This document provides information on traversing and the tools used for traversing surveys. It discusses the components of a traverse including bearing, length of lines, latitude and departure. It also outlines the apparatus used for traversing including theodolites, tripods, rods and plummets. The document covers open and closed traverses, types of traverses such as loop and connecting traverses. It provides details on traverse computation steps such as balancing angles, determining bearings, checking for errors and adjusting for misclosures.
Plane and Applied Surveying 2
Traversing Theory Part
Traverse Computations
Definition
Types of Meridian
Applications of traversing
Bearings
Correction for observed angles (closed traverse)
Check angular Misclosure
Adjust angular Misclosure
Calculate adjusted bearings
Compute (E, N) for each traverse line
Coordinates.
-Traversing
Methods of conducting Traverse
1. Theodolite
2. Total Station
2. Compass
3. GPS
Bearings
Bearings
Bearing is the angle which a certain line make with a
certain meridian. Bearing with respect to true meridian is
called true bearings while magnetic bearing is the angle
which a line makes with respect to magnetic meridian.
There are two ways to represent the bearings,
Fore and back bearings
Whole circle bearing (W.C.B) ,(Azimuth)
Reduced Bearing (R.B) or quadrant bearing
6 The bearing of a line measured in the forward direction of survey line is called the ‘Fore Bearing’ (FB) of that line.
The bearing of the line measured in the direction opposite to the direction
of the progress of survey is called the ‘Back Bearing’ (BB) of the line.
BB= FB ± 180°
+ sign is applied when FB is < 180°
- sign is applied when FB is > 180°
1) Whole Circle Bearing (W.C.B) (Azimuth)
Is the bearing always measured from north in clockwise direction to a point.
Whole Circle Bearing (W.C.B) (Azimuth)
2) Reduced Bearing
Reduced bearing or Quadrant bearing is the angle which a line
makes from North or South Pole whichever may be near. The value of angle is from 0° to 90° , and are taken either clock wisely or anti clock wisely.
-Quadrant bearing
The difference between the whole circle bearing and quadrant
bearing are as follows.
-Example The following fore bearings were observed for lines, AB, BC, CD, and DE Determine their back bearings: • 145°, 285°, 65°, 215°
Example The Fore Bearing of the following lines are given Find the
Back Bearing.
(a) FB of AB= 310° 30’
(b) FB of BC= 145° 15’
(c) FB of CD = 210° 30’
(d) FB of DE = 60° 45’
Example:
Convert the following whole circle bearing to quadrant or
reduced bearings :
( i ) 42ᵒ 30’ ( ii ) 126ᵒ 15’
( iii ) 242ᵒ 45’ ( iv ) 328ᵒ10’
Example
Convert the following reduced bearings to whole circle
bearings:
( I ) N 65ᵒ 12’ E ( ii ) S 36ᵒ 48’ E
( iii ) S 38ᵒ 18’ W ( iv ) N 26ᵒ 32’ W
Closed Traverse
• Ends at a known point with known direction Geometrical Constraints
-Adjust the deflection angles
2-Interior angles Traverse
Interior angles are measured clockwise or counterclockwise between two adjacent lines on the inside of a closed polygon figure.
Example
The following traverse have five sides with five internal
angles. Find the angular misclosure and apply the angle
correction
-3-Exterior angle Traverse
Correction for observed angles (closed traverse)
Example:
IF ∑observed angles for traverse (ABCDA)= 360˚00′ 48″ find misclosure and correct the interior angles. Check Allowable Angle Misclosure
Prepared by:Asst. Prof. Salar K.Hussein
Erbil Polytechnic University
Plane and Applied Surveying 2
Traversing Theory Part
Traverse Computations
Definition
Types of Meridian
Applications of traversing
Bearings
Correction for observed angles (closed traverse)
Check angular Misclosure
Adjust angular Misclosure
Calculate adjusted bearings
Compute (E, N) for each traverse line
Coordinates.
-Traversing
Methods of conducting Traverse
1. Theodolite
2. Total Station
2. Compass
3. GPS
Bearings
Bearings
Bearing is the angle which a certain line make with a
certain meridian. Bearing with respect to true meridian is
called true bearings while magnetic bearing is the angle
which a line makes with respect to magnetic meridian.
There are two ways to represent the bearings,
Fore and back bearings
Whole circle bearing (W.C.B) ,(Azimuth)
Reduced Bearing (R.B) or quadrant bearing
6 The bearing of a line measured in the forward direction of survey line is called the ‘Fore Bearing’ (FB) of that line.
The bearing of the line measured in the direction opposite to the direction
of the progress of survey is called the ‘Back Bearing’ (BB) of the line.
BB= FB ± 180°
+ sign is applied when FB is < 180°
- sign is applied when FB is > 180°
1) Whole Circle Bearing (W.C.B) (Azimuth)
Is the bearing always measured from north in clockwise direction to a point.
Whole Circle Bearing (W.C.B) (Azimuth)
2) Reduced Bearing
Reduced bearing or Quadrant bearing is the angle which a line
makes from North or South Pole whichever may be near. The value of angle is from 0° to 90° , and are taken either clock wisely or anti clock wisely.
-Quadrant bearing
The difference between the whole circle bearing and quadrant
bearing are as follows.
-Example The following fore bearings were observed for lines, AB, BC, CD, and DE Determine their back bearings: • 145°, 285°, 65°, 215°
Example The Fore Bearing of the following lines are given Find the
Back Bearing.
(a) FB of AB= 310° 30’
(b) FB of BC= 145° 15’
(c) FB of CD = 210° 30’
(d) FB of DE = 60° 45’
Example:
Convert the following whole circle bearing to quadrant or
reduced bearings :
( i ) 42ᵒ 30’ ( ii ) 126ᵒ 15’
( iii ) 242ᵒ 45’ ( iv ) 328ᵒ10’
Example
Convert the following reduced bearings to whole circle
bearings:
( I ) N 65ᵒ 12’ E ( ii ) S 36ᵒ 48’ E
( iii ) S 38ᵒ 18’ W ( iv ) N 26ᵒ 32’ W
Closed Traverse
• Ends at a known point with known direction Geometrical Constraints
-Adjust the deflection angles
2-Interior angles Traverse
Interior angles are measured clockwise or counterclockwise between two adjacent lines on the inside of a closed polygon figure.
Example
The following traverse have five sides with five internal
angles. Find the angular misclosure and apply the angle
correction
-3-Exterior angle Traverse
Correction for observed angles (closed traverse)
Example:
IF ∑observed angles for traverse (ABCDA)= 360˚00′ 48″ find misclosure and correct the interior angles. Check Allowable Angle Misclosure
Prepared by:Asst. Prof. Salar K.Hussein
Erbil Polytechnic University
The moment distribution method is a structural analysis method for statically indeterminate beams and frames developed by Hardy Cross. It was published in 1930 in an ASCE journal.[1] The method only accounts for flexural effects and ignores axial and shear effects. From the 1930s until computers began to be widely used in the design and analysis of structures, the moment distribution method was the most widely practiced method.
