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BUILD ING STRUCTURE TREVOR N JC HOREAU 0308914 / TEH KAH KEN 0314502 / LEE MAY WEN, ANDREA 0314320
CHEN ROU ANN 1001G76463 / WONG KWOK KENN 0300146 / NUR ADILA ZAAS 0310417
I N T R O D U C T I O N
P R E C E D E N T S T U D Y
M A T E R I A L A N D T R U S S A N A LY S I S
M O D E L T E S T I N G
C O N C L U S I O N
A P P E N D I X
R E F E R E N C E S
TABLE OF CONTENT
1 .0 I N T R O D U C T I O N“Introduction of our understanding and briefs”
1.1 OBJECTIVE The aim of this project is to develop a deeper understanding towards
the tensile and compressive strength of construction materials. Students are
required to design a perfect truss bridge with a high level of aesthetic value
and minimal construction materials. The bridge has to be of a 750mm clear
span, not exceeding the maximum weight of 200g. This report is a compilation
of our undertanding and analysis based on precedent studies conducted, con-
struction materials and the deisgn of our truss bridge.
1.2 INTRODUCTION OF TENSION Tension describes the pulling force exerted by each end of any one-
dimensional continuous object, be it a string, rope, cable or wire. The tensile
force is focused along the length of an object and pulls uniformly on opposite
ends of it.
1.3 INTRODUCTION OF COMPRESSION Compressive force (or “compression strength”) refers to the capacity of
a material in resistingpushing forces that are focussed axially. Compressive
force can also be defined as the capacity of a structure to withstand loads
tending to reduce its size.
COMPRESSION TENSION
Image 1
Analysis of
compression (LEFT)
and tension (RIGHT)
IMAGE 1
2.0 P R E C E D E N T S T U D Y“Knowledge and understanding to a id us in designing our fet tuccin i br idge”
Officially opened in 1890, the Forth Road Bridge occupies a beautiful
location in the Firth of Forth on the East coast of Scotland, connecting Fife
and the North of Scotland with capital city Edinburgh and the South. The
bridge is composed of two railway lines cross the Forth Bridge, supported
47.8 meters above high water, linking much of Northern Scotland with
Edinburgh and England to the South. The lines of track sit on a ‘bridge within
a bridge,’ an internal viaduct supported within the enormous cantilever towers
and arms which is often overlooked.Construction techniques as well as design
improvements can be administered due to ongoing advances in design and
construction, the development of materials and reduction of cost in what is
considered a necessity in a modern day bridge.
2 . 1 F O R T H R O A D B R I D G EImage 2Forth Road Bridge
on the east coast of
Scotland
IMAGE 2
The bridge spans up to a total of 2460 meters. It is composed of two
approach viaducts, six cantilever arms supported by three towers, with two
central connecting spans. Abutments (supports the lateral pressure of an arch
or span) are found at the end of each of the two outer-most cantilevers. Two
railway lines sit on an internal viaduct supported within the cantilevered
towers; these carried 47.8 meters above high water.
2 . 2 E L E M E N T S O F T H E B R I D G E
Four of the six cantilever arms are fixed. These are held strongly in
position by the two granite abutments at the ends of each approach viaduct.
Two ‘suspended spans’, over one hundred and five meters long link the two
outer cantilever towers with the central one. In a nutshell, the superstructure
for this bridge functions as a standard truss – with specific members carrying
out either tension or compressive forces.
The centre of the bridge consists of three main piers, with two cantilever
arms built out from each pier. Two viaducts consisting of a pair of lattice
girders each spanning over fifty-one meters lead up to the centre, which is
ultimately supported over forty meters above high-water level on masonry
piers.
Image 3Two men represent
main cantilever
tower
IN COMPARISON
The two men sat on chairs with outstretched arms represent the main
cantilever towers, in between them is a central span connecting the two.
