SCHOOL OF ARCHITECTURE, BUILDING AND DESIGN

BACHELOR OF QUANTITY SURVEYING (HONOURS)

MARCH 2016 INTAKE

SITE SURVEYING [QSB 60103]

FIELDWORK 2 REPORT

TRAVERSE

GROUP MEMBERS:

NAME STUDENT ID

PANG KAI YUN 0319802

SAM WEI YIN 0320364

TRACE GEW YEE 0320269

YEO KAI WEN 0319844

LECTURER: MR. CHAI VOON CHIET

CONTENT

No. Content Page Number

1. Objectives 2

2. Introduction 3

3. Raw Data 7

4. Adjusted Data 12

5. Discussion 20

6. References 22

1

OBJECTIVES

To enhance our knowledge based on the process of Theodolite.

To enable to have a basic knowledge on how to set up the instruments such as

Theodolite rather than learning from the books.

To apply the theories that had been taught in class.

To have an experience using Theodolite while setting up, collaborating, levelling and

recording the data that have been collected.

To learn how to analyze the data.

To identify the reduced level of each station and spot of relative height.

To determine the difference in height of the points.

To experience the life being as a quantity surveyor and expose the actual working

environment such as working under the hot weather in site.

To determine the error of the misclosure in order whether is it acceptable or not on

the levelling calculations.

To know the precautions while using the Theodolite.

To boost the ability of teamwork while doing on fieldwork.

2

INTRODUCTION TO TRAVERSING

What is traversing?

Traverse is a common method of surveying and a method of establishing horizontal

controls. In other way, it is also a type of survey in which a number of connected survey lines

form the framework and the directions and lengths of the survey lines are measured with the

help of an angle measuring instrument and a tape or chain respectively. Besides, it also

have the series of connected lines forming or not forming a loop which are called closed

traverse (when the loop is formed) and called open traverse (when loop is not formed).

Types of Traverse

1. Open Traverse

An open traverse is one which does not close on the point of the beginning. It is a series

of measured straight lines and angles that do not geometrically close. Computational check

is not possible to detect error or blunder in distance and directions. To minimize error,

repeated observations for measurements need to be taken.

3

2. Closed Traverse

A closed traverse is one enclosing a defined area and having a common point for its

beginning to end.

There are two types of Closed Traverse which are:-

Loop Traverse Loop traverse starts and ends at the same point, forming a polygon.

Loop traverse is suitable for many engineering surveys.

Connecting Traverse It is quite similar to Open Traverse, however the only difference is it begins

and ends at point of known position at each end of traverse.

4

Apparatus Used For Levelling

Theodolite

A Theodolite is an instrument for measuring both horizontal and vertical angles, and mostly

used in traversing. It is a tool which used in the land surveying and engineering industry, but

theodolites have been adapted for other specialized purposes as well. It consists of a

telescope mounted that able to swivel both horizontal and vertical. It is accomplished by the

levelling with the help of spirit level and crosshairs that allow to show the accurate alignment

with the object in the telescope.

Tripod

This instrument is easy to set up due to each leg can be adjusted to the required height. The

function of this instrument is to ensure a stable instrument setup for reliable measurements

to get the accurate data and readings.

5

Plumb Bob

A plumb bob used the law of gravity. That the plumb bob or a plummet is a weight, usually with a pointed tip on the bottom, which is suspended from a string and used as a vertical and perpendicular reference line or plumb-line to any level plane through which passes.

Bar-Coded Level Rod

It is a aluminium rod that have a rectangular cross section. An instrument that used to

determine the relative heights of the different points. The lower end of the rod is shod with

metal to protect from wear. The instrument is sectional and it can be shortened for storage

and lengthened for use.

