Building Structure by Justinetlt

ARC 2523 Project 1 Fettuccine Truss Bridge

ARC 2523 BUILDING STRUCTURE PROJECT FETTUCCINE BRIDGE REPORT

Chan Pin Qi

0314676

Lim Yee Qun

0319121

Te Li Theng

0314198

Liew Qiao Li

0315671

Woo Wen Jian 0315123

9th October 2015

ARC 2523 Project 1 Fettuccine Truss Bridge

TABLE OF CONTENTS CHAPTER 1: INTRODUCTION 1.1 Introduction to the Project 1.2 Aim and Objective 1.3 Scope 1.4 Limitations 1.5 Equipment and Materials Used 1.6 Testing of Materials 1.7 Methodology 1.8 Schedule of Work

3 4 5 5 6-9 10 11-12 13

CHAPTER 2: PRECEDENT STUDY 2.1 Wadell “A” Truss Bridge, Parkville, Missouri

2.2 Design Strategies and Load Distribution 2.3 Trusses and Connection

14 15 16-17

CHAPTER 3: EXPERIMENTATION AND PROGRESS 3.1 Bridge Truss Design 1 vs Bridge Truss Design 2 3.2 Bridge Truss Design 3 3.3 Bridge Truss Design 4 3.4 Bridge Truss Design 5

18-21 22-23 24-25 26-27

CHAPTER 4: FINAL BRIDGE 4.1 Amendments 4.2 Top & Bottom Chord 4.3 Core Horizontal Element 4.4 Vertical & Diagonal Truss 4.5 Joints 4.6 Members & Connection of Fettuccini Bridge 4.7 Joint Analysis 4.8 Final Model Making 4.9 Final Bridge Test and Load Distribution 4.10 Calculation of Distribution of Forces for Final Bridge

28 29 30 31 32 33 34-39 40-44 45 46-50

CHAPTER 5: REFERENCES

CHAPTER 6: INDIVIDUAL CASE STUDIES 6.1 Case Study 1: Chan Pin Qi 6.2 Case Study 2: Lim Yee Qun 6.3 Case Study 3: Te Li Theng 6.4 Case Study 4: Liew Qiao Li 6.5 Case Study 5: Woo Wen Jian

52-55 56-59 60-63 64-67 68-71

ARC 2523 Project 1 Fettuccine Truss Bridge

Chapter 1: Introduction 1.1 Introduction to the Project This project is commissioned by AR2523: Building structures. In a group of five, students are assigned to build a bridge using fettuccine as the materials for the bridge truss members. The weight of the bridge must not be more than 80g, but is required to carry a much larger weight for an extended period of time. The clear span of the bridge must be at least 350mm.

With many unknown variables, including its compression and tension capabilities, students are asked to experiment with different kind of methods of joint and designs to determine the best design for a bridge. Students will learn to explore truss members using different arrangements to achieve the best performance and how to build the prefect truss. Students are to find out the strength of each design by testing out and find out its tension and compression forces.

Students will then apply the knowledge of calculating the moment force, reaction force, internal force and force distribution of a truss. By identifying all these forces, students will be able to enhance their design by determining which members need amendment in order to make it stronger.

This report contains information regarding the students' analysis and documentation of the experimentation with several fettuccine truss bridge designs. Individual case studies are also in these reports, along with insight and suggestions for improvement.

ARC 2523 Project 1 Fettuccine Truss Bridge

1.2 Aim and Objective The aim of this project is to develop students' understanding of force distribution in a truss. It also aims to teach that different design and construction methods can alter the efficiency in withstanding loads.

The objective of this project is to discover the most efficient bridge design with fettuccine as material in regards to its tension and compression capabilities. Students are also to learn how different forces (tension and compression) to affect a bridge efficiency, especially considering fettuccine as a relatively weak materials.

Also, the project aims to teach students to build a perfect truss, a truss design with high aesthetic value, and at the same time with a minimal construction material that could withstand a high amount of loads.

ARC 2523 Project 1 Fettuccine Truss Bridge

1.3 Scope The scope of this project was to use only fettuccine as the construction material. The bridge constructed is required to have a clear span of 350mm and a weight lesser than 80g. Prior to deciding the final truss bridge design, process such as preparing precedent studies, material durability test, model making and load testing process were conducted. This is to explore which ways that could enhance the bridge design to hold more loads.