Anchorage for the cantilevers is provided by the bricks at either side. As load
is applied to the central span (in this case by a third man) the outside men’s
arms come into tension, and the sticks they’re holding and the men’s bodies
experience compressive forces. In reality the bridge has three cantilever
towers, but the principle can be applied equally to this third tower. All
compression members (struts) in this bridge are tubular sections made up of
many small steel plates riveted together, while tension is carried in lattice truss
members. Wind bracing is provided by further lattice trusses spanning
between the main superstructure members.
Image 4Elevation drawing of
Forth Road Bridge
The Francis Scott Bridge, also known as Outer Harbour Bridge or Key
Bridge is a continuous truss bridge spanning over the Patapsco River in
Baltimore, Maryland, The United States of America. This is the longest bridge
(17540 metres) in Baltimore and the third longest span (366 metres) of any
continuous truss in the world. Upon completion, the bridge was officially
opened in March 1977 and estimated to carry 11.5 m`illion vehicles annually.
The technique used in the construction of this bridge can be identified as the
Baltimore truss.
2 . 3 F R A N C I S S C O T T B R I D G E
The Baltimore truss is a subclass of the Pratt truss. It is designed to
prevent buckling in the compression members and also control deflection by
having additional bracing in the lower section of the truss. Due to the rigid and
strong design of this truss, it is mainly used for train bridges.
Image 5Axono Angle of
Franciss Scott
Bridge
The construction of this bridge is complicated in which the order of this
bridge is meticulously calculated. It is achieved by having consistent spacing
of the trusses in the middle section of the bridge together with equal spacing
of the suspended cables in the arch section.
Due to the long span of the arch section of the bridge, a suspended,
continuous truss design is used for this span. The suspended cables linking
between the truss and the deck will prevent the deck from any construction
failures due to tensile and compressive forces when there is presence of load
acting on this section. The trusses on top of the deck are in the form of an
arch because of its stronger structural property than the beam and column
form. In addition, the arch adds for aesthetic value to the design. Apart from
that, the arches will transfer loads back into the bearings on the piers then
into the foundation. Steel sections incorporated between front truss and the
back trusses are to provide stability and torsion resistant to the structure.
Image 6Front Photo of Scott
Bridge (Top)
Image 7 Elevation of Pratt
Truss (Left Bottom)
Elevation of
Baltimore Truss
(Right Bottom)
The bridge’s superstructure involved few construction phases. The first
phase involved building all the span of the bridge across the top of the piers
built in the substructure. A total of eleven piers are constructed in reinforced
concrete prior to provide support to the bridge in which the decks are placed.
Later on, they are further supported and strengthen by the continuous truss.
Image 8Cables linking the
truss and deck
together.
The main steel trusses are prefabricated in four major parts, which
the arch truss would be constructed in two parts, and the regular trusses on
the either side of the arch truss. These separated components made up of
I-beams are then transported to the site by heavy lift floating whereby they are
connected together through welding and girder plates with the aid of crags
on ships to hoist the parts 56.4 metres above the decks (highest point of the
span to the deck under) of the bridge.
Image 9Construction of the
truss in multiple
parts.
3.0 M A T E R I A L A N A LY S I S“Before exper iment started, analys ing mater ia ls are the main concern”
3.1 TYPE OF FETTUCCINE ANALYSIS As stated in the brief, fettuccine is the only material used for the model.
With this, the tensile and compressive strength of different brands of fettuc-
cine were studied and tested. The most suitable one to be used for our model
was determine.