Avaliação do comportamento de vigas de concreto armado e vigas mistas de aço ...Bruno Calheiros Kikuchi
As vigas, que são elementos lineares destinados a vencer vãos e transmitir as ações nelas atuantes para os apoios, apresentam um bom desempenho à flexão simples, sejam de concreto armado ou mista de aço e concreto. Isso ocorre quando o concreto trabalha à compressão e o aço, à tração, de modo que um material complemente o outro, aproveitando ao máximo as vantagens de cada um. Contudo, o funcionamento conjunto entre aço e concreto apresenta um comportamento estrutural bastante complexo devido, entre vários fatores, à significativa diferença entre as resistências à tração e à compressão do concreto; à não linearidade da relação tensão-deformação do concreto já para níveis de tensão relativamente baixos; à aderência imperfeita entre o aço e o concreto adjacente; à fissuração do concreto e à transmissão de esforços através das fissuras. Dessa maneira, surge a importância do desenvolvimento de modelos numéricos que permitam simular de maneira realística o comportamento desses elementos quando submetido a variados estágios de solicitação. O objetivo principal deste trabalho é a avaliação do comportamento de vigas de concreto armado e vigas mistas de aço e concreto, por meio de simulação numérica baseada no Método dos Elementos Finitos. Os modelos numéricos foram desenvolvidos no programa computacional Abaqus, utilizando-se análise não linear e o modelo de plasticidade com dano para o concreto. Os resultados obtidos evidenciam a capacidade dos modelos representaram o comportamento estrutural das vigas, uma vez que apresentaram proximidade entre as cargas de colapso e um comportamento geral muito condizente com os resultados experimentais encontrados na literatura.
surveying Engineering
Fly Levelling
Fly leveling: -Fly leveling is just like differential leveling carried
out to check the accuracy of leveling work. It is a very approximate
form of leveling in which sights are taken as large as possible. in this
method, a line of levels is run to determine approximately reduced
levels of the points carried out with more rapidly and less precision
The aim of fly Levelling: The main purpose of this type of leveling is
to check the values of the reduced levels of the bench marks already
fixed. In this method only back sight and foresight are taken. There is no need of intermediate sights. However great care has to be taken for selecting the change points (Turning Points) and for taking reading on the change points because the accuracy of leveling depends upon these
-Create Bench Marks (BM).
Bench Marks
Bench Mark is a point of known elevation, there are three Type of Bench Marks
1-Perment Bench Mark.
2-Orbitrary Bench Mark .
3-Temporary Bench Mark .
-Leveling Process Calculation.
1. Height of collimation method
2. Rise and Fall method
How do we find horizontal distance using levelling Machine.
Fly Levelling Close loop survey.
Fly and Differential leveling Using (Rise & fall) and (HI)methods.
*Checks for Errors
-Misclosure
Allowable closing error
Where:
D =Distance in km
E = Misclosure error in (mm).
C = 30 for fixed levelling process in rough ground.
C = 15 for normal leveling in flat area (Good work)
Fly Levelling example
Computation of Elevations for an open loop survey H.I method
Computation of Elevations
Differential Leveling
Computation of Elevations
-Correction For Errors in Leveling
1. Errors Due to the line of sight being not horizontal
2. Error Due to Curvature and refraction.
Errors in differential leveling: -
1) Non adjustment of the instrument: -
a) Adjustment of cross-wire ring
b) Adjustment of the bubble tube
c) Adjustment of line of sight
2-Errors in levelling
• Collimation line
• Parallax
• Change point instability
• Instrument instability
• Benchmark instability
• Staff reading errors , • Staff verticality • Level Instrument shading • Temperature on staff • Booking errors) • Earth curvature • Refraction • The Bubble not center.
3-Constant error (instrumental error):
A. Non vertically of the staff.
B. Collimation error in the instrument.
C. Staff gradation error.
4- Random error (natural error):
A. Effect of wind and temperature.
B. Soft and hard ground.
C. Change points. CP
D. Human deficiencies and neglect
Prepared by:
Asst. Prof. Salar K.Hussein
Mr. Kamal Y.Abdullah
Asst.Lecturer. Dilveen H. Omar
Erbil Polytechnic University
Technical Engineering College
Civil Engineering Department
The moment distribution method is a structural analysis method for statically indeterminate beams and frames developed by Hardy Cross. It was published in 1930 in an ASCE journal.[1] The method only accounts for flexural effects and ignores axial and shear effects. From the 1930s until computers began to be widely used in the design and analysis of structures, the moment distribution method was the most widely practiced method.
Avaliação do comportamento de vigas de concreto armado e vigas mistas de aço ...Bruno Calheiros Kikuchi
As vigas, que são elementos lineares destinados a vencer vãos e transmitir as ações nelas atuantes para os apoios, apresentam um bom desempenho à flexão simples, sejam de concreto armado ou mista de aço e concreto. Isso ocorre quando o concreto trabalha à compressão e o aço, à tração, de modo que um material complemente o outro, aproveitando ao máximo as vantagens de cada um. Contudo, o funcionamento conjunto entre aço e concreto apresenta um comportamento estrutural bastante complexo devido, entre vários fatores, à significativa diferença entre as resistências à tração e à compressão do concreto; à não linearidade da relação tensão-deformação do concreto já para níveis de tensão relativamente baixos; à aderência imperfeita entre o aço e o concreto adjacente; à fissuração do concreto e à transmissão de esforços através das fissuras. Dessa maneira, surge a importância do desenvolvimento de modelos numéricos que permitam simular de maneira realística o comportamento desses elementos quando submetido a variados estágios de solicitação. O objetivo principal deste trabalho é a avaliação do comportamento de vigas de concreto armado e vigas mistas de aço e concreto, por meio de simulação numérica baseada no Método dos Elementos Finitos. Os modelos numéricos foram desenvolvidos no programa computacional Abaqus, utilizando-se análise não linear e o modelo de plasticidade com dano para o concreto. Os resultados obtidos evidenciam a capacidade dos modelos representaram o comportamento estrutural das vigas, uma vez que apresentaram proximidade entre as cargas de colapso e um comportamento geral muito condizente com os resultados experimentais encontrados na literatura.
surveying Engineering
Fly Levelling
Fly leveling: -Fly leveling is just like differential leveling carried
out to check the accuracy of leveling work. It is a very approximate
form of leveling in which sights are taken as large as possible. in this
method, a line of levels is run to determine approximately reduced
levels of the points carried out with more rapidly and less precision
The aim of fly Levelling: The main purpose of this type of leveling is
to check the values of the reduced levels of the bench marks already
fixed. In this method only back sight and foresight are taken. There is no need of intermediate sights. However great care has to be taken for selecting the change points (Turning Points) and for taking reading on the change points because the accuracy of leveling depends upon these
-Create Bench Marks (BM).
