Fettucine Truss Bridge Report
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Transcript of Fettucine Truss Bridge Report
FETTUCCINE TRUSS BRIDGE
Kimberly Wong 0315145
Lai Chi Mun 0319463
Lau Wei Ling 0315389
Lim Chin Yi 0315627
Lim Shu Ting 0320102
Architecture Semester 4
March 2016 Intake
Building Structures
ARC 2523
2
Content
No.
Page
1.0 Introduction 3
1.1 Precedent Studies 5
2.0 Analysis of Material Strength
Modular test
Truss test
9
3.0 Construction of Bridge 13
4.0 Bridge Testing 14
5.0 Structural Analysis of the bridge 18
6.0 Conclusion 24
7.0 References 25
8.0 Appendix 26
3
1.0 Introduction
In a group of 5, we were assigned to construct a fettuccine truss bridge. To understand the
tension and compressive strength of truss system, we were to construct a perfect truss bridge.
Research and preparations were done before construction of the truss bridge.
To conduct the testing and construction of fettucine truss bridge, materials and equipment
were prepared:
A) Construction Material
Different types of materials are prepared and tested. The material with the best compressive strength and
adhesive strength are chosen for the construction of fettuccine truss bridge.
Different brands of Fettuccines
San Remo Fettuccine
Kimball Fettuccine Prego Fettuccine
Different types of glues
UHU glue Superglue PVC Glue Hot glue
4
B) Construction Equipment
The following equipment is used to construct the fettuccine truss bridge.
Sand paper Cutter and cutting mat
For the initial stage of construction, cutter is used to cut the fettucine. The edge of the fettucine members
is sand by using sand paper to make it fit to the flat surface.
C) Weight Testing equipment
S hook Bucket Water as weight
The load test was carried out by hanging the s hook to the middle of the fettuccine truss bridge. The other
end of S hook will hang a bucket. Water that are measured to a certain weight will be added into the
bucket slowly.
Adhesive Technique
By applying point to
point technique, the
adhesive strength is
compromised. It can
support only 475g of
compression force.
By applying in a line,
the adhesive strength is
much better. It can
withstand 1537g of
compression force.
5
1.1 Precedent Study
Introduction to Truss Bridge
Truss bridge is the bridge that uses truss as main element and they form into triangular unit when
connected. Truss bridge structure is used widely due to its rigidity and it can distribute loads from a single
point to a much wider area (Truss Bridge - Types, History, Facts and Design, n.d.). The bridge members
are usually stresses from tension and compression force. Truss bridges can be categorized into 2 group,
the perfect truss and imperfect truss.
Perfect Frame
Frames that can be analysed to get the internal member forces and external support reactions through the
three conditions of static equilibrium (Shiva, 2015). The formula N=2j-3 can be used to determine a
perfect structure where ‘N’ is the number of members and ‘j’ is the number of joints.
Waddell A Truss
Flat Pratt Truss
Howe Truss
Warren Truss
Warren With Vertical Truss
6
Fredericktown Bridge
Fredericktown Bridge is built in 1840 to 1844 and closed in 1907 and it collapsed 20 years later. This
bridge is an 1893 truss bridge built by the Penn Bridge company of nearby Beaver Falls, PA. It was
rehabilitated in 2004 and the deck replaced.
7
Warren Truss
The bridge that is with an equilateral truss, all panel lengths and diagonals are of equal length creating a
series of equilateral triangles. When the panel lengths are shorter than the equal length diagonals, it was
sometimes called an isosceles or isometric truss.
Warren Truss with verticals
As the length increases so does the height of the truss, compression is acted towards the members and
bracing is needed to minimize buckling and to provide support for the vertical direction. The verticals are
position from the lower chord panel points up to the midpoint of the chord member directly above. The
deck structure stringers will lengthen in order to help the heavier members or any addition of verticals
from the top chord panel points dropping down, to be able to shorten panel lengths.
8
2.0 Analysis of Material Strength
1. Modular Test
A) Material test using different brands of fettuccine and glue.
The test was done by stacking 3 pieces of fettuccine together with
different types of glues. This is repeated with different brands of fettuccine.
From the result of the test, San Remo brand of fettuccine is the strongest
among the 3 types of fettuccine while superglue has the strongest bonding
strength. The combination of San Remo fettuccine with superglue can
withstand 600g of load.