Methods: -i. Strips of fettuccine were laid on a flat surface
ii. Load was placed to test the rate of buckling
iii. Time taken until failure was measured in order to determine the strength
& flexibility of the fettuccine
iv. Steps were repeated with a different brand
Results: -i. San Remo
(chosen fettuccine)
ii. Agnesi
iii. Barilla
- carried most weight- medium flexibility- medium rough surface
-carried medium weight
-flexible
-lightweight and thin fetuccini
- carried less weight
-very flexible
-lightest and thinnest fetuccini
Image 10San Remo
Fettuccine (left)
Image 11Agnesi Fettuccine
(middle)
Image 12Barilla
(right)
3.2 ADHESIVE MATERIAL ANALYSIS Different kinds of glue were tested to determine which was more
efficient in terms of holding the fettucine together. The results obtained from
our analysis is stated below: -
RANKING ADHESIVE MATERIALS REASON1 3 Seconds Glue i.Highest efficiency
ii. Dries the fastest
iii.Will flow into smallest
corners and joints
2 Elephant Glue i. Moderate Efficiency
ii. Time consumingin terms
of workmanship
iii. Longer solidify time
3 Hot Glue Gun i. Low Efficiency
ii. Long solidify time
iv. Bulky Finishing
v. Drastic increase in weight
when dried
Image 133 Seconds Glue
(left)
Image 14Elephant Glue
(middle)
Image 15Hot Glue Gun
(right)
3.3 SUPPORT MATERIALS ANALYSISMaterials that helped us throughout fetuccini bridge’s assignment
ii. Bucket
iii. Hook iv. Water Bottle
i. Weighing Machine
A measuring instrument in determining
the weight or mass of an object. This
was used to measure the weight of
fettuccine pieces to ensure the final
weight of our bridge did not exceed
the maximum limit.
A vertical cylinder with an open top
and a flat bottom, used to carry both
liquids and solids, aiding in the load
distribution process.
Loads used in tests conducted.Serves as a connection between the
fettuccine bridge and the bucket.
Image 16Weighing
Machine
(Top Left)
Image 17Blue Bucket
(Top Right)
Image 18Steel Hook
(Bottom Left)
Image 19Water Bottle
(Bottom Right)
3.3 STRENGTH OF MATERIAL ANALYSIS As fettuccini is the only material used for the model, its quality and
strength is required to be studied and thoroughly tested before making the
model. We aim to:
i) Achieve a high level of aesthetic value
ii) Use minimal construction material to achieve high efficiency.
2. The table (Table 1) below shows the strength of each fettuccine analysed
by applying point pressure on the middle. Different numbers, orientation and
arrangements of fettuccine were used to form the members.
Clear Span(cm)
Length Of Fettuccine (cm)
PerpendicularDistance
Weight Sustained(Horizontal Facing)
Weight Sustained(Horizontal Facing)
20
20
20
20
20
26
26
26
26
26
1
2
3
4
5
2
3
4
5
6.8
2.7
3.7
4.8
5.8
6
TABLE 1 Strength of each fettuccine analysed by applying point pressure on the middle
IMAGE 20 The loads (and reactions) bend the fettuccine and try to shear through it.
3. The strength of one fettucine appears to be lower when faced horizontally than
when it is faced vertically from 1 stick to 4 sticks. However, after 5 sticks, results turned
out to be the opposite. In conclusion, the greater the area exposed relative to its volume,
the weaker the fettuccine member is in resisting strains and stresses (The easier it is for
the member to break apart)
DIRECTION OF FORCES DIRECTION OF FORCES
4. From the result, we decided to use fettuccine members of 1 to 4 sticks with vertical
facing on the truss member that required less strength.
IMAGE 21 When the fettuccine is loaded by forces, stress and strains are created throughout the interior of the beam.
TESTING ON SINGLE MEMBER
Strength: Very strong
This design is most preferable in terms of efficiency and
workmanship
Strength: Not so strong
This is an effective design with minimal human error
IMAGE 22 I-Beam
IMAGE 23 Layerrings
4.0 B R I D G E A N A LY S I S “Studying d i fferent k ind of br idges g iv ing answer to the conclus ion”
Completed fettuccine models were put to a test. The main aim of this test is to allow the bridge to withstand the greatest load but a minimum load was set initially. This is used to identify the model with the greatest potential to be constructed for the final bridge. The series of test shows the ups and downs on the bridges constructed. Through each test, considerations were made and adapted in the new bridge and consecutively. A total of seven tests were conducted prior to making the final bridge.
4.1 MISSION
4.1.1 BRIDGE TESTING ONE
Details of the Bridge:Height and width = 750mm (width)
Length (top chord) = 600mmLength (bottom chord) = 750mm
Weight of this bridge = 125gMaximum load = 2350g
Efficiency = (2.350kg)^2 / 0.125kg = 44.18
ANALYSIS The bridge did not bend or twist as weight is gradually added.