Bench Marks
Bench Mark is a point of known elevation, there are three Type of Bench Marks
1-Perment Bench Mark.
2-Orbitrary Bench Mark .
3-Temporary Bench Mark .
-Leveling Process Calculation.
1. Height of collimation method
2. Rise and Fall method
How do we find horizontal distance using levelling Machine.
Fly Levelling Close loop survey.
Fly and Differential leveling Using (Rise & fall) and (HI)methods.
*Checks for Errors
-Misclosure
Allowable closing error
Where:
D =Distance in km
E = Misclosure error in (mm).
C = 30 for fixed levelling process in rough ground.
C = 15 for normal leveling in flat area (Good work)
Fly Levelling example
Computation of Elevations for an open loop survey H.I method
Computation of Elevations
Differential Leveling
Computation of Elevations
-Correction For Errors in Leveling
1. Errors Due to the line of sight being not horizontal
2. Error Due to Curvature and refraction.
Errors in differential leveling: -
1) Non adjustment of the instrument: -
a) Adjustment of cross-wire ring
b) Adjustment of the bubble tube
c) Adjustment of line of sight
2-Errors in levelling
• Collimation line
• Parallax
• Change point instability
• Instrument instability
• Benchmark instability
• Staff reading errors , • Staff verticality • Level Instrument shading • Temperature on staff • Booking errors) • Earth curvature • Refraction • The Bubble not center.
3-Constant error (instrumental error):
A. Non vertically of the staff.
B. Collimation error in the instrument.
C. Staff gradation error.
4- Random error (natural error):
A. Effect of wind and temperature.
B. Soft and hard ground.
C. Change points. CP
D. Human deficiencies and neglect
Prepared by:
Asst. Prof. Salar K.Hussein
Mr. Kamal Y.Abdullah
Asst.Lecturer. Dilveen H. Omar
Erbil Polytechnic University
Technical Engineering College
Civil Engineering Department
TOTAL STATION: THEORY, USES AND APPLICATIONS. Ahmed Nassar
TOTAL STATION: THEORY, USES AND APPLICATIONS.
The total station, (also known as electronic tacheometer) is an instrument that can measure horizontal and vertical angles together with slope distance and can be considered as combined EDM plus electronic theodolite. In common with other electronic surveying equipment, total stations are operated using a multi-function keyboard which is connected to a microprocessor built into the instrument. The microprocessor not only controls both the angle and distance measuring systems but is also used as a small computer that can calculate slope corrections, vertical components, rectangular coordinates and, in some cases, can also store observations directly using an internal memory. Nowadays surveying systems are available which can be use in an integrated manner with Global Positioning System (GPS). so, future total stations may have integrated GPS receivers as part of the measurement unit.
Report Assignment 2 for Site Surveying module which requires us to do Traversing measurement around the campus carpark, for the Bachelor of Quantity Surveying (BQS) Course Semester 2, Taylor's University Lakeside Campus
Traversing Notes |surveying II | Sudip khadka Sudip khadka
Traverse is a method in the field of surveying to establish control networks. It is also used in geodesy. Traverse networks involve placing survey stations along a line or path of travel, and then using the previously surveyed points as a base for observing the next point
Model Attribute Check Company Auto PropertyCeline George
In Odoo, the multi-company feature allows you to manage multiple companies within a single Odoo database instance. Each company can have its own configurations while still sharing common resources such as products, customers, and suppliers.
Instructions for Submissions thorugh G- Classroom.pptxJheel Barad
This presentation provides a briefing on how to upload submissions and documents in Google Classroom. It was prepared as part of an orientation for new Sainik School in-service teacher trainees. As a training officer, my goal is to ensure that you are comfortable and proficient with this essential tool for managing assignments and fostering student engagement.
Francesca Gottschalk - How can education support child empowerment.pptxEduSkills OECD
Francesca Gottschalk from the OECD’s Centre for Educational Research and Innovation presents at the Ask an Expert Webinar: How can education support child empowerment?
Welcome to TechSoup New Member Orientation and Q&A (May 2024).pdfTechSoup
In this webinar you will learn how your organization can access TechSoup's wide variety of product discount and donation programs. From hardware to software, we'll give you a tour of the tools available to help your nonprofit with productivity, collaboration, financial management, donor tracking, security, and more.
The French Revolution, which began in 1789, was a period of radical social and political upheaval in France. It marked the decline of absolute monarchies, the rise of secular and democratic republics, and the eventual rise of Napoleon Bonaparte. This revolutionary period is crucial in understanding the transition from feudalism to modernity in Europe.
For more information, visit-www.vavaclasses.com
1. 1 | P a g e
SCHOOL OF ARCHITECTURE, BUILDING AND DESIGN
BACHELOR OF QUANTITY SURVEYING (HONS)
SITE SURVEYING (QSB 60103)
SEMESTER 2
FIELDWORK 2 : TRAVERSING
NAME STUDENT ID
TANG LAM YU 0324966
TEE WAN NEE 0325074
TEO CHIANG LOONG 0323762
WONG SHER SHENG 0329950
YAP CHOE HOONG 0323161
2. 2 | P a g e
CONTENT
NO CONTENT PAGE
COVER PAGE 1
TABLE OF CONTENT 2
1.1 INTRODUCTION TO TRAVERSING 3-13
1.1 Traversing
1.2 Purposes of Traverse Survey
1.3 Advantages of Traversing
1.4 Tools Used
1.5 Types of Traverse
1.6 Components Of Traverse
1.7 Traverse Computation
2.0 OUTLINE APPARATUS 14 - 21
2.1 Theodolite
2.2 Adjustable Leg Tripod
2.3 Levelling Rod/ Levelling Staff
2.4 Optical Plummet
2.5 Bull’s Eyes Level ( Spirit Bubble )
2.6 Ranging Rod
2.7 Plumb Bob
3.0 OBJECTIVE 22
4.0 FIELDWORK 23 – 34
4.1 Field Data
4.2 Field Average Data
4.3 Field Data – angles
4.4 Angular Error & Angle Adjustment
4.5 Adjusted Data
4.6 Course Bearing & Azimuth
4.7 Stadia Method (Distance/ Length)
4.8 Latitude & Departure
4.9 Coordinates
4.10 Area Of Traverse
5.0 GROUP PHOTO 35
6.0 CONCLUSION 36
3. 3 | P a g e
1.1Traversing
Traversing is a method to establish horizontal control network. It is also used in geodetic
work. Traverse networks involved placing the survey stations along a line or path of travel,
and then using the previously surveyed points as a base for observing the next point. Not
only that, traversing also consists of a series of line connecting successive points whose
lengths and directions have been determined from field measurement. Precise traverse
surveys are much more practical these days with the aid of Electronic Distance
Measurement (EDM) device.