Load Test
Brand Glue 100g 200g 300g 400g 500g 600g 700g 800g
San Remo PVA
Superglue
Hot glue
UHU
Prego PVA
Superglue
Hot glue
UHU
Kimball PVA
Superglue
Hot glue
UHU
9
B) Compression strength test
Force exerted
San Remo 0.50N
Prego 0.27N
Kimball 0.25N
Compression strength is tested for different brand of fettuccine. The test is done by exerting force
on fettuccine placed vertically on a weight balance. From the test, San Remo Fettucine has the best
compression strength.
The compression strength is further tested by doing test on different number of layers of
fettuccine
Force exerted Force exerted
1 layer of Fettuccine
0.45N
3 layers of I beam
14.67N
2 layers of Fettuccine
2.68N
4 layers of I beam
18.93N
3 layers of Fettuccine
11.11N 5 layers of I beam
47.73N
The 5 layers of I beam has the best structural strength. Thus, it is used as the bottom layer of the
truss structure where it will carry the total weight of the structures.
10
2. Truss Test
A) Trusses with different vertical members
The truss is tested with different vertical members with various height. The horizontal members
are kept constant. The diagonal member length is dependent on the vertical members’ height.
Height of Truss Efficiency, E= (𝐿𝑜𝑎𝑑
𝑀𝑎𝑠𝑠 𝑜𝑓 𝑇𝑟𝑢𝑠𝑠)
5cm 39.68
6cm 32.61
7cm 23.64
The truss with 5cm vertical members is stronger compared to 6cm and 7cm, it can withstand 250g
of load.
From the height test, all of the trusses failed and collapsed at the similar parts of the members.
Referring to the diagram below, the truss members will be strengthen by using double layers for the next
test.
Load Test
San Remo Fettuccine 25
0g
50
0g
75
0g
10
00
g
12
50
g
15
00
g
17
50
g
20
00
g
22
50
g
25
00
g
27
50
g
30
00
g
5cm (63g)
6cm (69g)
7cm (74g)
11
B) Different design of trusses
Load Test
Trusses Design 25
0g
50
0g
75
0g
10
00
g
12
50
g
15
00
g
17
50
g
20
00
g
22
50
g
25
00
g
27
50
g
30
00
g
6cm (69g)
Warren with verticals
6cm (68g)
Howe
6cm (71g)
Pratt
Types of Truss Efficiency, E= (𝐿𝑜𝑎𝑑
𝑀𝑎𝑠𝑠 𝑜𝑓 𝑇𝑟𝑢𝑠𝑠)
Warren with verticals 32.61
Howe 22.05
Pratt 24.64
With the members of same height and length, different types of trusses were tested. In a nutshell,
Warren truss with verticals is the strongest among the 3 trusses, it has the highest efficiency.
12
3.0 Construction of Bridge
Step 1
The bottom chord is built by a few stacking
layers of fettuccine to form I beam.
Step 2
Vertical members of the truss are attached to the
bottom chord from the middle.
Step 3
Top chord of the truss was then attached to the
vertical members.
Step 4
The remaining vertical members are added to the
truss bridge.
Step 5
The diagonal members are added into the truss
members.
Step 6
Step 1 to step 5 is repeated to build the opposing
side of the truss bridge.
Step 7
The horizontal members that connects both sides
of the truss bridge are added together with the core
at the bottom chord.
Step 8
Lastly, the horizontal members are also added at
the top chord.
13
4.0 Bridge Testing
1.
Bridge Width=5cm
Load=2500g
Efficiency
=2500g/63g
=39.68
The bridge broke at the
middle part.
No I beam was used in
the construction.
2.
Bridge Width=5cm
Load=2250g
Efficiency
=2250g/69g
=32.61
Different height of bridge
used in 1st and 2nd bridge
to test their strength.
3. Bridge Width=5cm
Load=1750g
Efficiency
=1750g/74g
=23.65
Different designs of
trusses were constructed.
Bottom chord was
changed to I beam
450mm
50mm
450mm
60mm
450mm
50mm
14
4.
Bridge Width=4cm
Load=5000g
Efficiency
=5000/70
=71.43
Warren truss bridge are
added with I beam.