Nevertheless, only the hook support broke when load reached at 2350g. The bridge holds it form and position.
CONSIDERATION: -
improve on the hook support
BRIDGE TEST ONE
IMAGE 24 IMAGE 25
IMAGE 26 IMAGE 27
IMAGE 28
Image 24First Part
Image 25Second Part
Image 26Third Part
Image 27Fourth Part
Image 28Fifth Part
4.1.2 BRIDGE TESTING TWO
Details of the Bridge:Height and width = 750mm (width)
Length (top chord) = 600mmLength (bottom chord) = 750mm
Weight of this bridge = 125gMaximum load = 2430 g
Efficiency = (2.430kg)^2 / 0.125kg = 47.24
ANALYSIS After the failure of the previous hook support, we improvised and came up with a different hook support design. A cross-bracing support was added. This support is able to withstand up to 2.4kg until the hook support broke. The failure of this bridge is only at the hook support. Meanwhile, the bridge
retained its form and did not collapse.
CONSIDERATION: -improve on the hook support
IMAGE 29 IMAGE 30
IMAGE 31 IMAGE 32
BRIDGE TEST TWO
Image 29First Part
Image 30Second Part
Image 31Third Part
Image 32Fourth Part
4.1.3 BRIDGE TESTING THREE
Details of the Bridge:Height and width = 750mm (width)
Length (top chord) = 600mmLength (bottom chord) = 750mm
Weight of this bridge = 130gMaximum load = 8100g
Efficiency = (8.100kg)^2 / 0.130kg = 504.69
ANALYSIS The hook support was rectified and an I-beam replaces the
horizontal support. The bridge remains stable has load is gradually added. The hook support did not break this time but however, the bottom
chord snapped causing the whole bridge to collapse.
CONSIDERATION: -Add support on the top & bottom chord
IMAGE 33 IMAGE 34
IMAGE 35 IMAGE 36
BRIDGE TEST THREE
IMAGE 37
Image 33First Part
Image 34Second Part
Image 35Third Part
Image 36Fourth Part
Image 37Fifth Part
4.1.4 BRIDGE TESTING FOUR
Details of the Bridge:Height and width = 750mm (width)
Length (top chord) = 600mmLength (bottom chord) = 750mm
Weight of this bridge = 130gMaximum load = 700 g
Efficiency = (0.700kg)^2 / 0.130kg = 3.77
ANALYSIS This bridge was an exact replicate of the previous bridge but blown
up to a bigger scale to fit the requirements of a 750mm clear span. Allmembers remain the same thickness and also the use of I beams as the hook
support.The failure of this bridge was identified as workmanship effort. The bridge twisted as load is gradually added up to the point the sides
broke causing the whole bridge to collapse. This is due to the bottom chord not being straight when constructing.
CONSIDERATION: -- Improve workmanship
- Ensure bottom chord is straight and sits balanced
on the table.
IMAGE 38 IMAGE 39
IMAGE 40 IMAGE 41
BRIDGE TEST FOUR
IMAGE 42
Image 38First Part
Image 39Second Part
Image 40Third Part
Image 41Fourth Part
Image 42Fifth Part
4.1.5 BRIDGE TESTING FIVE
Details of the Bridge:Height and width = 85mm (width)
Length (top chord) = 843mmLength (bottom chord) = 850mm
Weight of this bridge = 130gMaximum load = 2700g
Efficiency = (2.700kg)^2 / 0.130kg = 56.08
ANALYSIS All members remain the same thickness and use of I beams as the
hook support. This bridge failed as the bottom chord snapped.However, the hook support did not break and retain its form.