1.2 Purposes of Traverse Survey
Traverse surveys are made for many purposes which includes:
Determining the position of existing boundary markers.
Establish the position of boundary lines.
Determine the position of arbitrary points which data may be obtained for preparing
various types of maps
Establish ground control for photographic mapping
Establish control for gathering data regarding Earthwork quantities in railroad
highway, utility and other construction work
1.3 Advantages of Traversing
Traverse network has many ADVANTAGES compared to other system, including:-
This system can change to any shape and can accommodate to a great deal of
different terrains
Only a few observations need to be taken at each station (other survey networks
require a great deal of angular and linear observations)
Free of strength of figure considerations that happen in triangular systems.
Scale error does not add up as the traverse is being performed. Azimuth swing
errors can also be reduced by increasing the distance between stations.
1.0 INTRODUCTION TO TRAVERSING
FIGURE 1.1A Traversing FIGURE 1.1B Traversing
Source :https://billboyheritagesurvey.files.wordpress.com/2
010/06/andys-traverse-diagram.png
Source : http://3.bp.blogspot.com/-f3n3he-
1VSc/UXpqD1j74RI/AAAAAAAACuk/KsXLjlhY
b7M/s200/traverse+survey+.jpg
Electronic Device
Measurement
(EDM)
4. 4 | P a g e
1.4 Tools Used
Figure 1.4A Theodolite
Source :http://surveyequipment.com/media/catalog/prod
uct/cache/1/image/903be06a881aa18fc50d3dc96e8b9fba
/p/r/prexiso-to2-theodolite-8234177.jpg?1496765241
Figure 1.4B Total Stations
Source : https://2.imimg.com/data2/DL/YX/MY-
802479/topcon-electronic-total-station-500x500.jpg
THEODOLITE
TOTAL STATIONS
STEEL TAPE
Figure 1.4C Steel Tape
Source :http://surveyequipment.com/media/catalog/prod
uct/cache/1/image/903be06a881aa18fc50d3dc96e8b9fba/
f/i/fisco-pacer-tape_1_2.jpg?1496781783
5. 5 | P a g e
1.5 TYPE OF TRAVERSE
There are two types of traverse surveying, which are:
Open traverse
Closed Traverse
1.5.1 Open Traverse
An open, or free traverse is called a first class traverse which starts at a known points
plotted in any corresponding linear direction, but do not return to starting point or close
upon a point of equal or greater order accuracy. Open traverse is sometimes being used
on route surveys but they should be avoided because an independent check for errors and
mistakes is not available and the only mean of verifying id to repeat all measurements and
computations.
ROUTE SURVEYS
Route surveys is utilized in plotting a strip of land which can then be use route in road/
railway construction.
Figure 1.5.1A Open Traverse
Source :https://upload.wikimedia.org/wikipedia/commons/thumb/4/4a/Open_traverse.png/250px-
Open_traverse.png
Figure 1.5.1B Route Survey
6. 6 | P a g e
1.5.2 Closed Traverse
Closed traverse which is called as second class traverse is a practice of traversing when
the terminal point closes at the starting point. The control points may envelop, or are set
within the boundaries, of the control network. It allows geodetic triangulation for sub-closure
of all known observed points. There are 2 types of closed traverse which are:
Loop Traverse
Connecting Traverse
LOOP TRAVERSE
Loop traverse is one enclosing defined area and have a common points for its beginning to
the end. A closed geometric figure – useful in marking the boundaries of wood/ lakes or
properties.
CONNECTING TRAVERSE
Connecting traverse looks like an open traverse except that it begins and ends at points/
lines of known position/ direction at each of the end of traverse
Figure 1.5.2A Closed Loop Traverse
Source :http://files.carlsonsw.com/mirror/manuals/Carlson_2014/source/CGSurvey/CGTrav/Reduce_Tra
verse/Closed_Beg_and_End_known_Traverse.bmp
Figure 1.5.2A Closed Connecting Traverse
Source : http://www.globalsecurity.org/military/library/policy/army/fm/6-2/fig5-6.gif
7. 7 | P a g e
1.6 COMPONENTS OF TRAVERSE
To plot a traverse, bearing which acts as a direction and length of line is needed
1.6.1 Length of Each Traverse Line
Traditionally, this was don’t by using a steel band and applying a series of
correction to allow for the sagging of the tape, temperature effects and so on
Length of line can be done electronically with the Surveyor using a highly
sophisticated Total Station that can measure both
1.6.2 Bearing
Bearing of a line is its orientation with respect to grid north. May be found for an
initial line by starting at a station with known coordinates and orienting the Total
Station with respect to another point.
The directions due to East and West are perpendicular to North-South meridian
A line may fall in one of four quadrant which are :
May be found for an initial line by starting at a statin with unknown coordinates and
orienting the Total Station with respect to another point with known National Grid
coordinates whereby :
The Surveyor will locate the Total Station accurately over each traverse
station in turn and will measure the horizontal angles.
These measurements are to a high level accuracy and several readings will
be taken to minimise the possibilities of measurement errors.
Angles of bearing are being measured in degrees, minutes and seconds whereby a
bearing cannot be more than 90 degrees.
Figure 1.6.2A Bearing
Source : https://gs-blog-images.grdp.co/blogs/wp-content/uploads/2016/08/27015428/10.png
8. 8 | P a g e
1.6.3 Azimuth
An azimuth is a clockwise angular measurement in a spherical coordinate system, between
the line and a given reference direction or meridian in a spherical coordinate system, The
vector from an observer which is the origin to a point of interest is projected perpendicularly
onto a reference plane. The angle between the projected vector and a reference vector on
the reference plan is called the azimuth.
1.6.4 Latitude and Departure of a Line
Latitude
Projection on the North-South meridian and is equal to the length of the cosine of
its bearing.
Departure
Projection on the East-West meridian and is equal to the length of the line times
the sine of the bearing
Figure 1.6.3A Azimuth
Source :
https://upload.wikimedia.org/wikipedia/commo
ns/thumb/f/f7/Azimuth-
Altitude_schematic.svg/350px-Azimuth-
Altitude_schematic.svg.png
Figure 1.6.3B Explaining Azimuth
Figure 1.6.4A Latitude and Departure
Source :
http://www.cfr.washington.edu/classes.esrm.304/Spri
ng2011/Documents/Hurvitz_Schiess/procedures/imag
es/image0002.gif
9. 9 | P a g e
1.6.5 Error Of Closure
Error of closure is the amount by which a closed traverse fails to satisfy the requirements of
a true mathematical figure, as the length of line joining the true and computed position of
the same point. The ratio of this linear error to the perimeter of the traverse. Nevertheless, it
is expected that data taken from a survey will not close exactly. If the error on closure is
acceptably small, the data are improved by corrections calculated from error. The method
will then be explained in text further. If the closure exceeds acceptable limit, surveys has to
be repeated.