Some vertical members
are double layers.
Only the middle member
that is hanging hook
breaks.
5.
Bridge Width=4cm
Load=5800g
Efficiency
=5800/77
=75.32
More vertical and
diagonal truss members
are added.
Some vertical members
are double layers.
Only the middle member
that is hanging hook
breaks.
6.
Bridge Width=4cm
Load=4800g
Efficiency
=4800/70
=68.57
6 horizontal members
support at bottom cord.
The middle part of the
truss breaks in halves.
450mm
40mm
450mm
50mm
40mm
450mm
15
7.
Bridge Width=4cm
Load=3000g
Efficiency
=3000/70
=42.86
The I beam was left
overnight and became
brittle.
The members to hang S
hook is too small. Thus,
the S hook breaks the
bridge.
8.
Bridge Width=4cm
Load=3000g
Efficiency
=3000/70
=42.86
The I beam was left
overnight and became
brittle.
The warren truss ends
before the table edge.
Hence, the truss breaks
easily.
410mm
40mm
410mm
50mm
16
9.
Bridge Width=4cm
Load=5000g
Efficiency
=5000/7
=71.43
The truss breaks because
of S hook exerting force
horizontally.
Considered increase the
width of members to
place S hook.
10.
Bridge Width=4.5cm
Load=11200g
Efficiency
=11200/71
=157.75
The span of gap to place
the bridge is reduced
from 350mm to 300mm
The S hook is not directly
hang at the truss member.
Ropes are used to tie on
the truss and hanged the
S hook.
The truss bridge break at
the members that hanged
S hook.
50mm
410mm
410mm
50mm
17
5.0 Structural analysis of the Bridge
Truss system of the final model bridge
18
19
20
21
22
The internal forces for all the vertical members are 0. However, the horizontal and diagonal members are
either in tension or compression. From conclusion, the vertical members are redundant in the truss system
with the load exerted at point M.
23
6.0 Conclusion
Throughout the whole project, we have constructed 9 experimental fettuccine truss bridges and one final
fettuccine truss bridge. For every structural failure, we investigated the construction of fettuccine truss
bridge to improvise the strength of the fettuccine truss bridge. From what we learnt from experience, we
are able to construct the best fettuccine truss bridge with the highest efficiency. Our final model achieves
an efficiency of 157.75 and it is able to withstand 11kg of load.
During the process, we are able to learn knowledge and constantly improve our understanding on
truss bridges. This project had trained us to be attentive to the details of every test and construction. We
learnt about the different types of perfect trusses, load distributions and also able to identify the types of
internal forces in the truss members. Other than that, we also realized that every mistake and failure are
the stepping stones for our next success.
In a nutshell, this project is an eye opener to all of us. We learnt a lot about structural design of a
bridge where both aesthetical and structural value are equally significant. The understanding of structural
system is definitely beneficial to all of us in the future.
24
7.0 References
Boon, G. (2011, April 1). Warren Truss. Retrieved May 2, 2016, from
http://www.garrettsbridges.com/design/warren-truss/
How to Build a Spaghetti Bridge. (2016). Retrieved May 1, 2016, from
http://www.wikihow.com/Build-a-Spaghetti-Bridge
Mettem, C. (2011). Timber bridges. Abingdon, Oxon: Spon Press.
Schweige, P. (1999, September 19). Fettuccini Physics Contest. Retrieved April 24, 2016, from
http://teachertech.rice.edu/Participants/pschweig/lessons/BridgeProject/pastacontest/page4.html
Shiva. (2015, May 22). Perfect Truss & Imperfect Truss. Retrieved May 12, 2016, from
http://semesters.in/perfect-truss-imperfect-truss/
Tension and Compression. (2016). Retrieved April 25, 2016, from
http://science.howstuffworks.com/engineering/civil/bridge2.htm
Truss Bridge - Types, History, Facts and Design. (n.d.). Retrieved May 12, 2016, from
http://www.historyofbridges.com/facts-about-bridges/truss-bridge/
Warren Truss Bridge | Definition | Advantages and Disadvantages. (n.d.). Retrieved April 25,
2016, from http://www.transtutors.com/homework-help/civil-engineering/truss-
application/warren-truss/