1.4 Limitations

Our main limitation was that the weight of the bridge must not exceed the range of 80grams. This caused us to carefully study how do the forces distribute in the bridges that we designed and how could we enhanced the strength of the bridge design and at the same time, to minimize the construction materials. Consequently, a lot of designs were produced in order to get the perfect design.

ARC 2523 Project 1 Fettuccine Truss Bridge

1.5 Equipment and Materials Used San Remo Fettuccine: San Remo brandâ&#x20AC;&#x2122;s fettuccine is the best in term of cost to compression strength compared to the other brands during the material durability test.

Cutting knife:

Cutting knife was used to cut the fettuccine to pieces during the making of the bridge truss to achieve the precision that is close to what we wanted to design.

3-second glue:

Used when gluing the bridge joint together. It has great adhesion strength that allows fettuccine to join together in about 3-5 seconds.

ARC 2523 Project 1 Fettuccine Truss Bridge

Cutting mat:

Used to protect the table surface when cutting the fettuccine as well as the edges of the fettuccine.

Steel Ruler:

Used to measure the length and marking on each fettuccine before cutting it.

Sandpaper:

Used to smoothen the edges of the fettuccine after cutting and before gluing.

ARC 2523 Project 1 Fettuccine Truss Bridge

500 ml water bottle: Used as load during the load testing of the bridge. It is much more faster to test out the designs this way.

Thin ropes:

Used to hang both centre components and S hook together. The force distributed is much more even compared to using the s hook to the centre component

Phones:

Used to record and document the results of each of the designs during the test.

ARC 2523 Project 1 Fettuccine Truss Bridge

S-hook:

Used to connect the rope and the bucket.

Electronic balance:

To measure the weight of the bridge truss and the weight of the load applied on the bridge.

Bucket:

Used as a load by filling it up with water during the load testing.

ARC 2523 Project 1 Fettuccine Truss Bridge

1.6

Testing of Materials

Testing of durability of construction materials Brands

Analysis (durability test with 10 strands of fettuccines)

Kimball

Withstand up to 4 cups of water

Prego

Withstand up to 5 cups of water

San Remo

Withstand up to 6 cups of water

(CHOOSEN as construction materials)

Testing of the adhesive strength Types of adhesive

Analysis

UHU Glue

-Slowest solidify time duration (30seconds) -Average strength efficiency -Weak bond efficiency

3-Second- Glue

-Fastest solidify time duration (3-5 seconds)

(CHOOSEN as adhesive -High strength efficiency materials) -High bond efficiency -Causes bridge to be brittle after leaving it for a day

ARC 2523 Project 1 Fettuccine Truss Bridge

1.7

Methodology

Step 1: Prior to designing, a precedent study were conducted to understand how a truss bridge works and how does force distribute in the bridge. Then we tested out different brands of fettuccine as well as different brand of adhesives, this is to sort out which is the best and most cost effective among all of the choices in the market.

Step 2: We first understand how forces act on a fettuccine. We tested the tension and compression strength of the fettuccine, we simply tried to pull the ends (tension) and push them together (compression). We found that the compressive strength of fettuccine is weak, while it has great tensile strength.

Step 3: Upon understanding from the precedent study, we sketched a few possible designs for an efficient perfect truss bridge. We had to be sure to design it for a clear span of 350mm (leaving 50mm on the sides to hoist up on the table).

Step 4: Proceed to build the bridge. The elevations of the bridges were cadded in AutoCAD and then printed out. This is to ensure precision when we cut and join the fettuccines together. Then, we did a quality check on the packets of fettuccines and sorted out the straight ones and the twisted ones.

Step 5: Then, pen knives are then used to slice the fettuccine members to the correct length. To join them together laterally, the first layer contain two equally sized fettuccines and connected with a second layered fettuccine that connects both of them, while the sides of the second layered are filled with fettuccines of desired length. Also we did made sure the joints did not line up, so as to avoid breakage.

Step 6: Using three-second glue, the members are join together. Alignment is also crucial in this process, as is craftsmanship. Joints must fit together perfectly, without unnecessary gaps between them. Amendments can hardly be done as 3-second-glue has a very strong adhesive strength. Thus, precision is crucial in this step.

