building structure: project 1
TRANSCRIPT
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!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!Building!Structures!(ARC!2523)!
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MEMBERS&:&&
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NUR&BAHIRAH&BINTI&ABDUL&RAHMAN&&&&&&&&&&0311085&
NUR&NATASYA&LIYANA&BINTI&ZULKHAIRI&&&&&&&0320851&
NUR&AIMAN&BINTI&MOHAMAD&SHAKIR&&&&&&&&&0311759&
EINAS&ADEL&AHMED&MAIZRAN&&&&&&&&&&&&&&&&&&&&&&&&0316350&
MOHD&SHAHRUL&IZZAT&BIN&ABDULLAH&&&&&&&&&0317185&
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CONTENTS!
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1.0 INTRODUCTION!• 1.1&OBJECTIVES&• 1.2&LEARNING&OUTCOMES&
&2.0 METHODOLGY!
• 2.1&PRECEDENT&STUDY&• 2.2&MATERIALS&TESTING&AND&EQUIPMENT&PREPARATION&• 2.3&MODEL&MAKING&AND&DESIGN&DEVELOPMENT&• 2.4&STRUCTURAL&ANALYSIS&• 2.5&BRIDGE’S&EFFICIENCY&CALCULATION&
&3.0 PRECEDENT!STUDY!
• 3.1&PORT&KLANG&BRIDGE!• 3.2&ANALYSIS!
!4.0 MATERIALS!ANALYSIS!AND!EQUIPMENTS!
• 4.1&MATERIALS&• 4.2&EQUIPMENTS&
&5.0 MODEL!MAKING!AND!DESIGN!DEVELOPMENT!
• 5.1&MODEL&MAKING&• 5.2&DESIGN&DEVELOPMENT&
!6.0 BRIDGE!TESTING!AND!ANALYSIS!!
• 6.1&BRIDGE&1&• 6.2&BRIDGE&2&• 6.3&BRIDGE&3&• 6.4&BRIDGE4&• 6.5&&COMPARISON&OF&JOINTING&METHOD&
&&7.0 FINAL!DESIGN!
!8.0 CONCLUSION!!
9.0!CASE!STUDY!
10.0!REFERENCES!
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& 3&
1.0!INTRODUCTION!
The&aim&of&this&project&ia&to&successfully&design&an&effective&truss&bridge&through&the&analysis&conducted&on&precedent&studies,&as&well&as&the&crits&and&advices&from&the&tutor.&The&material&used&to&represent&the&trusses&is&fettuCcine.&
Truss&is&a&main&structure&of&the&bridge&that&built&up&of&three&or&more&members&which&are&normally&considered&being&pinned&and&hinged&at&the&joint.&There&are&many&types&of&trusses&such&as&Pratt,&Howe,&Warren&and&Bowstring.&Load&applied&to&the&truss&is&transmitted&to&joint&so&that&each&individual&member&are&in&either&pure&tension&or&compression.&
1.1!OBJECTIVES!
The&objectives&of&this&project&are:&
• To&develop&student’s&understanding&of&tension&and&compressive&strength&of&construction&materials.&
• To&develop&student’s&understanding&of&force&distribution&in&a&truss.&• To&design&a&perfect&truss&bridge&which&fulfills&the&following&criteria:&&
o High&level&of&aesthetic&value&o Minimal&construction&material&
1.2!LEARNING!OUTCOMES!
• Able&to&evaluate,&explore&and&improve&attributes&of&construction&materials.&• Explore&and&apply&understanding&of&load&distribution&in&a&truss.&• Able&to&evaluate&and&identify&tension&and&compression&members&in&a&truss&structure&• Explore&different&arrangement&of&members&in&a&truss&structure&
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2.0!METHODOLOGY!
2.1!PRECEDENT!STUDY!