1.6.6 Station Selection
Selecting a station should be precisely done to avoid increasing the work of measuring
traverse which is by positioning the control traverse stations as close as possible to the
features or objects to be located. Nevertheless, establishing too many points increases the
time and cost of survey and establishing too few points may not provide sufficient control
for the project. Selection of positions control traverse stations has to be precisely done due
to the uneven varying terrains which can be an obstacles.
Figure 1.6.4A Latitude and Departure
Source : http://surveying.structural-analyser.com/_internal/images/ErrorOfClosure_622x416.png
Figure 1.6.6A Selection of Station
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(n – 2)(180°)
1.7 TRAVERSE COMPUTATION
Traverse computation is the process of taking field measurement through aserioes
of mathematical calculation to determine final traverse size and configuration. These
calculations include error compensation as well as reformation to determine
quantities not directly measured.
Traverse computation steps are:
1.7.1 BALANCE AND ADJUSTING ANGLES
Before the areas of a place of land can be computed, it is necessary to have
closed traverse.
The interior angle of the closed traverse should be total of
Where n is the number of sides of the traverse
1.7.2 DETERMINING THE BEARINGS AND LINE OF DIRECTIONS
Figure 1.7.1A Selection of Station
Source : http://www.globalsecurity.org/military/library/policy/army/fm/3-34-331/ch5-1.gif
Figure 1.7.2A Selection of Station
Source : http://www.globalsecurity.org/military/library/policy/army/fm/3-34-331/ch5-1.gif
11. 11 | P a g e
1.7.3 DETERMINING THE BEARINGS AND LINE OF DIRECTIONS
Latitude
- Lines with Northerly bearing – (+) LAT
- Lines with Southerly bearing – (-) LAT
- L cos ᵝ
Departure
- Lines with Easterly bearing – (+) DEP
- Lines with Westerly bearing – (-) DEP
- L sin ᵝ
BY USING BEARING
1.7.4 ACCURACY CHECK
Accuracy check or acceptable misclosure
An average ratio of 1: 3000 is acceptable in land surveying
Figure 1.7.3A Latitude and Departure – Azimuth
Source : https://image.slidesharecdn.com/fieldwork2ss-2-141203080515-conversion-
gate01/95/fieldwork-2-7-638.jpg?cb=1417593945
Error in Latitude
Error in Departure
Total Error =
1 : Length of Traverse/
Ec
Ec
12. 12 | P a g e
1.7.4 ADJUSTING TRAVERSE MISCLOSURE
Correction in Latitude
Total Latitude Misclosure
Traverse Perimeter
Correction in Departure
Total Departure Misclosure
Traverse Perimeter
1.7.5 DETERMINE ADJUSTED LINE LENGTHS AND DIRECTIONS AND COMPUTING COORDINATES
N₂ = N₁ + Lat₁₋₂
E₂ = E₁ + Dep₁₋₂
Where,
N₂ and E₂ = the Y and X coordinates of Station 2
N₁ and E₁ = the Y and X coordinates of Station 1
Lat₁₋₂ = the latitude of course 1-2
Dep₁₋₂ = the departure of course 1-2
X Length of Station
X Length of Station
Figure 1.7.4A Adjusting traverse misclosure
Source : http://engineeringtraining.tpub.com/14070/img/14070_131_18.jpg
14. 14 | P a g e
2.1 THEODOLITE
Theodolite is an instrument for measuring both horizontal and vertical angles, as used in
triangulation networks, and geo-location work. It is a tool used in the land surveying and
engineering industry, but theodolites have been adapted for other specialized purposes as
well. Other specialized purposes make Theodolites ideal for shop and factory floor layout of
tools and fixtures. They also work well for layout for the construction of concrete slabs,
swimming pools, golf courses, landscaping, and road design.
The horizontal accuracy of Theodolites depends on "seconds". A 2-second theodolite is
more accurate than a 5 or 9-second theodolite. If you think about the horizontal circle that a
theodolite rotates around, the circle is divided into 360 degrees. Each degree is divided
into 60 minutes, and each minute divided into 60 seconds. Think "Degrees / Minutes /
Seconds". The horizontal angle is the measure of inaccuracy (hence accuracy) that a
theodolite can horizontally measure or locate within. If a theodolites accuracy rating is 2
seconds (written 2") then it’s only going to lose 2 seconds of horizontal measurement in a
given distance. Generally speaking, a 9 second theodolite is for construction sites where
you're working relatively up close, say within 200 feet from the instrument. A 2 second you
would work 2,000 feet away and still work with some level of accuracy.
Most building contractors, whether residential or commercial, can use a 9 second
theodolite without experiencing problems due to accuracy. At this distance, more errors are
in the form of human errors, such as not levelling the instrument properly or taking a quick
reading which lends itself to human error.
2.0 OUTLINE APPARATUS
Figure 2.1A Theodolite
Source :http://surveyequipment.com/media/catalog/product/cache/1/image/903be06
a881aa18fc50d3dc96e8b9fba/p/r/prexiso-to2-theodolite-8234177.jpg?1496765241
15. 15 | P a g e
Like other leveling instruments, a theodolite consists of a telescope mounted on a base.
The telescope has a sight on the top of it that is used to align the target. The instrument has
a focusing knob that is used to make the object clear. The telescope contains an eyepiece
that the user looks through to find the target being sighted. An objective lens is also located
on the telescope, but is on the opposite end as the eyepiece. The objective lens is used to
sight the object, and with the help of the mirrors inside the telescope, allows the object to
be magnified. The theodolite's base is threaded for easy mounting on a tripod.
A theodolite works by combining optical plummets (or plumb bobs), a spirit (bubble level),
and graduated circles to find vertical and horizontal angles in surveying. An optical
plummet ensures the theodolite is placed as close to exactly vertical above the survey
point. The internal spirit level makes sure the device is level to to the horizon. The
graduated circles, one vertical and one horizontal, allow the user to actually survey for
angles
Figure 2.1B Side View of Theodolite
Source : http://www.johnsonlevel.com/Content/files/TheodoliteParts.png
Figure 2.1C Sectional View of Theodolite
Source : http://www.johnsonlevel.com/Content/files/TheodoliteParts.png
16. 16 | P a g e
2.2 ADJUSTABLE LEG TRIPOD ( TRIPOD STAND )
A surveyor's tripod is a device used to support any one of a number of surveying
instruments, such as theodolites, total stations, levels or transits.
Modern tripods are constructed of aluminum, though wood is still used for legs. The feet are
either aluminum tipped with a steel point or steel. The mounting screw is often brass or
brass and plastic. The mounting screw is hollow and has two lateral holes to attach
a plumb bob to center the instrument e.g. over a corner or other mark on the ground.