CONSIDERATION: -Strengthen the bottom chord
IMAGE 43 IMAGE 44
IMAGE 45 IMAGE 46
BRIDGE TEST FIVE
IMAGE 47
Image 43First Part
Image 44Second Part
Image 45Third Part
Image 46Fourth Part
Image 47Fifth Part
4.1.6 BRIDGE TESTING SIX
Details of the Bridge:Height and width = 110mm from highest point to bottom (height)
775 (width)Length (top chord) = 881mm
Length (bottom chord) = 850mmWeight of this bridge = 273gMaximum load = 2825 units
Efficiency = (2.825kg)^2 / 0.273kg = 29.23
ANALYSIS After doing the precedent studies, we decided to try out another bridge
with a different design. This bridge is steady and strong. However, the failure of this bridge happens on the hook support which is a cross-braced design. Upon
adding load up to 2.8kg, the hook support snaps. However the members of bridge remained intact. The bridge remained its form.
CONSIDERATION: -Straigthen its hook support.
IMAGE 48 IMAGE 49
IMAGE 50 IMAGE 51
BRIDGE TEST SIX
IMAGE 52
Image 48First Part
Image 49Second Part
Image 50Third Part
Image 51Fourth Part
Image 52Fifth Part
4.1.7 BRIDGE TESTING SEVEN
Details of the Bridge:Height and width = 110mm from highest point to bottom (height) 775 (width)
Length (top chord) = 881mmLength (bottom chord) = 850mm
Weight of this bridge = 280gMaximum load = 5315g
Efficiency = (5.315kg)^2 / 0.280kg = 100.89
ANALYSIS The bridge has same design as the previous bridge. However, the only
difference is the hook support. The conclusion was drawn based on theprevious tests that a hook support made from multiple layers of fetuccini
is not as strong as a hook support composed of I beams. In this test, the bridge withstand up to 5.3kg and “crack” sound can be heard. The failure of this bridge happens when one of the chord could not
take the load causing the whole bridge to collapse. However, the hook support did not deform.
CONSIDERATION: -Strengthen the supports on the side as it fails to hold
up the bridge.
IMAGE 53 IMAGE 54
IMAGE 55 IMAGE 56
BRIDGE TEST SEVEN
IMAGE 57
Image 53First Part
Image 54Second Part
Image 55Third Part
Image 56Fourth Part
Image 57Fifth Part
5.0 F I N A L M O D E L T E S T I N G“The h ighl ight of th is ass ignment”
5.1 FINAL DESIGN OF OUR FETTUCCINE BRIDGE
Details of the Bridge: Height and width = 83mm(height)
52mm (width)Length (top chord) = 753mm
Length (bottom chord) = 866.75mmWeight of this bridge = 203g
Maximum load = 3.2kg
ANALYSIS Efficiency = (max load)2/ Weight of bridge = 10.24/0.203 = 50.44% efficient.
Although many considerations were taken into the final bridge design, the total weight of the bridge once completed was heavier than previous models, and we
feared a lower efficiency than 50%. However, during testing, we realised the final bridge design was a rigid and strong one and could have taken more load if
workmanship had been precise and accurate, unfortunately, with fettuccini sticks we cannot guarantee that. It was one part of the bottom chord that snapped away
and we strongly believe it was due to the inconsistency in the overlapping method of fettuccini pieces making up the chords.
CONSIDERATION
If we were to carry out a second final test, we would shorten the total length of the chord to reduce some weight and add rigidity. We would also remove all the top (single layer)
and bottom (double layer) horizontal connecting members and replace them with a single layer x-cross bracing from one façade to another. We believe this would drop down the weight of our bridge by at least 30-40g, and the max load would probably be a little bit
less, but our goal is obtaining best efficiency, therefore we would expect a higher efficiency value than 50%.
IMAGE 58 IMAGE 59
IMAGE 60 IMAGE 61
FINAL BRIDGE TEST
IMAGE 62
Image 58First Part
Image 59Second Part
Image 60Third Part
Image 61Fourth Part
Image 62Fifth Part
43.88
71.00
376.50
91.1981.23
58°58°58°58°58°58°58°58°
32° 32°
58°
32° 32°
58°
32°
32°
58°
32°
58°
32°
32°
58°
32°
58°
32°
32°
58°
55°
35°
50mm
71mm
753mm
breaking point the chord is stressed to a snapping point, at the 2points shown. no other member was affected/broken.