The&precedent&study&had&been&conducted&to&research&for&a&truss&bridge&and&study&on&its&joints,&arrangement&of&members&and&orientation&of&each&member&and&helped&us&to&identify&the&tension&and&compression&members.&It&also&helped&us&to&develop&an&understanding&of&the&connections&members&and&how&load&is&transferred.&Then,&the&Fettuccine&Bridge&was&designed&and&constructed&based&on&the&information&that&we&gained&from&the&precedent&study.&
2.2!MATERIALS!TESTING!AND!EQUIPMENT!PREPARATION!
In&order&to&build&the&strong&fettucine&bridge,&we&explored&the&different&types&and&brands&of&materials&such&as&glues&and&fettuccine&that&can&provide&maximum&strength&and&efficiency&to&the&bridge.&The&equipment&were&prepared&to&build&the&bridge.&
2.3!MODEL!MAKING!AND!DESIGN!DEVELOPMENT!
A&discussion&had&been&made&by&the&group&members&to&choose&the&best&truss&for&our&fettuccine&bridge.&The&idea&had&been&sketched&and&designed&using&AutoCAD&software&and&is&printed&out&to&scale&for&model&making&process.&&
There&are&some&requirements&of&Fettuccine&Bridge&that&must&be&followed:&
a) 750mm&clear&span&bridge&b) Maximum&weight&of&200g&c) The&bridge&will&be&tested&to&fail&
The&test&need&to&be&done&for&several×&to&identify&the&strength&and&the&weakness&of&the&Fettuccine&Bridge.&
2.4!STRUCTURAL!ANALYSIS!
The&structural&analysis&is&done&to&determine&the&effects&of&load&on&the&Fettuccine&Bridge&and&the&bridge’s&members&by&calculation&
2.5!BRIDGE’S!EFFICIENCY!CALCULATION!
The&efficiency&of&the&bridge&is&calculated&after&it&is&tested&to&fail,&using&the&efficiency&formula:&
( )bridge of WeightLoad MaximumE,Efficiency
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3.0!PRECEDENT!STUDY!
3.1!PORT!KLANG!BRIDGE!
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Port&Klang&Bridge&is&a&reinforced&steel&truss&girder&bridge,&and&it&was&the&first&double&decked&bridge&built&in&Malaysia.&The&bridge&was&constructed&between&1958&and&1960.&In&the&1990’s,&due&to&the&high&capacity&traffic&with&the&upgrading&of&the&Federal&Highway&Route&2&(Klang&–Kuala&Lumpur)&into&six&lane&carriageway&toll&highway&from&1991&to&1993.&
The&double&decked&bridge&was&closed&to&traffic&and&the&new&concrete&bridge&with&six&lane&carriageway&was&built&beside&the&original&double&decked&bridge.&The&bottom&deck&is&a&pedestrian&walkway&bridge&while&the&top&deck&is&a&motor&vehicle&bridge.&However&in&the&year&1990s,&the&top&deck&of&the&bridge&was&renovated&into&bridge&square&called&Dataran&Jambatan&Kota.&
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3.2!ANALYSIS!
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4.0!MATERIALS!ANALYSIS!AND!EQUIPMENTS!
4.1!MATERIALS!
4.1.1&FETTUCCINE&
Fettuccine&is&the&main&materials&for&the&bridge.&Two&types&of&fettuccine&with&different&brand&had&been&tested&to&find&the&best&material&to&be&used&for&the&Fettuccine&Bridge.&
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Number&of&fettuccine&used& Weight&Sustained/ml&(San&Remo)&
Weight&Sustained/ml&(Kimball)&
1& 200& 210&2& 300& 350&3& 420& 480&4& 530& 600&
*100ml&=&100g&
Based&on&analysis&and&comparison&between&both&brands,&the&San&Remo’s&fettuccine&is&more&suitable&to&use&compared&to&Kimball’s&fettuccine.&
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Fettuccine&Brand& San&Remo& Kimball&Characteristic& • Thick&
• Strong&• Hard&to&bend&• Flat&surface&
• Thin&• Easy&to&bend&• Rounded&surface&
Efficiency&Ranking& 1& 2&
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4.1.2&GLUE&(ADHESIVE&MATERIAL)&
Several&types&of&glues&had&been&used&to&find&the&best&glue&to&be&used&for&the&Fettuccine&Bridge.&The&selection&of&glue&is&important&to&ensure&the&fettuccine&stick&well&to&each&other&and¬&to&break&easily.&
Type&of&Glue& Properties& Efficiency&Ranking&Dolphin&Super&Glue&(Brush&On)&
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• High&efficiency&• Fastest&solidify&time&• Lighter&in&weight&• Comprehensive&• Easily&to&use&(with&
brush)&
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Dolphin&Super&Glue&
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• High&Efficiency&• Faster&solidify&time&• Lighter&in&weight&
2&
Alteco&110&Super&Glue&
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• High&efficiency&• Slower&solidify&time&• Lighter&in&weight&&
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UHU&multipurpose&glue&
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• Low&efficiency&• Slowest&solidify&time&• Heavier&in&weight&
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4.2!EQUIPMENTS!
