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.

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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/