After the instrument is centered within a few cm over the mark, the plumb bob is removed
and a viewer (using a prism) in the instrument is used to exactly center it.
https://4.imimg.com/data4/WH/YB/MY-1658977/aluminium-tripod-for-auto-level-500x500.png
The tripod is placed in the location where it is needed. The surveyor will press down on the
legs' platforms to securely anchor the legs in soil or to force the feet to a low position on
uneven, pock-marked pavement. Leg lengths are adjusted to bring the tripod head to a
convenient height and make it roughly level and being locked by a lever clamp ( left ) or
screw (right).
Once the tripod is positioned and secure, the instrument is placed on the head. The
mounting screw is pushed up under the instrument to engage the instrument's base and
screwed tight when the instrument is in the correct position. The flat surface of the tripod
head is called the foot plate and is used to support the adjustable feet of the instrument.
Positioning the tripod and instrument precisely over an indicated mark on the ground or
benchmark requires intricate techniques.
Figure 2.2A Adjustable Leg Tripod
Figure 2.2B clamp and screw of leg tripod
17. 17 | P a g e
2.3 LEVELING ROD / LEVELING STAFF
A level staff, also called levelling rod, is a graduated wooden or aluminium rod, used with
a levelling instrument to determine the difference in height between points or heights of
points above a datum surface. It cannot be used without a leveling instrument.
Levelling rods can be one piece, but many are sectional and can be shortened for storage
and transport or lengthened for use. Aluminum rods may be shortened by telescoping
sections inside each other, while wooden rod sections can be attached to each other with
sliding connections or slip joints, or hinged to fold when not in use.
There are many types of rods, with names that identify the form of the graduations and
other characteristics. Markings can be in imperial or metric units. Some rods are graduated
on one side only while others are marked on both sides. If marked on both sides, the
markings can be identical or can have imperial units on one side and metric on the other.
Figure 2.3A leveling staffs
18. 18 | P a g e
Reading the Leveling Staff
The staff starts at zero, on the ground. Every 10 cm is a number, showing (in meters to one
decimal) the height of the bottom of what appears to be a stylized E (even numbers) or 3
(odd numbers), 5 cm high. The stems of the E or 3 and the gaps between them are each
10mm high. These 10mm increments continue up to the next 10 cm mark.
To read the staff, take the number shown below the reticle. Count the number of whole
10mm increments between the whole number and the reticle. Then estimate the number of
mm between the last whole 10mm block and the center of the reticle. The diagram above
shows 4 readings:- 1.950, 2.000, 2.035 and 2.087.
The person holding the staff should endeavor to hold it as straight as possible. The leveler
can easily see if it is tilted to the left or right, and should correct the staff-holder. However, it
cannot easily be seen that the staff is tilted towards or away from the leveler. In order to
combat this possible source of error, the staff should be slowly rocked towards and away
from the leveler. When viewing the staff, the reading will thus vary between a high and low
point. The correct reading is the lowest value.
Digital levels electronically read a bar-coded scale on the staff. These instruments usually
include data recording capability. The automation removes the requirement for the operator
to read a scale and write down the value, and so reduces blunders. It may also compute
and apply refraction and curvature corrections.
Figure 2.3B Reading the leveling staff
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2.4 OPTICAL PLUMMET
In surveying, a device used in place of a plumb bob to centre transits and theodolites over
a given point, preferred for its steadiness in strong winds. The device consists of two
triangular metal plates connected at their corners by levelling thumbscrews, a bubble level,
a locking mechanism and often an optical plummet. The device will be attached to the
tripod and placed over the plummet.
The bubble shown in Figure 2.4B (left) is being adjusted using the foot screw so that the
foot screw can be in the middle of the cross hair as shown in Figure 2.4B (right)
2.5 BULL’S EYES LEVEL ( SPIRIT BUBBLE )
Spirit level is a tool that is being used to indicate how parallel (level) or perpendicular
(plumb) a surface is relative to the earth. A spirit level gets its name from the mineral spirit
solution inside the level.
The vials in a spirit level are yellowish-green colour with additives for UV protection and
maximum performance in temperatures ranging from -20ºF – 130ºF. The best spirit level is
accurate to within plus or minus 0.5 mm/M, or 0.005 inches/inch or 0.029º. The next level of
accuracy displayed is 0.75mm/M or 0.043º.
The vial bodies of a spirit level, also referred as a bubble level can be shaped like a barrel,
like rectangular block or even curved, banana-shaped, to measure slope in fractions per
foot of pitch, and are mostly made from acrylic today versus glass originally.
Sensitivity is an important specification for spirit level as the accuracy depends a lot on the
sensitivity. The sensitivity of level is given as the change of angle or gradient required to
move the bubble by unit distance.
Figure 2.4A Optical Plummet
Figure 2.5 Spirit Bubble
20. 20 | P a g e
2.6 RANGING ROD
A ranging rod is a surveying instrument used for marking the position of stations and for
sightings of those stations as well as for ranging straight lines. Initially these were made of
light, thin and straight bamboo or of well-seasoned wood such as teak, pine or deodar.
They were shod with iron at the bottom and surmounted with a flag about 25 cm square in
size. Nowadays they are made of metallic materials only.
The rods are usually 3 cm in diameter and 2 m or 3 m long, painted alternatively
either red and white or black and white in lengths of 20 cm (i.e. one link length of metric
chain). These colors are used so that the rod can be properly sited in case of long distance
or bad weather. Ranging rods of greater length, i.e., 4 m to 6 m, are called ranging poles
and are used in case of very long survey lines. Ranging poles are usually painted with
alternate red-white and black-white bands. If possible wooden ranging poles are reinforced
at the bottom by metal points.
Another type of ranging rod is known as an offset rod, which has no flag at the top. It is
used for measuring small offsets from the survey line when the work is of an ordinary
nature.
Figure 2.6A Ranging Rod and Offset rod
Source : http://www.civilengineeringx.com/building/bce/rod.jpg
Figure 2.6A Ranging Rod
Source : https://2.imimg.com/data2/YJ/IT/MY-2739368/ranging-rod-250x250.jpg
21. 21 | P a g e
2.7 PLUMB BOB
The plumb bob or plumb line employs the law of gravity to establish what is “plumb” (that
is, what is exactly vertical, or true). You don’t have to be a physics whiz to understand that a
string suspended with a weight at the bottom will be both vertical and perpendicular to any
level plane through which it passes. In a sense, the plumb bob is the vertical equivalent of
the line level or also called as the “water-level”
The plumb consists of a specially designed weight and coarse string made of twisted
cotton or nylon threads. (Masons prefer nylon because it stands up better over time to the
dampness that comes with the trade.) At one end of the string the weight is affixed.
Precisely machined and balanced bobs have pointed tips, and can be made of brass,
steel, or other materials, including plastic.