6

RAW DATA

Station Station Sighted

FacingStadia Reading

Horizontal Angle

Vertical AngleTop Middle Bottom

A

BLeft 138.5

132.5

126.596°59′00′′

90°18′20′′

Right 138.5 126.5 270°11′40′′

DLeft 138.5 126.5

97°03‘40‘’90°24′20′′

Right 138.8 126.6 269°43′40′′

B

ALeft 142.5

136.5

130.589°04’00’’

90°00′40′′

Right 142.4 130.0 269°58′20′′

CLeft 142.5 130.5

89°10’00’’89°38′40′′

Right 142.5 130.5 270°21′20′′

C

BLeft 140.2

134.0

128.391°39’20’’

89°57′00′′

Right 140.5 128.4 270°02′40′′

DLeft 141.3 127.8

91°35’20’’90°01′20′′

Right 141.2 127.9 269°58′20′′

D

CLeft 134.6

128.0

121.383°05’40’’

89°56′40′′

Right 134.5 121.4 270°01′40′′

ALeft 134.1 121.9

83°08’20’’89°36′00′′

Right 134.0 121.8 270°23′20′′

Angles Calculation

Angle A = (96° 59′ 00′′ + 97° 03’ 40”) / 2 = 97° 01’ 20”

Angle B = (89° 04’ 00” + 89° 10’ 00”) / 2 = 89° 07’ 00”

Angel C = (91° 39’ 20” + 91° 35’ 20”) / 2 = 91° 37’ 20”

Angel D = (83° 05’ 40” + 83° 08’ 20”) / 2 = 83° 07’ 00”

7

Distance Calculation

The horizontal distances between the survey points and the theodolite can be calculated

using the equations as follows:

D = K × s × cos2 (θ) + C × cos2 (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 readings

K = multiplying constant given by the manufacturer of the theodolite, (normally = 100)

C = additive factor given by the manufacturer of the theodolite, (normally = 0)

Distance A to B

Distance A to B (FL) = 100 × (1.385-1.265) × cos2 (1°) + 0 × cos2 (1°) = 12.00m

Distance A to B (FR) = 100 × (1.385-1.265) × cos2 (1°) + 0 × cos2 (1°) = 12.00m

Average reading = (12.00m + 12.00m) / 2 = 12.00m

Distance B to A

Distance B to A (FL) = 100 × (1.425-1.305) × cos2 (1°) + 0 × cos2 (1°) = 12.00 m

Distance B to A (FR) = 100 × (1.424-1.300) × cos2 (1°) + 0 × cos2 (1°) = 12.40 m

Average reading = (12.00 m + 12.40 m) / 2 = 12.20 m

Average reading AB = (12.00 m + 12.20 m) /2 =12.10 m

8

Distance B to C

Distance B to C (FL) = 100 × (1.425-1.305) × cos2 (1°) + 0 × cos2 (1°) = 12.00 m

Distance B to C (FR) = 100 × (1.425-1.305) × cos2 (1°) + 0 × cos2 (1°) = 12.00 m

Average reading = (12.00 m + 12.00 m) / 2 = 12.00 m

Distance C to B

Distance C to B (FL) = 100 × (1.402-1.283) × cos2 (1°) + 0 × cos2 (1°) = 11.90 m

Distance C to B (FR) = 100 × (1.405-1.284) × cos2 (1°) + 0 × cos2 (1°) = 12.10 m

Average reading = (11.90 m + 12.10 m) / 2 = 12.00 m

Average reading BC = (12.00 m + 12.00 m) /2 =12.00 m

Distance C to D

Distance C to D (FL) = 100 × (1.413-1.278) × cos2 (1°) + 0 × cos2 (1°) = 13.50 m

Distance C to D (FR) = 100 × (1.412-1.279) × cos2 (1°) + 0 × cos2 (1°) = 13.30 m

Average reading = (13.50 m + 13.30 m) / 2 = 13.40 m

Distance D to C

Distance D to C (FL) = 100 × (1.346-1.213) × cos2 (1°) + 0 × cos2 (1°) = 13.30 m

Distance D to C (FR) = 100 × (1.345-1.214) × cos2 (1°) + 0 × cos2 (1°) = 13.10 m

Average reading = (13.30 m + 13.10 m) / 2 = 13.20 m

Average reading CD = (13.40 m + 13.20 m) /2 =13.30 m

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Distance D to A

Distance D to A (FL) = 100 × (1.341-1.219) × cos2 (1°) + 0 × cos2 (1°) = 12.20 m

Distance D to A (FR) = 100 × (1.340-1.218) × cos2 (1°) + 0 × cos2 (1°) = 12.20 m

Average reading = (12.20 m + 12.20 m) / 2 = 12.20 m

Distance A to D

Distance A to D (FL) = 100 × (1.385-1.265) × cos2 (1°) + 0 × cos2 (1°) = 12.00 m

Distance A to D (FR) = 100 × (1.388-1.266) × cos2 (1°) + 0 × cos2 (1°) = 12.20 m

Average reading = (12.00 m + 12.20 m) / 2 = 12.10 m

Average reading DA = (12.20 m + 12.10 m) /2 =12.15 m

10

Station Field Angles Distance (m)

A 97° 01’ 20” 12.10

B 89° 07’ 00” 12.00

C 91° 37’ 20” 13.30

D 83° 07’ 00” 12.15

Sum 360° 59’ 40” 49.55

11

ADJUSTED DATA

1. Compute the Angular Error And Adjust The Angles

The sum of the interior angles in any loop traverse must equal (n-2) x 180° for geometric

consistency.