4.2.1&ShHOOK&
ShHook&is&used&to&hang&the&load&to&the&Fettuccine&Bridge.&So,&all&the&forces&are&applied&on&one&point&of&the&bridge.&
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4.2.2&WATER&BOTTLES&AND&PLASTIC&
Water&bottles&filled&with&water&act&as&the&load&to&test&the&strength&of&the&Fettuccine&Bridge.&The&plastic&will&be&hung&to&the&ShHook&before&it&filled&with&bottles.&The&bottles&will&be&weighed&using&weighing&machine&after&the&bridge&is&broke&apart.&
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4.2.3&WEIGHING&MACHINE&
It&can&be&used&to&weigh&the&mass&of&Fettuccine&Bridge&to&make&sure&it&will¬&exceed&200g&of&maximum&weight.&The&weighing&machine&also&can&be&used&to&weigh&the&bottles&that&been&used&as&load.&&
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4.2.4&CAMERA&
Camera&is&used&to&record&the&making&process&and&take&photos&for&documentation&as&the&evidences.&&
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5.0!MODEL!MAKING!AND!DESIGN!DEVELOPMENT!
5.1!MODEL!MAKING!
5.1.1&GANTT&CHART&
& WEEK&&1&
WEEK&&2&
WEEK&&3&
WEEK&&4&
WEEK&&5&
WEEK&&6&
WEEK&&7&
Idea&and&design&development&process.&
• Discussion&about&the&bridge&trusses.&
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Testing&the&strength&of&Fettuccine&and&deciding&the&best&materials&to&be&used.&
• Suitable&adhesive&material.&
• Suitable&fettuccine&brand.&
• Method&of&joint.&
& & & & & & & &
Making&and&testing&the&first&bridge.&
• Find&out&the&main&problem.&
• Deciding&the&arrangement&of&the&bridge&members.&
• Deciding&the&best&bridge&truss&to&be&used.&
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Making&and&testing&more&bridges&to&solve&the&problems.&
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Making&and&testing&the&final&bridge.&
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Preparing&the&report&and&submission.&
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5.1.2&METHOD&OF&CONSTRUCTION&
STEPS& DESCRIPTIONS&Step&1& The&bridge&truss&design&is&drawn&using&AutoCAD&software&and&printed&in&1:1&
scale.&It&helps&us&to&measure&the&members’&dimensions&and&to&cut&them&accurately.&
Step&2& The&fettuccines&are&cut&carefully&and&precisely&based&on&the&printed&drawing.&This&is&because&any&of&the&damages&will&reduce&the&strength&of&the&bridge.&Then,&several&layers&of&fettuccine&are&glued&to&provide&strength&of&the&members.&
Step&3& The&fettuccines&are&glued&with&the&other&members&using&adhesive&material&like&glue.&Some&precautions&must&be&considered&such&as:&&
• The&glues&must&be&applied&at&the&surface&evenly.&&• There&is&no&empty&space&between&the&sticking&parts.&• The&members&are¬&slanted&
Step&4& Step&1&to&3&is&repeated&to&build&the&other&truss&of&the&bridge.&Step&5& The&horizontal&members&are&cut&to&build&a&base&which&can&connect&both&
trusses.&Then,&several&layers&of&fettuccine&are&glued&to&provide&strength&of&the&members.&&
Step&6& The&horizontal&members&are&glued&to&hold&the&trusses.&Some&precautions&must&be&considered&such&as:&
• The&glues&must&be&applied&at&the&surface&evenly.&&• There&is&no&empty&space&between&the&sticking&parts.&
Step&7& The&bridge&is&completed&and&the&finishing&job&will&be&done.&&Step&8& The&bridge&is&weighed&on&weigh&machine&to&check&if&the&bridge&is&exceeded&the&
required&weight&and&to&be&recorded&for&the&calculation&process.&Step&9& The&bridge&is&ready&to&be&tested&and&the&results&are&recorded&and&calculated&
for&the&report.&&
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5.2!DESIGN!DEVELOPMENT!
