation
INSTRUMENTS:
Chain 20m / 30m 1 No.
Arrows 10 Nos.
Ranging rods 6 Nos.
Pegs 5 Nos.
PROCEDURE:
Let ABCDE be the given field whose area is to be measured, fix the pegs
at A, B, C, D & E.
Divide area into three triangles ADE, ABD and BCD by joining AD and
BD.
SANKETIKA POLYTECHNIC COLLEGE | SURVEYING LAB MANUAL 17
Measure the lengths AB, BC , CD, DE, EA, AD and BD.
Calculate the area of the triangles.
The sum of the areas of the three triangles is the area of the given field.
FORMULA:
Area of the triangle ∆ = √ s (s-a) (s-b) (s-c)
Where S = (a + b+ c) / 2
a, b, c, are the sides of the triangles
RESULT:
The area of the given field = _______ Square meter.
SANKETIKA POLYTECHNIC COLLEGE | SURVEYING LAB MANUAL 18
CHAIN TRIANGULATION AROUND A BUILDING
OBJECTIVE:
To chain around the building to cover small area by chain
triangulation
INSTRUMENTS:
Chain 20m / 30m 1 No.
Arrows 10 Nos.
Ranging rods 4 Nos.
Pegs 4 Nos.
Tape 20m/30m 1 No
Cross staff 1No
PROCEDURE:
Select three survey stations A, B and C such that from each survey
station the other two Stations are visible..
Fix the ranging rods at A, B and C
Fix the intermediate stations along the chain line AB, BC and CA by
ranging.
SANKETIKA POLYTECHNIC COLLEGE | SURVEYING LAB MANUAL 19
Measure the offsets of the corners of the building either perpendicular
or oblique.
Each point requires two measurements from two definite reference
points on the same line or from two adjacent chain lines.
Measure the points which are very far away from the main chain lines
from tie line i.e. , the corners points of building R and S. Measure the
check line CD.
RESULT:
From the recorded measurements of the building area is plotted.
NOTE:
The student should prepare a layout of the given area covering building
roads etc.
SANKETIKA POLYTECHNIC COLLEGE | SURVEYING LAB MANUAL 20
CHAINING ACROSS OBSTACLES
AIM:-
To measure distance between two points by chaining across
different types of Obstacles encountered by indirect method.
APPARATUS:-
Chain, tape, cross-staff, ranging rods, arrows.
PROCEDURE:-
Obstacles to chaining prevent chainmen to measuring directly
between Two points And give rise to a set of problems in which distances are
found by indirect Measurements.
OBSTACLES TO CHAINING ARE OF THREE KINDS.
A. Obstacles to ranging but not chaining Ex :- (High level ground)
B. Obstacles to chaining but not ranging Ex :- (Pond, river)
C. Obstacles to both chaining and ranging Ex:-(building)
A) OBSTACLES TO RANGING BUT NOT CHAINING:-
This type of problem comes, when a rising ground or a forest area
interrupts the chain line. The end station are not inter visible
There may two cases of this obstacle.
1. Both ends of line may be visible from intermediate points on line.
2. Both ends of line may not be visible from intermediate points on line.
Case-1:-
Both the stations are visible from intermediate points on the line
In this case reciprocal ranging is adopted and chaining is done by
stepping method
SANKETIKA POLYTECHNIC COLLEGE | SURVEYING LAB MANUAL 21
A and B are two end stations, which are not inter visible due to a hill in
between them.
Select two intermediate points Pl and Ql, such that from each station
point A and B are visible.
Two persons take up the positions Pl and Ql with ranging rods.
First the person standing at Pl directs the person at Ql to come in line of
Pl B, and his new position will be Q2.
Now, the person standing at Q2, directs the person at pi, to come in line
of Q2 A, and his new position will be P2.
7. Now, the person standing at P2, directs the person at Q2, to come in
line of P2 B, and his new position will be Q3.