Surveyors sometimes use plumb bobs for lining up points or transferring
them. Excavation and foundation contractors rely upon the plumb line, and constructing a
chimney the tool can indicate whether a flue is running true vertical or veering off plumb.
Figure 2.7A Plumb Bob
Source : https://cdn2.tmbi.com/TFH/Step-By-Step/display/FH04FEB_LEVTIP_07.JPG
Figure 2.7B Plumb Bob
Source :
https://www.wonkeedonkeetools.co.uk/media/wysiwyg
/11PB-Plumb-Bobs-David/11PB04/11PB-4-
8_TBTW_Plumb-
bob_with_ring_attached_for_string_.jpg
Figure 2.7C Plumb Bob
Source :
https://www.wonkeedonkeetools.co.uk/media/wysiw
yg/11PB-Plumb-Bobs-David/11PB04/11PB-4-
1_TB_Plumb-bob_with_labelled_parts_.jpg
22. 22 | P a g e
To learn the principles of running a close field traverse
To enhance student’s knowledge in traversing
To establish ground control for photographic mapping.
To enable student to identify the error and make adjustment to the data.
To enable student to get hands-on experience in the usage of theodolite.
To be familiar with types and methods of traverse surveying.
3.0 OBJECTIVE
23. 23 | P a g e
Theodolite
Station
Station Sighted Top Reading Bottom Reading Vertical θ Horizontal θ
Height of
Theodolite
First
Reading
A B 218.60 181.00 88°33'20" 0 115 mm
A D 210.60 189.40 87°40'00" 70°34'20"
Second
Reading
A B 219.00 181.00 271°27'00" 0
A D 210.90 189.50 272°20'40" 70°34'00"
First
Reading
B C 211.30 189.00 88°28'20" 0 116.30mm
B A 218.90 181.50 88°51'40" 102°54'40"
Second
Reading
B C 211.00 189.00 271°32'00" 0
B A 218.50 181.50 271°08'00" 102°54'00"
First
Reading
C D 217.70 182.10 88°39'40" 0 131.30mm
C B 211.00 189.00 87°35'40" 74°32'10"
Second
Reading
C D 217.50 182.10 271°20'20" 0
C B 211.00 189.00 272°24'20" 74°32'30"
First
Reading
D A 210.40 189.40 87°47'40" 0 119.10mm
D C 217.60 182.30 88°57'20" 111°56'00"
Second
Reading
D A 210.50 189.40 272°12'40" 0
D C 217.50 182.00 271°02'40" 111°56'20"
4.0 FIELD DATA
24. 24 | P a g e
Theodolite Station Station Sighted Top Reading Bottom Reading Vertical θ Horizontal θ
A B 218.80 181.00 88°33'10"
A D 210.75 189.45 87°39'40" 70°34'10"
B C 211.15 189.00 88°28'10"
B A 218.70 181.50 88°51'50" 102°54'20"
C D 217.60 182.10 88°39'40"
C B 211.00 189.00 87°35'40' 74°32'20"
D A 210.45 189.40 88°28'10"
D C 217.55 182.20 88°51'50" 111°56'10"
4.1 FIELD AVERAGE DATA
25. 25 | P a g e
STATION
FIELD ANGLES
DEGREE (°) MINUTE (‘) SECOND (“)
A 70 34 10
B 102 54 20
C 74 32 20
D 111 56 10
SUM 357 176 60
359 57 00
4.3 FIELD DATA
A
D
C
B
70° 34’ 10”
111° 56’ 10”
102° 54’ 20”
74° 32’ 20”
26. 26 | P a g e
4.1
Interior Angle = (n-2) X 180°
= (4-2) X 180°
= 360°
Total Angular Error = 360° - 359° 57’ 00”
= 00° 03’ 00”
Error Per Angle = 00° 03’ 00” ÷ 4
= 00° 00’ 45” / 45” per angle
STATION FIELD ANGLE CORRECTION ADJUSTED ANGLE
A 70° 34’ 10” + 00° 00’ 45” 70° 34’ 55”
B 102° 54’ 20” + 00° 00’ 45” 102° 55’ 5”
C 74° 32’ 20” + 00° 00’ 45” 74° 33’ 5”
D 111° 56’ 10” + 00° 00’ 45” 111° 56’ 55”
TOTAL 359° 57’ 00” + 00° 03’ 00” 360° 00’ 00”
4.4 ANGULAR ERROR & ANGLE ADJUSTMENT
27. 27 | P a g e
STATION
FIELD ANGLES
DEGREE (°) MINUTE (‘) SECOND (“)
A 70 34 55
B 102 55 05
C 74 33 05
D 111 56 55
SUM 357 178 120
360 00 00
4.5 ADJUSTED DATA
A
D
B
70° 34’ 55”
111° 56’ 55”
102° 55’ 5”
74° 33’ 5”
C
28. 28 | P a g e
STATION BEARING
A
B
C
D
A
A
D
B
C
70° 34’ 55”
102° 55’ 5”
111° 56’ 55”
74° 33’ 5”
180° - 102° 55’ 5” - 10°
= 67° 04’ 55”
74° 33’ 5” - 67° 04’ 55”
= 7° 28’ 10”
180° - 111° 56’ 55” - 7° 28’ 10”
= 60° 34’ 55”
S 60° 34’ 55” E
N 10° E
N 67° 04’ 55” W
S 7° 28’ 10” W
S 60° 34’ 55” E
4.6 COURSE BEARING & AZIMUTH
29. 29 | P a g e
D = K x s x cos² (θ) + C x cos (θ)
Where,
D = horizontal distance between survey point and instrument
S = Difference between top stadia and bottom stadia
Θ = vertical angle of telescope from the horizontal line when capturing
the stadia reading
K = multiplying constant given by the manufacturer of the theodolite,
(normally = 100)
C = addictive factor given by the manufacturer of the theodolite,
(normally = 0)
DISTANCE BETWEEN A AND B
B – A = 100 x (2.187 – 1.815) x cos² (90° - 88° 51’ 50”)
= 100 x (0.372) x cos² (1° 8’ 10”)
= 37.185
A – B = 100 x (2.188 – 1.810) x cos² (90° - 88° 33’ 10”)
= 100 x (0.378) x cos² (1° 26’ 50”)
= 37.776
Average Distance = (37.185 + 37.776) ÷ 2
= 37.481
DISTANCE BETWEEN B AND C
C – B = 100 x (2.110 – 1.890) x cos² (90° - 87° 35’ 40”)
= 100 x (0.22) x cos² (2° 24’ 20”)
= 21.961
B – C = 100 x (2.112 – 1.890) x cos² (90° - 88° 28’ 10”)
= 100 x (0.222) x cos² (1° 31’ 50”)
= 22.184
Average Distance = (21.961+22.184) ÷ 2
= 22.073
4.7 STADIA METHOD (DISTANCE/LENGTH)
30. 30 | P a g e
DISTANCE BETWEEN C AND D
D – C = 100 x (2.176 – 1.822) x cos² (90° - 88° 57’ 20”)
= 100 x (0.354) x cos² (1° 2’ 40”)
= 35.388
C – D = 100 x (2.176 – 1.821) x cos² (90° - 88° 39’ 40”)
= 100 x (0.355) x cos² (1° 20’ 20”)
= 35.481
Average Distance = (35.388 + 35.481) ÷ 2