ARC 2523 Project 1 Fettuccine Truss Bridge

Step 7: After waiting for the three-second-glue dry properly (at least 5 minutes), the bridges are ready to be test out. To test the bridge, we set two tables (of equal height) exactly 350mm apart, and set the bridge in the middle. In preparation for the bridge testing, we must first weight the bridge to see how far above or below the 80 g mark we are. After documenting the weight, the S hook and bucket are weight to calculate the total weight of the load that will be hung from the bridge.

Step 8: A thin rope is tied on the midpoint or centre point of the bridge to the S hook, the S hook is then used to connect the thin rope and the bucket handle. The bucket does not elevate too far above from the ground, this is to avoid the bucket to break upon falling impact.

Step 9: Using a 500ml water bottle (filled to the very top), water is slowly poured into the bucket. As load is being added, the bridge is checked for any deformities. As the fettuccine begins to deform, the points where the bridge are the weakest will then be noted down. We then continued pouring until the bridge broke. Using the 500 ml bottle as a reference, we calculated how much water was poured in.

Step 10: Based on the observation, the strength of the bridge is studied and the design is refined accordingly by enhancing its weak points. We strengthened the parts that deformed quickly and parts that snapped upon heavy loads are applied to the bridge.

Step 11: Step 4 to step 10 were repeated to upgrade and refine the design of the fettuccine bridge until the design can hold a desirable loads as well as a mass that is lesser than 80g.

ARC 2523 Project 1 Fettuccine Truss Bridge

1.8 Schedule of Work 9th Sept 2015

Experimentation on the most durable brand of fettuccine and the adhesive with the most strength. Research and preliminary sketches, discussion of possible design ideas for Bridge#1

15th Sept 2015

Deciding on the design of the first bridge to be built Research and preliminary sketches, discussion of possible design ideas for Bridge#2

19th Sept 2015

Building of Bridge#1 and Bridge#2

23th Sept 2015

Discussion of the weakness of Bridge#1 and Bridge#2 on its designs. Joints have the most weakness. Discussed possible method to join members together. Introduced I-beams to designs.

26th Sept 2015

Research and preliminary sketches, discussion of possible design ideas for Bridge#3. Building of Bridge#3. Testing of Bridge#1, Bridge#2 and Bridge#3. Research and preliminary sketches, discussion of possible design ideas for Bridge#4.

27th â&#x20AC;&#x201C; 28th Sept 2015

Building of Bridge#4. Testing of Bridge#4. Research and preliminary sketches, discussion of possible design ideas for Bridge#5. Building of Bridge#5. Testing of Bridge#5. Decided on Bridge#5 as the design for assessment. Building of Bridge#6 Assessment of Bridge#6

ARC 2523 Project 1 Fettuccine Truss Bridge

Chapter 2: PRECEDENT STUDIES 2.1 Wadell “A” Truss Bridge, Parkville, Missouri.

Figure 2.1.1 Elevation of Waddell "A" Truss Bridge

Other name: Linn Branch Creek B ridge Location: English Landing Park, Parkville History: The Waddell “A” Truss Bridge also known as Linn Branch Creek Bridge is located in Parkville, Missouri. The bridge was formerly built for the Quincy and Kansas City Railway in 1898. In 1939, it had been abandoned; however it was converted into a highway bridge in 1953. In order to make room for Smithville Reservoir, it had been disassembled by the U.S. Army Corps of Engineers in 1980, but the bridge was then re-assembled in English Landing Park, Parkville in 1987 and open only for pedestrian. 14

ARC 2523 Project 1 Fettuccine Truss Bridge

2.2 DESIGN STRATEGIES AND LOAD DISTRIBUTION

Figure 2.2.1 Load distribution diagram

Waddell “A” truss bridge was documented by the Historic American Engineering Record. It was designed by the well-known American Engineer John Alexander Low Waddell. Waddell stated that, “the truss was considered as an economical short-span, pin connected structure and without excessive vibration, the bridge is capable in supporting heavy traffic. “ The members along the top chord which supporting downward forces are in compression whereas the members along the bottom chord are in tension. While the members joining the top and bottom chords which are the web members, they may be in tension or compression due to the different angles used and the different distribution of loads.