5.2.1&WARREN&TRUSS&
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In&this&project,&we&decided&to&use&Warren&truss&design&as&it&worked&perfectly&in&our&model&testing.&The&Warren&truss&design&is&widely&used&due&to&its&high&efficiency.&We&did&some&improvement&to&the&design&to&enhance&the&efficiency&of&the&bridge.&&
In&order&to&increase&the&strength&of&the&bridge,&the&fettuccines&are&layered&to&make&it&stronger.&Several&tests&had&been&conducted&using&1,&2,&3&and&4&layers&of&fettuccines.&The&result&can&be&seen&at&material&analysis§ion.&It&is&proven&that,&the&thicker&the&fettuccines&layer,&the&stronger&it&is.&However,&we&must&consider&the&weight&as&it&will&also&increase.&
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5.2.2&JOINTS&
Joint&is&the&main&concern&in&order&to&ensure&the&strength&of&the&whole&bridge.&The&failure&to&join&the&fettuccine&carefully&and&precisely&will&cause&the&whole&bridge&to&break.&&
5.2.2.1&STACKING&METHOD&
For&the&top&part,&the&2&layer&fettuccines&sticks&are&stick&edge&to&edge.&However,&this&method&is¬&strong&enough&to&secure&the&top.&Hence,&2&pieces&of&fettuccine&is&glued&at&both&side&of&the&connected&stick&to&secure&the&joint&of&it.&This&method&is&used&to&reduce&the&breaking&point&of&the&bridge.&
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5.2.2.1&SLOTTING&METHOD&
Horizontal&members&are&slotted&into&the&beam&the&bridge&structure.&
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5.2.2.3&MITER&BUTT& METHOD&
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This&joint&is&used&to&connect&the&diagonal&members&to&the&horizontal&members.&This&join&required&an&accurate&angle&to&ensure&the&members&are&stick&to&each&other&evenly.&
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5.2.2.4&PLAIN&BUTT&METHOD&
This&joint&is&used&to&connect&the&vertical&members&to&the&horizontal&member.&This&join&is&commonly&used&as&it&is&easier&compared&to&other&joint.&However,&this&joint&is¬&strong&enough&compared&to&others&&
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6.0!BRIDGE!TESTING!AND!ANALYSIS!
6.1!BRIDGE!1!
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! !
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For&the&first&bridge&testing,&we&decided&to&use&a&simple&warren&truss&design.&We&tested&using&a& shorter& clear& span& and& total& length& to& test& the& bridge.& As& for& the& vertical& and& diagonal&members,&the&wider&surface&of&the&fettuccine&was&arranged&to&face&the&front&façade.&While&the&top&and&bottom&beams&are&using&Ihbeam&design.&&
Clear&span&=&400mm& & & & Total&Length&=&500mm&
Weight&of&bridge&=&0.131&kg& & & Height:&60mm&
Total&Load&Withstand&=&6&kg& & & Efficiency&=&&&(max%load)2%&&&%%%&%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% % % % % % %%%%%%weight%of%bridge%
&&&&&&&&&&&&&&& & & & & &&&&&&&&&&&&&&&&&&=&(6)2&
&&&&&&&&& &&&&&& & & & & & &&&&&&&0.131&
&&&&&&&&&&&&&&&&& & & & & & &&&=&274.8&
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BREAKING!POINT!:!&
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PROBLEM!IDENTIFICATION:!
