UNIVERSITY OF LEEDS SCHOOL OF CIVIL ENGINEERING INTEGRATED DESIGN PROJECT – CIVE 1706 PROFESSOR BARRY G. CLARKE
THE FINAL DESIGN A THOROUGH STUDY OF WHAT DESIGN TO GO FOR
TEAM CLARKE MOHAMED MAHMOOD, BARROW TOURAY-SAWO, EMMANOUIL PAPADANTONAKIS, ETIENNE ALLEMAND, HARRY BETS, JOSH HOLLAND 25TH OF MARCH, 2011
Prof. Barry G. Clarke
The Final Design
Executive Summary Having a safe and functional design is a very crucial part in the process of project making. A structure that does not have the ability to perform in the way it should is a structure that has failed as it is not fit for purpose. This report is going to undertake a stud in order to finalize a design for an arch bridge that is going to be used in order to cross a 250 meter wide river. In order to initiate the design process it is very important to set aims and objectives. The challenge in this design project is to ensure that the structure is safe enough, architecturally well structured, and yet cost effective. In order to facilitate this process extensive research has been done. This ensures that the ground bases needed for designing the arch bridge are there. A precedent study is then done in order to gather on how to actually construct and design arch bridges, and what technical features are necessary. Finally, an option has been chosen to be the best fitting for our case. The option chosen is studied thoroughly and passes through two different stages of analysis. The analysis process is the core part which takes us to the final option that has been chosen. It is believed that the Gaidesville Bridge that is located in Sydney, Australia was the best option for the crossing that has been studied. Acknowledgments We are grateful to our tutor, Professor Barry G. Clarke for all the support and guidance that he gave us throughout the process of making this report. In addition we would like to thank all of the people who contributed in one way or another to the making of this report. A special thanks goes to the University of Leeds for giving us the opportunity of producing this report, which is the corner stone on which most of our reports will be based on in the near future.
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Table of Contents 1
1
Introduction
1.1
Aim
1
1.2
Objective
1
2
Specifications
1
3
Criteria
1
3.1
Health and safety
2
3.2
Cost
2
3.3
Construction
2
3.4
Environment and Sustainability
3
3.5
Materials
3
3.6
Building Services
3
3.7
Aesthetics
4
3.8
Rules and Regulations
4
4
List of Hazards
4
5
Crossing Options
6
6
Analysis
8
6.1
Hazard Analysing
8
6.2
Criteria Analysing
9
6.3
Analysis Output
9
7
Final Design
10
8
Appendices and References
11
8.1
References
11
8.2
Appendices
12
9
37
Bibliography
List of Figures and Tables 1. 2. 3. 4. 5. 6. 7.
Table 1: Client Specifications, Pg 1 (Appendix 1,13) Table 2: Criteria Summary, Pg 2 (Appendix 1, 14) Table 3: Hazard Analysis Summary, Pg 8 (Appendix 15, Derived from Appendix 2) Table 4: List of Bridges for final study, Pg 8 (Appendix 16) Table 5: Criteria Analysis Summary, Pg 9 (Appendix 13, Derived from Appendix 3-12) Picture 1: Sydney Harbor Bridge at Night, Pg 6 (http://www.trekearth.com) Picture 2: Side View of the Natchez Trace Bridge, Pg 7 (http://natcheztrace.thefuntimesguide.com) 8. Picture 3: View on Gladesville Bridge, Pg 7 (http://farm4.static.flickr.com) 9. Picture 4: Final Bridge Design, Pg 10
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1. Introduction Providing a safe and sound structure that is fit for purpose is one of the most crucial aspects in all projects. Structures must be able to minimize risks, and eliminate the hazards, yet, they have to meet all of the requirements set by the client. It is very important to pass through all of the mentioned steps in order to provide a stable structure that satisfies both the clients, and the safety requirements. The project outline was to design a crossing for a 250 meter wide river located in the North East of England. The structure is expected to be an architectural masterpiece as well as being a sound engineering structure. The crossing is also expected to be able to eliminate the hazards attached to constructing it and also to minimize hazards after the construction process, in order to be safe for the users who are going to use it. Hence, and aim and objective have been set in order to provide a guideline that can be followed during the process. The aim and objective are as follows: 1.1 Aim: The aim is to provide a design for a crossing that can cross a 250 meter wide river located in the North East region of England. 