�ݺ�ߣ

Engineering Surveying
1
Erbil Polytechnic University
Technical Engineering College
Civil Engineering Department
2022 - 2021
Practical
Principle of Surveying
Prepared by
Assistant Lecturer Mr. Kamal Y. Abdullah
Asst.Lecturer. Dilveen H. Omar
At. Prof. Salar Khudhur Husseinss

Syllabus (Main Content)
• Basic Principles
• Distance Measurement and Chain Surveying
• Distance Measuring Methods-Taping
1-direct methods
2-Indirect method
2

Two principles of measuring distance
1) It takes two points, to form a line.
2) The shortest distance between two points, is straight line.
4

Methods of Measuring Distance
5
1. Direct Methods of Measuring Distances
2. Indirect Methods of Measuring Distances

Indirect Methods of Measuring Distances
1-Theodolite instrument )Stadia(,
2-Tachometry
3-sub-tense method. The methods are Subtence bar,
4-Electronic distance mmeasurement (EDM)
5-Total Station, (TS)
6- G P S .
6

Electronic Distance Measurement (EDM)
7
accurately measure distance by measuring the time it takes
a laser or other ray to travel from the EDM to a prism and
back.

Electronic Distance Meters (EDM)
8

Surveying practical
Length and distance measurement
Observation & measurement
Methods of measuring Length and distances
1-direct methods
2-Indirect method
Direct methods)
)
1-pacing
2-measuring wheel
3-chain
4-tape
5-car odometer
9

Direct Methods of Measuring
Distances
• Pacing
• Measuring distance by counting
steps (paces).
• Distance is calculated by
multiplying the number of paces by
the individuals pace factor(usually
every step one meter ).
• Advantages
• Simple
• Low tech
• No specialized equipment
10
• Disadvantages
 Topography affects accuracy
 Requires practice to take a consistent pace.
 Must be able to traverse the distance..
• With practice, accuracy is about 2% of distance paced

Direct Methods of Measuring Distances
• Car Odometer
• measuring the distance passed over by any
wheeled vehicle
• An instrument attached to the wheel of a vehicle,
to measure the distance traversed.
11
Error 1% of distance

• An odometer wheel is a wheel
which uses an odometer to count
the rotations of the wheel. Use
for long rout distance like
(highway, railway )
12
• Advantages
– Easy to use
– Low tech
• Disadvantages
– Accuracy is influenced by surface
conditions.
– Must be able to traverse distance.
Error 1% of distance

The Chain is an old tool used in Land Surveying to measure
distance.
Error 0.2% of distance
13

Measuring tape
A tape measure or measuring tape is a flexible form of ruler. It
consists of a tape of( cloth, plastic, fiber glass, or metal strip) with
linear-measurement markings.
14

Distance Measuring Methods-Taping
15
• Advantages
– High precision
– accuracy
– Can be used to measure horizontal
distances.
• Disadvantages
– Multiple people
– Must have a clear, travelable route.
– High precision requires temperature and
tension correction.
Error 0.1% of distance.
Tape

Type of Tape
The following are the various types of tapes
Cloth tape
• Shrinkage with water
• Flexible with tension
• Do not broken under load
Metallic tape(Fiberglass)
• Less Shrinkage with water
• Less Flexible with tension
• Do not broken under load
16

Type of Tape
17
Invar Tapes: accurate tape made of steel (65%) & Nickel (35%)
but they
are very expensive
Easy broken .
Steel tape
• Easy broken
• High accuracy
• No effect by tension
• May caused injured skin

Tape Marking and Graduation
18

Equipment for Taping
• Pins
• are used to mark tape lengths.
• Most taping pins are made of steel
20

Equipments for Taping
• Range Pole (Range Rod)
• are used in taping applications for sighting
• points, marking ground points and for lining up surveyors
• red and white to make them more easily seen. Each band.
21

• Survey Pegs
• wooden (square or circular cross-section) & steel
• Use to mark point on the land
22

• Plumb Bob
• are typically made of brass. Bobs are used to get a
• “plumb” (straight) vertical line to a definite point,
typically
• bobs should be used for higher or greater heights.
23

• Level Ground
• Uniformly Sloping Ground
• Uneven Ground
Processes in taping Surveying
24

Level Ground
26
2-The distance greater than the tape length

Slope distance
28
This requires measurement also of either the
angle of inclination α
or the difference in elevation d.