1)&The&clear&span&of&the&bridge&is&less&than&the&requirement,&which&is&750mm.&
2)&The&bridge&broke&due&to&the&false&orientation&and&arrangement&of&the&members.&
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SOLUTIONS:!
1)&Change&the&orientation&of&the&vertical&members&of&the&fettuccine.&
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2)&The&arrangement&of&the&members&in&the&IhBeam&is&changed&from&horizontal&to&vertical.&
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BREAKING&POINT&
LOAD&HANGING&POINT&
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6.2!BRIDGE!2!
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
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!!!!!!!!!!!!!!!!!!!!!!! !
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The&second&bridge&testing&is&using&a&different&truss&design&to&compare&the&efficiency&of&this&design& and& the& first& one.& We& tested& using& the& same& clear& span& and& total& length.& The&maximum&height&is&doubled.&All&members&including&the&vertical,&horizontal&and&upper&chord&members& are& using& three& layers& of& fettuccine.& The& bottom&beam& is& using& the& improved& Ihbeam&design.&&
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Clear&span&=&400mm& & & & Total&Length&=&500mm&
Weight&of&bridge&=&0.179&kg& & & Height:&120mm&
Total&Load&Withstand&=&3.2&kg& & & Efficiency&=&&&(max%load)2%&&&%%%&%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% % % % % % %%%%%%weight%of%bridge%
&&&&&&&&&&&&&&& & & & & &&&&&&&&&&&&&&&&&&=&(3.2)2&
&&&&&&&&& &&&&&& & & & & & &&&&&&&0.179&
&&&&&&&&&&&&&&&&& & & & & & &&&=&57.2&
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BREAKING!POINT!:!!
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PROBLEM!IDENTIFICATION:!
1)&The&design&of&the&truss&is¬&weaker&than&the&first&one.&
2)&There&is&no&upper&beam&in&the&design&but&instead&it&uses&upper&chords,&which&are&weaker&in&terms&of&load&distribution.&
3)&The&design&of&the&upper&chords&is&much&thinner&than&the&design&of&the&previous&beam.&
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SOLUTIONS:!
1)&The&first&truss&design&is&a&stronger&design&for&load&distribution.&Therefore,&for&the&next&test&we&are&testing&the&first&design&while&improvising&it.&
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The%I6Beam%(left)%is%stronger%than%the%chord%(right)%design.!
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BREAKING&POINT&
LOAD&HANGING&POINT&
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6.3!BRIDGE!TEST!3&&&&&&&&&&&&&&&&&&&!
&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&& !
!!!!!!!!!!!!!!!!!!!! !
For&the&third&test,&we&used&the&actual&bridge&length&based&on&the&requirement.&The&height&of&this&warren&truss&bridge&design&was&changed&with&additional&diagonal&truss&members.&The&upper&and&lower&chord&layers&are&increased&to&7&layers&each,&as&these&chord&members&are&the&most&critical&aspect&in&the&bridge&design.&&
Clear&span&=&&&750&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&Total&length=&850&&&&&&
Weight&of&bridge&=&260g&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&Efficiency&=&(max&load)&2&&&
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Total&Load&Withstand&=&3.5kg&
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LOAD&HANGING&POINT&
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260&&&&&&&&&&&&&&&&=&47.12&
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!!!!!!!!!!!!!!!!!!!!!!!
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!!!!!!!!!!!!!!!!!!!!!!!!