This process is continued until the intermediate points P and Q are
located in such a way that the person standing at P, see Q and B in the
line, and the person standing at Q, see P and A in the line.
Distance AB = AP+PQ+QB
Case-2:-
The end stations are not visible from the intermediate points on the line:
SANKETIKA POLYTECHNIC COLLEGE | SURVEYING LAB MANUAL 22
This is the case when trees ,bushes or jungle comes across the chain line
In this case the method of random line is most suitable
In fig let PQ be the line in which P and Q are not visible from
intermediate Point on it.
Through P draw a random line PQ in any convenient direction but as
nearly to Towards Q as possible.
The points Q should be so chosen that, Q1 is visible from Q and Q,Q1 is
in random Line.
Measure QQ1 select points S1 and R1 on random line and erect
perpendicular SS1 and RR1 on it. Make
SS1= PS1/PQ1 x QQ1 and
RR1= PR1/PQ1 x QQ1
Join SR and prolong.
B) OBSTACLES TO CHAINING BUT NOT RANGING:-
There may be two cases of this obstacle.
1. When it is possible to chain round the obstacle. i.e. A POND.
2. When it is not possible to chain round the obstacle. i.e. A RIVER.
SANKETIKA POLYTECHNIC COLLEGE | SURVEYING LAB MANUAL 23
CASE (1): - Following are the methods.
Method (a):-
1. Select two points A AND B on either side.
2. Set out equal perpendicular AC and BD as shown in fig (a)
3. Measure CD=AB.
Method (b):-
set out AC perpendicular to chain line as shown in fig (b)
Measure AC and BC
The length AB is calculated from the relation
AB=√BC²-AC²
SANKETIKA POLYTECHNIC COLLEGE | SURVEYING LAB MANUAL 24
Method (c):-
By cross staff find a point C .which subtends 90° with A and B as Shown
in fig (C). AC and BC.
The length AB is calculated from relation AB= √AC²+BC².
Method D:
Select any point E and range C in line with AE, making AE =EC
2. Range D in line with BE and make BE=ED as shown in fig (d).
3. Measure CD then AB=CD.
CASE (2): - Following are the methods.
Method (a):-
Select point B on one side and A and C on the other side.
Erect AD and CE as perpendicular to AB and range B,D and E in One line
as shown in fig (e).
Measure AC, AD and CE.
SANKETIKA POLYTECHNIC COLLEGE | SURVEYING LAB MANUAL 25
If a line DF is drawn parallel to AB cutting CE in F perpendicularly
The triangle ABD and FDE will be similar.
Method (b):
Locate a point R in such a way that it makes 900 with PQ.
Range S in line with PR and make PS = PR.
At S erect a perpendicular ST to cut the line AB at T.
Then PQ =PT
C) OBSTACLES TO BOTH CHAINING AND RANGING:-
A Building is the typical example of this type of obstacles. The problem lies
in prolonging the line beyond the obstacle and determine the distance across
it
Method (a):-
Choose two points A and B to one side erect perpendicular AC and BD of
equal length.
SANKETIKA POLYTECHNIC COLLEGE | SURVEYING LAB MANUAL 26
Join CD and prolong It pass the obstacles.
Choose two points E and F on CD and erect perpendicular EG and FH
equal to AC or BD as shown in fig (g).
Join GH and prolong it. Measure DE.
5) BG=DE.
Method (b):-
Select a point A and erect a perpendicular AC of any convenient Length.
Select another point B on chain line such that AB=AC.
Join B and C and prolong it. To any convenient point D.
At D set a right angle DE such that DE=DB.
Choose another point F on DE such that DF=DC with F as centre and AB
as radius. Draw an arc with E as center draw another arc of same
Radius to cut previous arc in G
Join GE which will be in range with chain line. Refer the fig (h)
Measure CF then AG=CF.
SANKETIKA POLYTECHNIC COLLEGE | SURVEYING LAB MANUAL 27
VIVA QUESTIONS
1) What is meant by surveying?
2) What are the principles of surveying?