DISTANCE AND ANGLE OF TRUSSES
EFFECT ANALYSIS
FORCE DISTRIBUTION IN TRUSS
750.00
375.00
1
2
3
45 6
7
8
9
10
25N 25N50N
1
2
3
45 6
7
8
9
10
25N 25N50N
A P P E N D I X
AIM
We need to identify 6 Case Study from the activity that our lecturers provided to help on
our understanding about truss analysis. As every case has the same load applied on it, we found out that
the Fx Fy and Momentum towards every cases has the same calculation also.
The calculations: -
∑Fx = 0
20 + 5- + 80 + Ra + RJx = 0
∑Fx = 0
150 + Rx+RJx= 0
-100+15-60-50-RJy= 0
(-RJyx 3.5) – 50(3.5) -80 (3.5) +60(6) -152(2) -20(1) + 50(8) + 100(2) = 0
RJx (3.5) = 185
RJx=52.857
150+ Ra +52.587 = 0
Ra=-202.827
To determine wether its a perfect truss: -
2J = m+3
1. 2J = 2 (a)
= 18
2. m + 3 = 15 + 3
= 18
thus,
It is a perfect truss.
DONE BY TEH KAH KHEN
CASE 1
DONE BY NUR ADILA ZAAS
CASE 2
CASE 3
DONE BY ANDREA LEE
DONE BY TREVOR NJC HOEREAU
CASE 4
CASE 5
DONE BY KENN WONG
CASE 6
DONE BY ROUANNE
CASE 1
CASE 2
CASE 3
CASE 4
CASE 5
CASE 6
25N 25N50N
25N 25N50N
25N 25N50N
25N 25N
50N
25N 25N50N
25N 25N50N
25N 25N50N
25N 25N50N
25N 25N50N
25N 50N
25N 25N50N
25N 25N50N
25N 25N50N
1
2
3
45 6
7
8
9
10
25N 25N50N
25N 25N50N
COMPRESSION AND TENSION ANALYSISAnalyzing all the cases in general, it is visible which is the most efficient amongst the 6.
Firstly, let us imagine all these cases are acting out simultaneously. Secondly, an important point to note is that the more force there is on an individual member, the more stress it is undertaking, hence that member will break more easily.
For example, looking at case 2, the vertical column takes the most force of 210KN and will fail first. And in this case, is the least efficient.
In case 3, the vertical column that transfers 150KN would collapse followed by the top member that transfers 202.86KN as the force is not distributed evenly to the nearby members.
Case 4 and 5 have two end vertical members transferring zero load, hence making those members inactive and useless in this system. However case 4 would collapse before case 5 because the second column from the left holds more weight than the 5th case, making case 5 truss system more efficient than case 4 due to the weight distribution.
In case 6, the two top horizontal members will collapse first as they are transferring the most load. Case 6 is of moderate efficiency compared to case 4 and 5. However, case 1 is the most efficient as there is an obvious better distribution of load.
Analyzing all the cases in general, it is visible which is the most efficient amongst the 6.
Firstly, let us imagine all these cases are acting out simultaneously. Secondly, an important point to note is that the more force there is on an individual member, the more stress it is undertaking, hence that member will break more easily.
For example, looking at case 2, the vertical column takes the most force of 210KN and will fail first. And in this case, is the least efficient.
In case 3, the vertical column that transfers 150KN would collapse followed by the top member that transfers 202.86KN as the force is not distributed evenly to the nearby members.
Case 4 and 5 have two end vertical members transferring zero load, hence making those members inactive and useless in this system. However case 4 would collapse before case 5 because the second column from the left holds more weight than the 5th case, making case 5 truss system more efficient than case 4 due to the weight distribution.
In case 6, the two top horizontal members will collapse first as they are transferring the most load. Case 6 is of moderate efficiency compared to case 4 and 5. However, case 1 is the most efficient as there is an obvious better distribution of load.