ARC 2523 Project 1 Fettuccine Truss Bridge

2.3 Trusses and Connections

Figure 2.3.1 Side views of the bridge showing its abutment and top view of its detail view of its lateral bracing.

Figure 2.3.2 Detail of Truss Connections and Members by John Alexander Waddell

ARC 2523 Project 1 Fettuccine Truss Bridge

Figure 2.3.3 Detail of Truss Connections and Members by John Alexander Waddell

Figure 2.3.4 Detail of Truss Connections and Members by John Alexander Waddell

ARC 2523 Project 1 Fettuccine Truss Bridge

Chapter 3: EXPERIMENTATION AND PROGRESS 3.1 Bridge Truss Design1 vs Bridge Truss Design2 Through our research, we decided to use the style of the Waddell “A” Truss Bridge as our guideline on our bridge truss design. As to kick start our experiment, we started with making 2 different designs of Waddell “A” Truss Bridge to identify which design has a better proficiency.

Diagram 3.1.1 The Drawing of the first bridge.

Figure 3.1.2 Bridge after load test.

Figure 3.1.1 Preparing for the first test.

In order to test the proficiency of the bridge, we made the bottom chord into I-beam design due to most of the tension of the bridge is rely on bottom chord. Therefore, by adding I-beam able to enhance the strength and maximum load carry of the bridge. Besides that, we also apply sandwich joint in order to make a few layers for the truss bridge.

ARC 2523 Project 1 Fettuccine Truss Bridge

Diagram 3.1.2 Breakage point of Bridge1, which all located at the bottom chord.

Figure 3.1.3 The truss of Bridge1 detached from bottom chord.

Bridge Weight

81g

Load Carried

1300g

Efficiency

20.86

Figure 3.1.4 The bottom chord of Bridge1 breaks nearby the joint connection.

During the load testing experiment, although the truss did not break but it was detached from the bottom chord at certain amount of load. Besides, I-beam was used as our bottom chord to enhance the efficiency of the bridge but we do not realized that the connection of I-beam also affect the bridge to break down. This is because the breakage of bridge occurred at the bottom chord and also it breaks at the part where we join the fettuccines together. From our observation of this experiment, we believedto that the failure of the bridge occurred 3.2 Bridge Truss Design2 (Chosen Further Improvise) mainly due to our poor workmanship.

ARC 2523 Project 1 Fettuccine Truss Bridge

Diagram 3.1.3 The drawing of second bridge.

Diagram 3.1.4 Top Elevation of the joint.

Figure 3.1.5 Applying the joint in Bridge1.

Figure 3.1.6 Applying the joint in Bridge2.

This is our second design of Waddell â&#x20AC;&#x153;Aâ&#x20AC;? Truss Bridge. In order to test the proficiency of both the first and second design, we used the same method such as using the same dimension to make the bridge, to connect the truss and also I-beam acting as our bottom chord.

ARC 2523 Project 1 Fettuccine Truss Bridge

Figure 3.1.7 The bottom chord of Bridge2 break into half.

Figure 3.1.8 Heavy load caused the i-Beam break.

Bridge Weight

80g

Load Carried

2500g

Efficiency

78.0

During the load testing experiment, the adhesive of the truss was strong and able to holds the bridge from detaching the bottom or/and top chord. However, I-beam as bottom chord of the bridge was broken into half due to the load it carry and also the joint connection of I-beam. From the experiment, we have concluded that with the strong connection from using the adhesive, it helps the truss bridge to carry more load and bottom chords also take major part to withstand the tension of the whole bridge. Hence, the connection of the joint should be carefully taking in consideration during the making process. Throughout both load testing experiments, we have decided to use Bridge Truss Design 2 as because it has better proficiency compare to the first design. Thus, we will be improvising this design by3.3 its Bridge adhesive, joint Design3 connections and orientation of the trusses. Truss

ARC 2523 Project 1 Fettuccine Truss Bridge

3.2 Bridge Truss Design3 This is our third design, an improvised version of Bridge2. In this design, we replaced the previous joint method with double layered fettuccine to strengthen the membersâ&#x20AC;&#x2122; individual tension strength. We also change the top chord to C-beam so that it can withstand more forces. The changes were made as the previous design snapped its top chord completely, thus we assume that the top chord should contain a stronger member. Also we lowered down the height of the fettuccine bridge to 60mm as the truss would endure lesser forces exerted on them.