Sum of the interior = (n-2) x 180°

= (4-2) x 180°

= 360°

Total angular error = 360° 00’ 00” - 360° 52’ 40”

= - 00° 52’ 40”

Error per angle = - 0° 52’ 40” / 4

= - 0° 13’ 10” per angle

Station Field Angles Correction Adjusted Angles

A 97°01’ 20” - 0° 13’ 10” 96° 48’ 10”

B 89° 07’ 00” - 0° 13’ 10” 88° 53’ 50”

C 91° 37’ 20” - 0° 13’ 10” 91°24’ 10”

D 83°07’ 00” - 0° 13’ 10” 82° 53’ 50”

Sum 360° 52’ 40” 360° 00’ 00”

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2. Compute Course Bearings Or Azimuths

Bearings Azimuths

A - B

180° 00’ 10” - 96° 48’ 10” 83° 11’ 50”

S 83° 11’ 50” E

96° 48’ 10”

B - C

N 5° 42’ 00” E

96° 48’ 10”+ 88° 53’ 50” 185° 42’ 00”- 180° 00’ 00” 5° 42’ 00”

C - D 180° 00’ 00”- 97° 06’ 10” 82° 53’ 50”

N 82° 53’ 50” W

5° 42’ 00”+ 91° 24’ 10” 97° 06’ 10”+ 180° 00’ 00” 277° 06’ 10”

D - A S 0° 0’ 0” E 277° 06’ 10”+ 82° 53’ 50” 360° 00’ 00”- 180° 00’ 00” 180° 00’ 00”

13

3. Compute Course for Latitudes and Departures

Station Bearing, β Length, LCos β Sin β L cos β L sin β

Cosine Sine Latitude Departure

A

S 83° 11’ 50” E 12.10 -0.1185 +0.9930 -1.4339 +12.0153

B

N 5° 42’ 00” E 12.00 0.9951 +0.0993 +11.9412 +1.1916

C

N 82° 53’ 50” W 13.30 0.1236 -0.9923 +1.6439 -13.1976

D

S 0°00’00” E 12.15 -1.0000 +0.0000 -12.1500 +0.0000

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A

Perimeter(P) = 49.55 m Sum of latitudes = ∑∆y = 0.0012 m

Sum of departures = ∑∆x = 0.0093 m

4. Determine the Error of Closure and Accuracy

Accuracy = 1: (P/EC)

For average land surveying, an accuracy of about 1: 3000 is typical.

EC = [ (sum of latitude)2 + (sum of departure)2 ]1/2

= [ (0.0012)2 + (0.00093)2 ]1/2

= 0.00938 m

P = 49.55 m

15

Accuracy = 1: (49.55/0.00938)

= 1: 5282.52

Therefore, the traversing is acceptable.

5. Adjust Course Latitudes And Departures

Compass Rule:

Correction = – [ΣΔy] / P x L or – [ΣΔx] / P x L

Where,

ΣΔy and ΣΔx = the error in latitude and departure

P = total length of perimeter of the traverse

L = length of a particular course

StationUnadjusted Corrections Adjusted

Latitude Departure Latitude Departure Latitude Departure

A

-1.4339 +12.0153 - 0.00029 - 0.00227 -1.4342 12.0130

B

+11.9412 +1.1916 - 0.00029 - 0.00225 11.9409 1.1894

C

+1.6439 -13.1976 - 0.00032 - 0.00250 1.6436 -13.2001

D

16

-12.1500 +0.0000 - 0.00029 - 0.00228 -12.1503 - 0.0023

A

0.0012 0.0093 -0.0012 -0.0093 0.0000 0.0000

Check Check

Latitude correction

The correction to the latitude of course AB is - (0.0012/49.55) x 12.10 = - 0.00029