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
PROBLEM!IDENTIFIED:!!!
h&Weight&of&the&bridge&exceeds&200g&&
h&The&middle&joint&supporting&the&load&(on&the&base)&is&the&weakest&as&it’s&the&only&part&which&breaks.&
SOLUTION:!
h&&Reduce&the&number&of&vertical&members&&
h&Apply&cross&bracing&directly&under&the&middle&of&the&bridge&beam&
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BREAKING&POINT&
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6.4!BRIDGE!TEST!4:&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&& & & &
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The&efficiency&of&design&4&improved&after&the&application&of&cross&bracing&under&the&middle&joint&of&the&bridge&to&sustain&the&load&and&overall&weight&of&the&bridge&decreased&&
Total&length&=&850mm&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&Clear&span&=&750mm&
Weight&of&bridge&=&260&g&&&&&&&&&&&&&&&&&&&&&&&&&Height&=&60mm&
Total&Load&Withstand&=&3.5kg&&&&&&&&&&&&&&&Efficiency&=&&(max&load)2&&&
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CRITICAL&POINT&
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PROBLEM!IDENTIFICATION:!
hThe&middle&connecting&member&to&the&lower&cord&is&the&breaking&point&&
h&Weight&exceeds&200g&&
SOLUTION:!
h&Distribute&the&hanging&load&at&the&middle&by&applying&cross&bracing&throughout&the&entire&base&
h&Reduce&number&of&layers&from&the&upper&chord&
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6.5!COMPARISON!OF!JOINTING!METHODS!
A! B!!!
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!!!!!!!!!!!!! !!!
!Method!A:!The&base&part&is&stacked&on&the&beam.&The&load&is&transferred&to&the&diagonal&member&of&the&truss&instead&of&the&beam.&
!Method!B:!The&base&part&is&slot&into&the&beam.&The&load&is&transferred&directly&to&the&beam&through&the&use&of&the&diagonal&bracing&of&the&base.&!
!Result:!Can&sustain&<&1.5&kg&
!Result:!Can&sustain&>&1.5&kg&!
!Conclusion:!Not&as&effective&as&method&B.&!!
!Conclusion:!Proceed&with&this&method.&
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7.0!FINAL!DESIGN!
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Total&length&=&850mm&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&Clear&span&=&750mm&
Weight&of&bridge&=&200g&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&Height&=&50mm&
Total&Load&Withstand&=&2.1kg&&&&&&&&&&&&&&&&&&&&&&Efficiency&=&&(max&load)2&&&
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Changes&made&for&final&bridge:&&
1.) In&order&to&ensure&the&weight&of&the&bridge&doesn’t&exceed&200g&reduction&of&the&number&of&layers&were&made&on&the&upper&beam&from&7&layers&to&4&layers.&&
2.) Increased&the&spacing&between&the&diagonal&members,&and&reducing&the&height&of&the&vertical&from&6cm&to&5cm.&&
3.) Applied&cross&bracing&throughout&the&entire&base&of&the&bridge,&&4.) Instead&of&sticking&the&joining&members&on&the&top&of&the&lower&beam,&used&the&method&of&
slotting&in&&
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&&&&&&&&&weight&of&bridge&
200&
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Conclusion:&
From&the&result&observed&from&the&final&testing,&the&bridge&achieved&the&efficiency&of&22&only&which&is&quite&low&compared&to&the&other&design&testing&carried&out&previously.&The&weakness&of&the&final&design&happens&due&to:&
&Firstly,&the&reduction&of&the&number&of&layers&on&the&upper&chord&(which&are&the&members&in&compression)&because&it&cannot&sustain&the&load&transferred&to&it&by&the&diagonal&and&vertical&members.&&Secondly,&the&middle&member&of&the&base&where&the&load&hangs&is&inserted&in&between&the&beam&instead&of&placing&it&on&top.&This&creates&more&pressure&on&the&member&itself&instead&of&transferring&the&load&onto&the&entire&structure.&To&conclude,&the&upper&and&lower&beam&should&be&of&the&same&thickness&as&
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Presentation&day&and&Final&Model.&
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BREAKING&POINT&
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8.0!CONCLUSION!