Diagram 3.2.1 The drawing of the third bridge.

Diagram 3.2.2 Orientation of the member and its connection with the C-beam on top chord.

Figure 3.2.1 Bridge after load test.

ARC 2523 Project 1 Fettuccine Truss Bridge

Diagram 3.2.3 Breakage point of Bridge3.

Figure 3.2.4 The I-Beam on bottom chord break into half.

Figure 3.2.3 The C-Beam on top chord break into parts.

Bridge Weight

98g

Load Carried

4692g

Efficiency

224.64

Due to the joints between members and top chord is not suitable for C-Beam, it did not sustain long and then break. While most of the load goes to I-Beam on bottom chord and caused the bottom cord break into half. From the experiment, we have concluded that fettuccine is stronger when it is vertically facing compared to horizontal facing. This principle applied to fettuccine constructed C-beams as well. The reason this bridge failed is because we place the C-beams at the top chord horizontally, which increase its compression force and canâ&#x20AC;&#x2122;t hold more force than we expected it to be. Eventually this ends up with bottom chord to mainly supporting the whole load, thus it easily breaks before more loads are applied.

ARC 2523 Project 1 Fettuccine Truss Bridge

3.3 Bridge Truss Design4 This is our forth design. By learning what we did wrongly on the third bridge, we changed to I-beams on top chord so that it will enhance its tension strength. We also shrink the length of the top chords and truss members to 350mm so that both the sides will have an extra 50mm span. This is because we realize that way will allow more force to be distribute to the sides of the table, thus the members and chords will have lesser work to do. We also change the direction of the member that are facing outwards to inwards after knowing they will work more efficiently when placed, to enhanced the member strength, we also made it into double layered members.

Diagram 3.3.1 drawing of the third bridge

Figure 3.3.1 I-Beam is used for both truss and bottom chord.

Diagram 3.3.2 Orientation of the member and its connection with Ibeam top chord Figure 3.3.2 picture showing the bridge 24

ARC 2523 Project 1 Fettuccine Truss Bridge

Diagram 3.3.3 Breakage point of Bridge4.

Figure 3.3.3 The members detached from each other due to the i-Beam break. Bridge Weight

102g

Load Carried

6300g

Efficiency

389.11

Figure 3.3.4 The bottom chord break.

During the experiment, the bridge remains as it is when a load of 4000g were applied on it. But when it breach the 4000g mark, it started to deform and bending occurred at the bottom chord. At the end of the experiment, the bottom chord breaks as well as the joint that join truss members and top chord together. From there, we realized that the workmanship needed to be really precise so that the members can be correctly received the force distribution so that when forces will distribute evenly throughout the bottom chord. And special mention to the shrunken length of the top chord and members. This allow the bottom chord to be longer than the top, which makes the extra spaces at the two sides. This we observe that it helps quite a lot in term of helping the bridge to exert forces to the side of the tables. 25

ARC 2523 Project 1 Fettuccine Truss Bridge

3.4 Bridge Truss Design5 In our fifth design, the difference between this design and the previous one is we replaced the top chord with the double layered fettuccine, added bracing to the four members closest to the centre and also added another layer to the bottom chord making it a 3 layered fettuccine I-beam. We also enhanced our workmanship by making it more precise.

Diagram 3.4.1 The drawing of Bridge5.

Figure 3.4.1 Perspective view of Bridge5.

Figure 3.4.2 Layers of Fettuccine stick together to build all the truss members.

Figure 3.4.3 Fettuccine cut in angle.

Figure 3.4.4 Core horizontal members stick inside the i-Beam (Bottom Chord).

ARC 2523 Project 1 Fettuccine Truss Bridge

Figure 3.4.5 The central element in the middle break.

Figure 3.4.6 One of the horizontal element break.

Bridge Weight

81g

Load Carried

8360g

Efficiency

862.83

During the test, the bridge acted quite different compared to the forth design. Rather than the bottom chord started to deform. It was the two ends that expanded out started to stretch themselves at the table. While reaching 6000g mark, the bottom chord, members and top chord are all still in place and didnâ&#x20AC;&#x2122;t deform at all. When it reached the maximum load it could take, only the centre core member snapped and all the other remain in place. Conclusion, we choose this design as our final design. This is because it could withstand a high load and also only the centre member break, which means the force distribution in this design is very even until a point where all our previous problems with breaking of the top chord and bottom chord are solved.