1.2 Objective: The structure of the crossing must be cost effective, architecturally iconic, capable of handling heavy traffic and to be ready to accommodate traffic within four years. 2. Specifications 1. A mode of crossing a 250m wide river. 2. The crossing must connect 2 double lane A-roads. 3. The crossing must become operational by November 2014. 4. The crossing must be functional (i.e. must enable the traffic of the two A-roads, plus pedestrians and cyclists to cross the river) 5. The crossing must be cost effective. 6. The crossing must make a statement. (must be either aesthetically innovative or structurally impressive) 7. The crossing must obey the National Highway Regulations. 8. The crossing must facilitate all waterway traffic that uses the river. (including 10.5m clearance in the case of a bridge) 9. The crossing must be accessible for building services and maintenance. 10. The crossing must be able to withstand weathering from the river and the climate and conditions of the North East of England Table 1: Client Specifications (Appendix 1, 13)
3. Criteria In this section the criteria that are used to determine the type of crossing and design of crossing are going to be discussed. The main criteria that are going to be used are as follows:
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1. 3. 5. 7.
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Client Specifications (refer to part 2) 2. Health and Safety Cost 4. Construction Environment and Sustainability 6. Materials Building Services 8. Aesthetics 9. Rules and Regulations Table 2: Criteria Summary (Appendix 1, 14)
The above criteria are going to be discussed and elaborated in the following pages in order to reach to a final decision. 3.1 Health and Safety: 1. Working with hazardous machinery. While on construction site heavy machinery such as bridge cranes, mixers and grinders are used, and in order to avoid any sort of delay in the project, and avoid injuries and deaths on site, working with such heavy machinery must be done with high care. 2. Amount of waste left behind. The amount of waste that is being deposited can vary depending on the type of construction and amount of materials used, and it is very important to minimize this, and make sure that the recyclable waste is being recycled appropriately. 3. Working in water. Working in water can be very dangerous, especially if there are high currents, this can cause injuries to the workers and hence delay the project. It is important to try and minimize working in water as to avoid any unwanted delays and injuries 4. Working with chemicals and radioactive materials. Working with such materials must be done with absolute care, as they can cause long term injuries, and affect the functionality of the workers. Working with such materials must be avoided, especially on construction site. 3.2 Cost: 1. Cost of material. Materials are one of the most important components for a structure. It is the building block of a structure. High quality material produces high quality product. 2. Cost of labour. To ensure that our structure stands in place we need to invest in labour ranging from various skills, to minimize errors and deliver an outstanding structure. 3. Cost of plant and equipment. Machinery plays a crucial role in lifting heavy materials such as precast concrete and heavy steel members. 4. Cost of Services. This ensures visibility at night or during bad weather conditions, such as fog. 5. Maintenance cost. It is important to oversee that the bridge is safe in terms of carrying vehicles and pedestrian loading. This involves testing reinforced concrete, and painting steel structures amongst other things. 6. Health and Safety costs. The project needs to comply with the health and safety at work (HASWA) act 1974.Employers’ liability act 1969 require employers to take out compulsory insurance against accidents and ill health to employees. 3.3 Construction: 1. Soil conditions. Soil conditions need to be studied while designing the crossing. It determines not only how the foundations will be built, but it will also facilitate the passage of ships and cargo. 2. Maximum load capability. The ability of the structure to withstand the load that it is going to face is very important as to avoid failure of the structure. The Load of live traffic including pedestrians and cyclists is to be included, and the stress applied due to weathering. 3. Weathering and drifting of soil. If there are strong currents in the area, the soil around the foundations can drift causing the foundations to move and hence making the structure unstable and prone to failure.
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4.