3) How many links are provided in a 20-meter metric chain?
4) Differentiate between ranging rod and offset rod.
5) Define the terms base line tie line and check line.
6) When the reciprocal ranging is adopted.
7) What is meant by perpendicular and oblique offset?
8) What are the instruments required for erecting perpendicular offset.
9) What is meant by survey station?
10) What is meant by ranging?
SANKETIKA POLYTECHNIC COLLEGE | SURVEYING LAB MANUAL 28
Compass surveying recommended when:-
A large area to be surveyed
The course of a river (or) coast line is to be surveyed
The area is crowded with many details and triangulation is not possible
TYPES OF COMPASS:
There are two types of compass
1. Prismatic Compass (0 to 360 Degrees)
2. Surveyor’s Compass (0 to 90 Degrees)
1. Compass Box 2. Magnetic Needle
SANKETIKA POLYTECHNIC COLLEGE | SURVEYING LAB MANUAL 29
3. Graduated Ring 4. Pivot
5. Objective Vane 6. Eye Vane
7. Adjustable Mirror 8. Spring Brake
9. Brake Pin 10. Lifting Lever
11. Lifting Pin 12. Prism
13. Focusing Stud 14. Glass Cover
15. Prism Dust Cap 16. Sun Glasses
DESCRIPTION OF INSTRUMENTS
COMPASS BOX:
It is a circular box of diameter 85 to 110 mm having pivot at
the center and covered with plain glass at top.
MAGNETIC NEEDLE:
It facilitates in taking the bearings of survey lines with reference
to the magnetic north.
GRADUATED RING:
The bearings are marked inverted on the graduated
Rings from 0° to 360° in a clockwise starting 0° from south
PIVOT:
Magnet is freely held with this.
OBJECT VANE:
It consists of prism with a sighting slit at the top. The prism
magnifies and erects the inverted graduations.
SANKETIKA POLYTECHNIC COLLEGE | SURVEYING LAB MANUAL 30
BRAKE PIN:
It is pressed to stop the oscillations of the graduated ring.
LIFTING PIN:
On pressing it brings the lifting lever into action.
COLOUR GLASSES:
Red and blue glasses are provided with the prism to
Sight luminous objects
Parts of Prismatic Compass
Compass Box:
1. Circular 8 to 10 cm (80mm to 100mm) metallic
2. At the center of box pivot is provided.
Magnetic Needle and Graduated Ring:
1. On pivot the magnetic needle rests
2. Aluminum graduated ring is attached to needle
3. Graduated ring has 0 degree to 360 degrees clockwise
4. i.e. 00 at south, 900 at west, 1800 at north, 2700 at east
5. Least count is 30minutes
SANKETIKA POLYTECHNIC COLLEGE | SURVEYING LAB MANUAL 31
Sight Vane and Object Vane Of Compass:
These are fixed diametrically opposite to the each other.
Object vane consists of vertical hair attached to the frame
Sight vane (or eye slit) consists of vertical slit cut into upper assembly of
the prism unit
prism unit is hinged to the box
Adjustments of Prismatic Compass
Fixing the compass with tripod stand.
Centering
Leveling
Adjustment of prism
Observation of bearing
Bearings are designated by two systems
Whole Circle Bearing (WCB )
Quadrantal Bearing / or reduced bearings( QB / RB )
Whole circle bearing (W.C.B.) :
The bearing of a line measured from the north in clockwise direction.
The value of WCB may vary from 00 to 3600
SANKETIKA POLYTECHNIC COLLEGE | SURVEYING LAB MANUAL 32
SANKETIKA POLYTECHNIC COLLEGE | SURVEYING LAB MANUAL 33
SANKETIKA POLYTECHNIC COLLEGE | SURVEYING LAB MANUAL 34
3. DETERMINATION OF DISTANCE BETWEEN TWO INACCESSIBLE
POINTS WITH COMPASS
AIM:-
TO determine distance between two inaccessible points with