ARC 2523 Project 1 Fettuccine Truss Bridge

4.0 Final Bridge

Diagram 4.0.1 Final Fettuccini Bridge

4.1 Amendments The final bridge design is same as the 7th fettuccini bridge we made previously as itâ&#x20AC;&#x2122;s efficiency is the highest among the bridges we made that withstand 11 Kg. However, the previous bridge we can make can only withstand 7.3Kg. We are using the same dimension for the final bridge but different enhancement on particular members, which do not carry much weight to control the total weight of the bridge to meet the requirement.

ARC 2523 Project 1 Fettuccine Truss Bridge

4.2 Top & Bottom Chord Fettuccini is weak in compression but good in tension. Therefore, several layers are added to enhance the ability to withstand compression force. After comparing the 6 th (I-Beam as the top main diagonal members and the horizontal member) and 7th (I-Beam as the horizontal member only), we found out that the main supporting members that withstand the highest weight among others members is only the longest horizontal span which have direct contact with the ground surface.

I-Beam Without I-Beam

Figure 4.2.1 I-beam as the top chord member

Figure 4.2.3 Two layers of fettuccini as top chord member

Therefore, amendments are made, where we remove the I-Beam for the top main diagonal member to reduce the weight of the whole bridge. After several tests on the design of Ibeams, we concluded that those I-Beams that consists of two layers of fettuccini horizontally and vertically (further explanation in later paragraph) are the strongest among others.

ARC 2523 Project 1 Fettuccine Truss Bridge

4.3 Core Horizontal Element

Figure 4 3.1 I-Beams on both side of the strut

Figure 4.3.2 I-beam made up by 4 layers of fettuccini (middle) between 2 one-layer fettuccini (top and bottom).

Cross I-beams

Figure 4.3.3 Cross arrangement of core member

Diagram 4.3.1 close up look of the core members

The Core horizontal element is amended into cross arrangement as it provide more stiffness for the load to fix in its direction. The upper two pieces of fettuccini is added so that the core form a triangle to fit the S hook accurately.

ARC 2523 Project 1 Fettuccine Truss Bridge

4.4 Vertical & Diagonal Truss

Figure 4.4.2 After design of the truss

Figure 4.4.1 Previous design of the truss

Diagram 4.4.1 Compression force in the previous truss design

Diagram 4.4.2 Tension force in the after truss design

Amendments are made in the trusses as well. Adding more diagonal force in opposing direction help in increasing tensile strength after the calculation. These members are fewer layers than the main horizontal spans as they act as aiding members.

ARC 2523 Project 1 Fettuccine Truss Bridge

4.5 Joints

Diagram 4.5.2 Base trusses that sit between the bottom chords

Diagram 4.5.1 Roof truss that sit on the top chord

For the top chord and bottom chord, amendments are made. For top chord, the fettuccini layers are reduced to one piece as it does not carry much force. For the bottom chord, the position of putting it between the two I-beams enhance the direct distribution of compression force. Rather than putting it on top of the two I-beams, they are joined in between.

Figure 4.5.1 Previous join which do not cut in angle

Figure 4.5.2 Current joint with accurate angle

For the joint in vertical and diagonal truss, fettuccini is cut into angle that fix securely on each other. This is to prevent unnecessary force such as shear force from happening and thus enhance the distribution of force.

ARC 2523 Project 1 Fettuccine Truss Bridge

4.6 Members and Connection of Fettuccini Bridge

Diagram 4.6.1 Bottom part of the bridge joint

Diagram 4.6.2 Upper part and middle part of the bridge joint

6 layers of Fettuccini 5 layers of Fettuccini 2 layers of Fettuccini

ARC 2523 Project 1 Fettuccine Truss Bridge

4.7 Joint Analysis Bottom Chord

Diagram 4.7.1 Bottom Chord of the bridge

The bottom chord of the bridge used the I-beam design after experienced the failure of using the C-Beam connection. The I-Beam is formed by two layers of vertical member in between two layers of horizontal layers of each side. The requirement length of the clear span is 35cm.

The extension joint

Due to the limited length of available fettuccini, which is 20-25cm; extension of the fettuccini is required. However, the extensions need to be carefully planned to avoid the overlapping of extension joint.