Material pallet. The choice of materials is very important as to provide a long term satisfaction for both the client and the users. 5. Services. It is important to consider the services that the structure will need such as ventilation and lighting while construction as to make preparations for such services. 3.4 Environment and Sustainability: 1. Water, ground and air pollution. It is very important to consider the amount of air, soil and water pollution that is caused by the structure as to keep the carbon foot print small. 2. Handling of dangerous materials. The amount of dangerous materials needed and how they would be transported/ disposed of – dangerous materials need to be disposed of correctly and safely otherwise they can cause massive harm to the environment 3. Handling of chemicals. The amount of chemical products used and the effect they have on the environment must be kept to a minimum in order to avoid hazardous pollution to the soil, water and wild life. 4. Disturbance of the structure to wild life. The deprivation of land/habitats – some habitats may be destroyed by the structure, if this is the case wildlife will have to find new homes or even die out in the area. 5. Noise and eye pollution. The usage of an appealing architectural structure as to avoid negative opinion of the structure. The amount of noise created during construction and while in use can affect the surrounding wild life and the residents of the area. 6. Availability of materials. The availability of materials in the surrounding area will reduce the transportation and hence reducing the amount of pollution caused by the structure. 7. Renewability of materials. The amount of renewable materials used – the more the amount of renewable materials are used the more sustainable the structure will be 3.5 Materials: 1. Cost of materials. The cost of materials is very important as to determine what material is used in the structure. Some materials such as steel can be much more expensive than other materials. 2. Density. The density of the materials plays a major role in the stiffness of the materials as to avoid unwanted vibrations and to get a safe structure. 3. Self weight. The self weight is very important especially in the case of a cable stayed bridge of a suspension bridge where the self weight must be kept at a minimum. 4. Sustainability. In is very important that the materials used are able to withstand their self weight and the weight of the live traffic and weathering in order to have a stable structure. 5. Durability. The long lasting of materials in important as to lower maintenance costs and avoid wear and tear of the materials used in the construction process. 6. Maintenance costs. The amount of maintenance that each of the materials need is going to directly affect the maintenance costs. It is important to avoid the usage of materials that need high maintenance. 3.6 Building Services: 1. Lighting. Lighting is very important to facilitate night vision and also in order to guide the users of the crossing in poor weather conditions. 2. Ventilation. It is important to ventilate the area in order to avoid fumes building in the area which might cause discomfort for the users. 3. Drainage. In case of flooding or heavy rain it is crucial to get rid of all of the excess water in order to avoid traffic jams. 4. Energy Supply. The only energy supply required would be electricity for lighting, and if needed ventilation.
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5. Access for Maintenance. It is important to make the structure easy to maintain as for future maintenance works. 3.7 Aesthetics: 1. Type of Architecture. The type of architecture used in order to design the structure is very important, as it is the main determinant of how the structure will look. 2. Lighting Used. Lighting is not only important for night vision, but it also can be used as a way of enhancing the look of the structure, and adding an effect to the structure as a whole. 3. Cladding of the structure. It is very important to consider the cladding of the structure as it protects the structure and hugely affects how it is going to look. 4. Scale of the structure. The scale of the structure when compared to the surrounding structure is very important as for it to fit in with in the context of the area. 3.8 Rules and Regulations: 1. Speed limits. The speed limits directly affect the amount of stress applied on the structure. It also is important from a safety point of view. 2. Width of road. The width of the directly affects the needed width for the structure, hence the amount of materials and finally the price. 3. Width of pedestrian pavements. This part also affects the width of the final structure and hence affecting the price and amount of materials used. 4. Highway signs. The amount of highway signs needed in order to inform the users of the structure are important as they affect the safety of the users, and makes the structure more users friendly. 4. List of Hazards During the process of construction and designing an arch bridge, there are many hazards involved that need to be considered in order to meet the health and safety rules and regulation, whether be it during the construction process, or when the final product is delivered. Below is a list of the hazards that can be faced during and after the construction process: 1. Crane accidents: Cranes are a crucial part in the construction site, especially if having to deal with lifting heavy parts, and fixing of some elements. Some types of bridge construction rely on crane usage very heavily, especially if the method of vertical rotation or the cantilever methods are used. The earlier is preferred as it reduces time needed to construct the structure. In addition it reduces the amount of formwork needed and the space needed. 