The correction to the latitude of course BC is - (0.0012/49.55) x 12.00 = - 0.00029

The correction to the latitude of course CD is - (0.0012/49.55) x 13.30 = - 0.00032

The correction to the latitude of course DA is - (0.0012/49.55) x 12.15 = - 0.00029

Departure correction

The correction to the departure of course AB is - (0.0093/49.55) x 12.10 = - 0.00227

The correction to the departure of course BC is - (0.0093/49.55) x 12.00 = - 0.00225

The correction to the departure of course CD is - (0.0093/49.55) x 13.30 = - 0.00250

The correction to the departure of course DA is - (0.0093/49.55) x 12.15 = - 0.00228

17

6. Compute Station Coordinates

N₂ = N₁ + Latitude₁₋₂

E₂ = E₁ + Departure₁₋₂

Where,

N₂ and E₂ = Y and X coordinates of station 2

N₁ and E₁ = Y and X coordinates of station 1

Latitude₁₋₂ = Latitude of course 1-2

Departure₁₋₂ = Departure of course 1-2

Station N Coordinate* Latitude E Coordinates* Departure

A 1000.000 1000.000

- 1.4342 + 12.0130

B 998.5658 1012.013

+ 11.9409 + 1.1894

C 1010.5067 1013.2024

+ 1.6436 - 13.2001

D 1012.1503 1000.0023

18

- 12.1503 - 0.0023

A 1000.000 1000.000

The adjusted loop traverse plotted by coordinates.

998 1000 1002 1004 1006 1008 1010 1012 1014990

995

1000

1005

1010

1015

N 1000.0000E 1000.0000 N 998.5658

E 1012.0130

N 1010.5067E 1013.2024

N 1012.1503E 1000.0023

19

Y axis (north)

X axis (east)

D

B

A

C

DISC USSION

In this fieldwork, we need to construct a closed loop traverse using a theodolite the

staff parking at Taylor’s University Lakeside Campus. We are required to measure the

horizontal and vertical angles of any four points which are labelled as A, B, C and D. We had

used about three hours to complete all the scope works.

First of all, we need to place the theodolite at station A and adjust the theodolite until

it is in horizontal level. Moreover, the other stations (A, B, C, D) must be stated on the site to

form a loop traverse by using the white liquid ink. We had moved to the base for four times

to get our field data.

During measuring the angle, the horizontal and vertical angles will be shown on the

digital readout panel. The process of the fieldwork is smoothly. After we get the readings, we

are required to do the error distributions in order to find out more exact angle.

Our total angle for the loop traverse is 360° 52’ 40” and the total angle error is about

- 0° 52’ 40”. Therefore, it has - 0° 13’ 10” error per angle. The accuracy is important to be

calculated to ensure that the mis-closure of the angle is acceptable. The typical accuracy is

1:3000. The accuracy we calculated is 1: 5282.52. Thus, our traversing is acceptable.

20

One of the difficulties we had faced during the fieldwork was we have to ensure that

the spirit bubble have to be exactly at the centre point. At the first time we set up the

theodolite, it took us extra time to let the instrument to be in stabilizes which we have to

make sure that the spirit level is always in the middle in every position. As we had tried more

often, we did more efficiently while making the theodolite to be in a stable state quickly.

In conclusion, this fieldwork was interesting. It was effective for us to broaden our

knowledge on the experiment of the theodolite and adjust the data error in order for us to

find out more exact angel. This is a very great experience and it will definitely help us in our

future.

21

REFERENCES

Civil Engineering. (n.d.). Retrieved June 3, 2016, from

http://surfcivil.blogspot.my/2010/05/traverse-surveying.html

Horizontal control surveys. (n.d.). Retrieved June 4, 2016, from http://surveying.structural-

analyser.com/chapter07/

Introduction to Traversing - Open and closed Traverses. (n.d.). Retrieved June 4, 2016, from

http://www.builtsense.net/topic/239-introduction-to-traversing-open-and-closed-traverses/

Military. (n.d.). Retrieved July 11, 2016, from

http://www.globalsecurity.org/military/library/policy/army/fm/3-34-331/ch6.htm

Surveying Equipment. (n.d.). Retrieved July 11, 2016, from

http://www.engineersupply.com/surveying-equipment.aspx

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