= 35.435
DISTANCE BETWEEN D AND A
A – D = 100 x (2.108 - 1.895) x cos² (90° - 87° 39’ 40”)
= 100 x 0.213 x cos² (2° 20’ 20”)
= 21.265
D – A = 100 x (2.105 – 1.894) x cos² (90° - 87° 47’ 30”)
= 100 x 0.211 x cos² (2° 12’ 30”)
= 21.069
Average Distance = (21.265 + 21.069) ÷ 2
= 21.167
31. 31 | P a g e
4.5
cos ᵝ sin ᵝ L cos ᵝ L sin ᵝ
Station Bearing, ᵝ Length, L Cosine Sine Latitude Departure
A
B
C
D
A
TOTAL ∑= 116.156 ∑= -0.023 ∑=+0.010
ACCURACY CHECK
FORMULA = 1: (∑ Length/ Ec)
= 1: (116.156 / 0.025)
= 1: 4646.24
Therefore, traversing is ACCEPTABLE
N 10° E 37.481
N 67° 04’ 55” W
S 7° 28’ 10” W
S 60° 34’ 55” E 21.167
35.435
22.073
+ 18.438
0.9211 + 8.5960.3894
+ 6.5090.1736 + 36.9120.9848
- 10.3970.4912
- 4.6060.1299 - 35.1340.9915
- 20.331
0.8711
ERROR IN LATITUDE
∑ ∆ L cos ᵝ = - 0.023
ERROR IN DEPARTURE
∑ ∆ L sin ᵝ = + 0.010
A
A’
TOTAL ERROR
√-0.023² + 0.010² = 0.025
EC
4.8 LATITUDE & DEPARTURE
32. 32 | P a g e
4.6 ADJUSTMENT OF LATITUDE AND DEPARTURE
Station
UNADJUSTED CORRECTIONS ADJUSTED
Latitude Departure Latitude Departure Latitude Departure
A
B
C
D
A
TOTAL - 0.023 + 0.010 + 0.023 - 0.010 0 0
CHECK CHECK
The Compass Rule
Correction = - [∑∆y] / P x L or – [∑∆x] / P x L
Where,
∑∆y and ∑∆x = Error in latitude or in departure
P = Total length or perimeter of the traverse
L = The length of a particular course
4.7 COORDINATES
Station N Coordinate *Latitude E Coordinate* Departure
A 100.000 118.436 Start / return here for
lat. check
+ 36.920 + 6.506
B 136.920 124.942
+ 8.600 -20.333
C 145.520 104.609
- 35.127 -4.609
D 110.393 100.000 Start / return here
for dep. check
- 10.393 + 18.436
A 100.000 118.436
+ 36.912
+ 8.596
- 35.134
- 10.397
+ 6.509
- 20.331
- 4.606
+ 18.438
- 0.002
+36.920
+ 0.004
+ 0.008
+ 0.007
+ 0.004
- 0.003
- 0.003
- 0.002
+ 6.506
- 35.127
- 10.393
+ 8.600
- 4.609
+ 18.436
- 20.333
33. 33 | P a g e
50
100
150
200
50 100 150
north,N
East, E
THE ADJUSTED LOOP TRAVERSE PLOTTED BY COORDINATES
A
N 100.000
E 118.436
N 136.920
E 124.942
N 110.393
E 100.000
N 145.520
E 104.609
B
C
D
34. 34 | P a g e
4.8 AREA OF TRAVERSE
AREA = ½ x {[(EA x NB) + (EB x NC) + (EC x ND) + (ED x NA)] – [(NA x EB) + (NB
x EC) + (NC x ED) + (ND x EA)] }
= ½ x {[(118.436 x 136.920) + (124.942 x 145.520) + (104.609 x 110.393) +
(100.000 x 100.000)] – [(100.000 x 124.942) + (136.920 x 104.609) +
(145.520 x 100.000) + (110.393 x 118.436)]}
= ½ x {[55945.918] – [54443.769]}
= ½ x (1502.148)
= 751.074 m²
35. 35 | P a g e
FROM LEFT TO RIGHT : YAP CHOE HOONG, TANG LAM YU, TEE WAN NEE,
WONG SHER SHENG, TEO CHIANG LOONG
5.0 GROUP PHOTO
36. 36 | P a g e
In this second fieldwork, a closed loop traverse survey is being carried out. The
survey was done at car park. A closed loop traverse starts and ends at the same point. Due
to this special characteristics, we are able to form a closed geometric figure. So we were
assigned a group which consists of 5 peoples. We work as a team where one of us is
recording down the data, two of us is taking the reading for the survey and another two is
holding the leveling staff.
Theodolite is used to measure the angle of 4 points(A,B,C,D). We placed the
theodolite at point A and the horizontal angle of point A is taken by reading the theodolite
through point D to B. in order to maintain the accuracy of the reading, the readings must
read from left to right. Horizontal and vertical angle are also taken down. The steps are
repeated for the remaining points. Furthermore, top, middle and bottom stadia readings
have also been recorded for calculation purposes.
For this second fieldwork, we need to take second attempt since we failed to get an
accurate result in the first attempt. This is because we may have not get use to the
equipment. For the second attempt, we enquiry our lecturer about the correct way to use
the theodolite and we have successfully to get an accurate result. An average accuracy is
1:3000.
After the fieldwork have completed, we have learnt that group work and team
cooperation are vital in this fieldwork. The survey could not be done smoothly if one of the
group member is absence. This fieldwork let us learn some hands-on knowledge where we
could not get it from the lecture. Lastly, we appreciate the help of our lecturer in this
fieldwork. We hope that we can get more opportunity in the future to get more hands-on
knowledge.
6.0 CONCLUSION
37. 37 | P a g e
1. http://www.ce.memphis.edu/1112/notes/project_3/traverse/Surveying_traverse.pdf
2. https://web.statler.wvu.edu/~ddean/CE305/Disk1/6%20TraversingSurveying/travcal_1.pdf
3. https://sites.google.com/site/civilengineeringwebsite/our-pastors
4. http://www.raeng.org.uk/publications/other/8-traverse
5. http://www.hbp.usm.my/hilmy/traverse.pdf
6. http://cms.cerritos.edu/uploads/dmussaw/open%20and%20closed%20traverse.pdf
7. https://what-is-this.net/en/define/azimuth
7.0 REFERENCES