&&&&&&&&&&Having&Klang&Bridge&as&our&precedent&study,&we&had&constructed&total&of&5&fettuccine&bridges&in&order&to&test&and&experiment&on&its&efficiency&in&withstanding&loads.&Klang&Bridge&uses&Warren&Truss&in&its&truss&arrangement.&The&reasons&we&chose&Warren&Truss&is&because&it&is&one&of&the&simplest&yet&strong&designs&compared&to&others.&Warren&Truss&has&equilateral&triangles,&which&minimize&the&forces&to&only&compression&and&tension,&thus&distributes&the&loads& equally.& To& our& astonishment,& when& load& is& applied& to& the& bridge,& sometimes& the&forces&of&the&components&switch&from&compression&to&tension,&especially&those&near&to&the¢er&of&the&bridge,&to&increase&its&efficiency&in&load&distribution.&&
&&&&&&&&&&&&We&achieved&the&highest&efficiency&in&our&third&and&fourth&model&testing,&which&has&the& correct& clear& span& length& as& required& in& the& project& brief.& The& fettuccine& bridges&achieved&an&efficiency&of&47%,&withstanding&a&total&load&of&3.5&kg&and&its&weight&is&only&260&g.& Through& this& project,& we& learned& a& lot& about& the& load& distribution& in& a& structure& and&learned&how&to&calculate&the&type&of&force&applying&in&the&structure&members.&Therefore,&it&is&very& important& for&us& to&understand&how&each&member&works& together&as&a&whole& in&a&structural&system&to&achieve&higher&efficiency&to&carry&out&greater&loads.&&
&&&&&&&&&&&&There& are& a& few& other& factors,& which& can& effect& the& construction& of& the& fettuccine&bridge&such&as&the&type&of&glue,&the&type&of&fettuccine,&and&the&interval&time&between&model&making&and&testing.&The&type&of&glue&and&fettuccine&plays&a&big&role&in&ensuring&the&firmness&of&the&structure.&Furthermore,&we&have&concluded&that&the&faster&the&testing&of&the&bridge&after&doing&the&model&making,&the&longer&the&time&it&can&withstand&the&load.&
& One&of&the&methods&we&used&to&ensure&that&the&bridge&is&measured&and&constructed&in& highest& accuracy& is& by& generating& the& Autocad& drawing& and& print& it& out& to& use& as& our&reference& during& the& model& making& stage.& We& also& tried& to& achieve& the& highest&workmanship& by& working& on& the& bridge& carefully& and& steadily.& Other& than&model&making&stage,&we&realized&that&it&is&important&to&have&proper&planning&in&terms&of&work&delegation&and&time&management.&&
& In&a&nutshell,& this&project&taught&us&to&how&strong&a&structure&can&be& if& its&properly&designed& and& constructed.& In& the& future,& we& as& designers& and& builders,& need& to& think&critically& and& pay& attention& to& detail& so& that& a& structure& can& function& efficiently& without&failure&for&the&safety&of&the&people.&&
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9.0!CASE!STUDY!
Exercise : Truss analysis
Following are 6 different truss systems which carry exactly the same loads. Each group member analyses one of the following case. Determine which truss arrangement is the most effective and explain why.
(Note : Please write your name on your calculation sheets. Omit case 6 if your group has only 5 members).
Case 1
Case 2
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Case 3
Case 4
Case 5.
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10.0!REFERENCES
Boon,&G.&(2011,&January&4).&Warren%Truss.&Retrieved&May&6,&2015,&from&Garrets&Bridges:&
http://www.garrettsbridges.com/design/warrenhtruss/&
Ching,&F.&D.&(2008).&Building&Construction&Illustrated&Fourth&Edition.&Canada:&John&Wiley&&&Sons&Inc.&
C.K.&Wang.&(1993).&Intermediate&Structural&Analysis.&New&York:&Mcgraw&Hill&Book&Company.&
R.C.&Coates,&M.G.&Coutie,&F.&K.&Kong.&(1997).&Structural&Analysis:&Third&Edition.&London:&Chapman&&&
Hall&
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