Uneven Ground
• To measure horizontal distance with a tape , a level and
plumb bob must be used.
The tape is held level, horizontal, and the measurement at
the elevated end is transferred using a plumb bob.
• .
30

Slope correction…
31
For example :
s = 30.589 m
q = 2.5o
DH = 1.334 m
then
h = 30.589 cos(2.5)
h = 30.560 m
To calculate the horizontal distance :
h = s cosq or h = (s2 - DH2)1/2
q
horizontal distance = h
DH
Or….
s = 30.589 m
DH = 1.334 m
then
h = (30.5892 - 1.3342)1/2
h = 30.560 m

Step Taping…
32
required (horizontal) distance

Student Name :
Report Number. :
Report Name :
Date :
Mark :
34

Number
1- Report
2-Report Name( )
3-Group Name
4- Apparatus
5-Object
6-Procedure
7-Sketch
8-Table
9- Calculation
10-Discussion
35

Report ( )
1-Report Number ( 1 )
2-Report name-
Length and distance measurement .Perpendiculars off sets
Erecting and Dropping .
3-Object
A-B Are two fixed points to measure the horizontal distance
between these two point A and B .To Erecting
And Dropping lines for known point .
36

4-Apparatus
1-Tape(1)
2-Pin(10)
3-Range Pole(5)
4-Optical Square ( 1)
5-Plumb bob . (1)
5 September 2021 37

5-Procedure
•
1-Set two range poles vertically by means of plumb bob at points A and B
•
2-Ranging lines – setting the range pole in the line by eye then using the
optical prism.
•
6-Table-
38

• 7-sketch by Scale:
8-Calculation :
5 September 2021 39

Tape)
)
1-Steel Tape
2-Pocket Steel Tape
3-Rolling Tape
4-Digital Measuring Tape
5-Invar Tape
6-Linen tape (cloth)
7-Fiberglass tape
40

Erecting and dropping perpendiculars (or offsets):
• A- Erecting perpendiculars
• 1-Pythagoras
• 2-Length of Tape
3- Erecting by optical square
41

Pythagoras
Provided right-angle triangle (3-4-5) ratio to lay out XZ at 90
degrees to XY a twelve – unit tape would have knots tied at
unit positions 3 and 7 as shown in figure. One surveyor held
the three – unit knot at X the second surveyor held the seven –
unit knot at Y and the third surveyor holding both loose ends
of the tape. Stretched the tape tightly resulting in the location
of point Z.
These early surveyors knew that multiplies 3:4:5 e.g (6:8:10),
(30:40:50) would produce more accurate positioning.
•
42

3-optical square
43
a small hand instrument used by surveyors for laying off a right
angle by means of two mirrors set at an angle of 45 degrees

Dropping Perpendiculars
1-Radius .
2-Short length distance.
3-Dropping by optical square
44

Reference
Plan and Geodetic Surveying by late David Clark
Surveying By Frances H. Moffit
Surveying And Leveling by T.P. Kanetkar
Text Book Of Surveying by S. K. Hussain
Engineering Surveying (6th Edition) by Schofield W. & Breach M.
Surveying Principles and Application (6th Edition) by Barry F. Kavanagh.
45

�ݺ�ߣ

Basic Principles, Distance Measurement and Chain Surveying, Distance Measuring Methods-Taping

More Related Content

More from Bahzad5 (20)

Basic Principles, Distance Measurement and Chain Surveying, Distance Measuring Methods-Taping