CONCLUSION
R E F E R E N C E S
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Image 10 : retrieved from https://grocermart.com/image/cache/data/SanRemo1/fettuccine-1800x1800.jpg
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Image 17 : retrieved from http://www.axis-cleaningsupplies.co.uk/media/catalog/product/cache/1/image/9df78e-ab33525d08d6e5fb8d27136e95/u/h/uhbb1030l_10ltr_bucket_blue.png
Image 18 : retrieved from http://www.preserveshop.co.uk/images/stainless-steel-hanging-hook.jpg
Image 19 : retrieved from http://cdn5.triplepundit.com/wp-content/uploads/2009/11/bottled-water.jpg
Image 20 : drawn by Chen Rou Anne
Image 21: drawn by Chen Rou Anne
Image 22 : drawn by Chen Rou Anne
Image 23 : drawn by Chen Rou Anne
Image 24 : photograph by Kenn Wong
Image 25: photograph by Kenn Wong
Image 26 : photograph by Kenn Wong
Image 27 : photograph by Kenn Wong
Image 28 : photograph by Kenn Wong
Image 29 : photograph by Andrea Lee
Image 30 : photograph by Andrea Lee
Image 31 : photograph by Andrea Lee
Image 32 : photograph by Andrea Lee
Image 33 : photograph by Andrea Lee
Image 34 : photograph by Andrea Lee
Image 35 : photograph by Andrea Lee
Image 36 : photograph by Andrea Lee
Image 37 : photograph by Adila Zaas
Image 38 : photograph by Adila Zaas
Image 39 : photograph by Adila Zaas
Image 40 : photograph by Adila Zaas
Image 41 : photograph by Adila Zaas
Image 42 : photograph by Adila Zaas
Image 43 : photograph by Kenny Teh
Image 44 : photograph by Kenny Teh
Image 45 : photograph by Kenny Teh
Image 46 : photograph by Kenny Teh
Image 47 : photograph by Adila Zaas
Image 48 : photograph by Adila Zaas
Image 49 : photograph by Adila Zaas
Image 50 : photograph by Adila Zaas
Image 51 : photograph by Adila Zaas
Image 52 : photograph by Kenny Teh
Image 53 : photograph by Kenny Teh
Image 54 : photograph by Kenny Teh
Image 55 : photograph by Kenny Teh
Image 57 : photograph by Kenny Teh
Image 58 : photograph by Kenny Teh
Image 59 : photograph by Kenny Teh
Image 60 : photograph by Kenny Teh
Image 61 : photograph by Kenny Teh
Image 62 : photograph by Kenny Teh
Image 63 : photograph by Kenny Teh
Image 64 : photograph by Kenny Teh
Image 65 : photograph by Kenny Teh
Image 66 : photograph by Kenny Teh
Image 67 : photograph by Kenny Teh
REFERENCE LISTS
Kozel, S. (1997, August 14). Francis Scott Key Bridge (Outer Harbor Crossing). Retrieved October 8, 2014, from http://www.roadstothefuture.com/Balt_Outer_Harbor.html
Overview of Forth Bridge. (2014, January 1). Retrieved October 8, 2014, from http://www.scottish-places.info/features/featurefirst1053.html
Sangree, R. (2014). An Engineer’s Guide to Baltimore. Retrieved October 8, 2014, from http://www.ce.jhu.edu/baltimorestructures/Index.php?location=Francis%20Scott%20Key%20Bridge
T H Kwok, D. (2009, April 1). ANALYSIS OF FRANCIS SCOTT KEY BRIDGE (BALTIMORE). Retrieved October 8, 2014, from http://www.bath.ac.uk/ace/uploads/StudentProjects/Bridgeconference2009/Papers/KWOK.pdf
Triangulation & measurements at the Forth bridge; reprinted, with additions, from “The Engineer.” (1887, January 1). Retrieved October 8, 2014, from http://www.worldcat.org/title/triangulation-measurements-at-the-forth-bridge-a-description-of-the-measurements-of-a-base-line-the-triangulation-of-stations-therefrom-and-the-setting-out-of-the-foundations-and-portions-of-the-steel-work-reprinted-with-additions-from-the-engi-neer/oclc/123250114
BOOK SIZE REFERENCE DO NOT IN-CLUDE THIS
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