Diagram 4.7.2 Exploded drawings of fettuccini extension joint

The beam is arranged in the longer span in the middle with shorter span both side while another layer with both side almost equal lengths. This is to avoid overlapping of extension joint which will strongly affect the strength of the span. The horizontal element of the beam works in the same way. The total length of the horizontal span is originally 40cm with 2.5 cm each side that sit on the table. We modify the total length of the span is 45cm with 7.5 cm on each side to enhance the tensile strength.

ARC 2523 Project 1 Fettuccine Truss Bridge

Top Chord

Diagram 4.7.3 Top Chord of the bridge

The top chord is cut into angle to fit into another top chord to form a prefect triangle. Two layers of fettuccini overlaying each other make up this top chord rather than I-Beam as it increase the weight of the bridge. It is due to the aid of the vertical acting as tension force to reduce the burden of top chord which suffering compression force.

Figure 4.7.1 Top chord joint supported by strut

The Strut is stick beneath the top chord to act as support rather than locating in the middle of the top chords. This is to ensure compression force (Top chord) is evenly distributed to the other vertical and diagonal members. Diagram 4.7.4 Strut as supporting member beneath the top chord

ARC 2523 Project 1 Fettuccine Truss Bridge

Vertical and Diagonal Truss

Diagram 4.7.5 Vertical and Diagonal Truss

Diagram 4.7.6 Tension distributions in the diagonal member (Cross Bra0cing)

The vertical and diagonal truss is crucial in distributing the force asserted by the load. The vertical and diagonal truss withstands more tensile strength in the middle part where the load being located. The diagonal truss in the middle part is in different direction of the other diagonal truss direction. It was done purposely to provide tension strength at particular member.

The cross bracing include one long truss (blue) which act in different direction with another two shorter truss (red) for the same direction member. This is to ensure securely strong truss to withstand force, preventing from breaking so easily.

Figure 4.7.2 The formation of cross-bracing.

ARC 2523 Project 1 Fettuccine Truss Bridge

Diagram 4.7.7 The joint of vertical and diagonal member between the top and bottom chord

Diagram 4.7.8 Close up look of the vertical and diagonal member

The vertical and diagonal trusses are located in between the top chord and the bottom chord rather than surrounding the chord. This is to ensure direct force distribution of force throughout the other members. Tests are done with vertical and horizontal element being put surrounding the chord, the weight carried is lower.

ARC 2523 Project 1 Fettuccine Truss Bridge

Core Horizontal Member

Diagram 4.7.9 The core horizontal member of fettuccini bridge

The Core horizontal member must be as strong as possible because it is the load is directly asserted on it. The core element must have great tension force to overcome the direct compression force from the load. Therefore, I-beam design is applied. The overlapping of two Ibeams on each other provide 4 times stronger than without crossing. The core elements sit on the bottom chord as it direct transfer the load to the nearest and strongest member (Bottom Chord).

Figure 4.7.4 Front elevation of crossing of Ibeam like core horizontal member

Figure 4.7.5 Side elevation of crossing of I-beam like core horizontal member

Diagram 4.7.9 2 extra piece of fettuccini on top of the core

ARC 2523 Project 1 Fettuccine Truss Bridge

Horizontal Truss

Diagram 4.7.10 Upper and Lower Truss

The horizontal trusses are inserted to prevent torsion force in the bridge when load is applied. The force rarely distribute in between these members, therefore, only one layer of fettuccini is required. However, those who are nearer to the core element where the load located and at the end of the bridge are 2 layers.

Figure 4.7.6 The cross bracing in upper truss

ARC 2523 Project 1 Fettuccine Truss Bridge

4.8 FINAL MODEL MAKING Firstly, an accurate Autocad drawing of the bridge is printed out as the guide for the bridge construction. Then, two I-beams are constructed as the base of the bridge

Diagram 4.8.1 The arrangement of fettuccine in I-beam construction.

Diagram 4.8.2 The connection of Fettuccine inside IBeam.

Figure 4.8.1 Close up picture showing the construction of I-beam with Fettucine.

ARC 2523 Project 1 Fettuccine Truss Bridge Secondly, the outline of triangle is constructed.

Diagram 4.8.3 The second step of erection, the outline of the triangle.

Diagram 4.8.4 The connection between the triangle and I-beam.

Diagram 4.8.5 The construction and the connection of the triangle.

ARC 2523 Project 1 Fettuccine Truss Bridge Thirdly, the vertical members are constructed. These member are purposely constructed to support the whole structure and resist the compression and tension force.

Diagram 4.8.6 Third step of erection, the vertical members.

Diagonals are added after that to resist part of the tension and compression forces and avoid shear forces.

Diagram 4.8.7 Forth step of erection, the diagonal members.

ARC 2523 Project 1 Fettuccine Truss Bridge A pair of diagonal members are constructed at mid point at the fifth step to resist compression force. These members efficiently balanced the forces created.

Diagram 4.8.7 Fifth step of erection, the middle diagonal members.

Figure 4.8.1 Close up picture of the connection of the middle diagonal members.

Lastly, a series of members having 60mm in length are served to connect the bottom and the top chords of two main facades. The members of the bottom stuck into I-beam and those on the top rest well on the top chords at the same position with the vertical members. Diagonals are constructed on the top to strengthen the connection. These members are served to resist torsion forces.

Diagram 4.8.8 The connection of two main facades.

Figure 4.8.2 Close up picture of the core element.

ARC 2523 Project 1 Fettuccine Truss Bridge

Diagram 4.8.10 the diagonal members on the top.

Diagram 4.8.9 The construction of horizontal members on the top.

Diagram 4.8.11 Bottom view.

Diagram 4.8.12 Top view.

Diagram 4.8.13 Elevation drawing of the bridge.

ARC 2523 Project 1 Fettuccine Truss Bridge

4.9 Final Bridge Test & Load Distribution Compression Tension

Diagram 4.9.1 The load distribution of tension and compression force (internal)

Bridge weight: 79g Load Carried: 15.5kg Efficiency: 3041

During the final bridge test, our bridge can withstand 15.5 kg and reach efficiency of 3041, which is about 4 times compare to the 7th bridge we made. This is due to the presence of more tension force than compression force especially the part where load being located. Tension force is used to resist the compression force of the load. The middle part of the bridge encounters a lot of tension force that is good in preventing the bridge from breaking. The compression force of the upper part is evenly distributed among the vertical and diagonal truss. Some of the vertical and diagonal members also help in tension force. The tension force in this final bridge is more than the compression force comparing to previous design. Thatâ&#x20AC;&#x2122;s why the efficiency is far away beyond our expectation, which can carry about 15.5 Kg. The bridge is not left to dry that long until become fragile. Therefore, enhancing the stiffness of the bridge. The bridge breaks in the core horizontal element only, and it bounces off after broke. The other member do not break either, this showed the force among the members is in equilibrium.

Figure 4 .9.1 Final bridge test (before break)

Figure 4.9.2 Final bridge test (after break)

ARC 2523 Project 1 Fettuccine Truss Bridge

4.10 Calculation of Distribution of Forces for Final Bridge

ARC 2523 Project 1 Fettuccine Truss Bridge

CHAPTER 5: Reference Patent US529220 - Truss-bridge.(1894, November 13). Retrieved Oct 1, 2015, from http://www.google.com/patents/US529220

Ching, Francis D.K (2008) Building Construction Illustrated Fourth Edition. New Jersey: John Wiley & Sons, Inc.

Lamb, Robert, and Michael Morrissey. "How Bridges Work" (01 April 2000). Retrieved Oct 1, 2015, from http://science.howstuffworks.com/engineering/civil/bridge.html

ARC 2523 Project 1 Fettuccine Truss Bridge

CHAPTER 6: INDIVIDUAL CASE STUDIES 6.1 Case Study 1 (Chan Pin Qi)

ARC 2523 Project 1 Fettuccine Truss Bridge

6.2 Case Study 2 (Lim Yee Qun)

ARC 2523 Project 1 Fettuccine Truss Bridge

6.3 Case Study 3 (Te Li Theng)

ARC 2523 Project 1 Fettuccine Truss Bridge

6.4 Case Study 4 (Liew Qiao Li)

ARC 2523 Project 1 Fettuccine Truss Bridge

6.5 Case Study 5 (Woo Wen Jian)

ARC 2523 Project 1 Fettuccine Truss Bridge