2. Scaffolding accidents: Especially when dealing with high rise construction, the process of erecting and using the scaffoldings should be done with care in order to avoid any accidents. The earliest form of construction for the arch bridge involved usage of scaffoldings in order to support the structure when just casted. The method of centering, which is not a very popular method anymore is going to be avoided as traffic in the river can't be stopped, as scaffoldings need to be erected in the river in order to support the structure initially in the case of a concrete arch. 3. Heavy machinery: It is crucial to make sure that during the operation of heavy machinery such as earth movers the site is clear. It is important to do so in order to avoid any fatalities due to running over the workers. In addition, when such machinery is operated, it is done in proper lighting conditions. Heavy machinery is used in the bridge construction can involve earth movers, compactors, and piling rigs. These equipments are mainly used in the initial stages of construction, and especially while constructing the foundations of the bridge. Since
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it is an arch bridge, heavy weight foundations or piles might be used to provide the horizontal support and avoid the collapsing of the bridge. 4. Holes and excavations: It is important to well protect the holes whether in the ground or on a surface, and mark them clearly in order for the workers to be able to avoid them when not in use. Holes and excavations can be very dangerous during construction. They mostly appear during the initial stages of construction. Using piles in case of weak soil conditions can represent a better option as it avoids having large excavations on site and hence reducing the risk due to holes and excavations. 5. Collapses: Collapses on construction sites, especially when dealing with big excavations are a major hazard. In case of bridge construction, the collapses can be due to excavations or due to the formation of embankments and cuttings for the roads. The collapses can occur in the form of landslides, especially if the soil is over saturated or if it is weak. Collapses of soil can be avoided by using temporary retaining walls and struts if necessary. 6. Shearing of soil: Weak soils can be a great challenge on construction sites. Sufficient testing of enough samples must be made in order to provide enough information regarding the soil strength and the maximum load the soil can withstand before failing. This problem can be either avoided by choosing an optimal location where the soil is strong enough to withstand the load due to the thrust of the arches, or eliminating it by using foundations that reach bed rock. 7. Soil movements: Movements in the soil due to the compression or expansion can create major problems during and after construction. This problem is caused by the change in the moisture content of the soil. Soil movement can be a major problem in case the structure moves in different proportions, this can weaken the structure and make it prone to cracks and it may also lead to the failure of the structure in the case of the arch bridge. 8. Water Problems: Especially if having a high water table, the chances of water leaking to the surface is high due to the capillary effect. Water problems can create major issues on site. Problems may include movement of soil due to changes in water pressure, hence affecting the strength of the soil, delays due to the inability to pour the foundations in case of in-situ block foundations, and rusting of steel if the water leaks to where the steel members are stored. Water proofing is necessary to avoid this problem. 9. Fire hazards: On a construction site, where many materials can be flammable, it is very crucial to take caution when handling such materials in order to avoid any on site explosions that can delay the construction process and possibly cause fatalities. 10. Defective tools and equipment: All tools and equipment must be tested before usage in order to avoid usage of defective tools and equipment and hence causing delays of the construction process due to faulty readings or inability to operate some tools and equipments. 11. Water currents: Water currents can be one of the major hazards that can be encountered during the construction of the arch bridge especially some of the methods rely heavily on scaffoldings. This hazard can be eliminated by minimizing the amount of work needed to be done on water and using methods of construction such as vertical and horizontal rotation that involve using prefabricated parts and hence less work in the river. 12. Wind loading: Wind loading can be a major hazard both during construction and after. During construction poorly fitted form work or scaffoldings can easily topple over and collapse causing major delays and fatalities. This can be eliminated by ensuring that the safety requirements and being met. After construction, the structure is going to endure large amounts
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of wind loading especially if it is located in a valley area. This problem is automatically eliminated by the stiffness provided by both the deck of the structure and the arch that is supporting it. 13. Transportation of pre-casted and prefabricated parts: In the case of arch bridges offsite fabrication of parts such as deck sections and arch sections can be fabricated offsite and then transported on site where they are fixed together. The process of transporting these sections can be a very challenging process. On water transporting is the most effective way as it avoids putting the road users in danger, it is also more cost effective. The method of pre-casting sections can be resorted to as a final option if in-situ fabrication is not feasible. 14. Fixing of pre-casted or prefabricated parts: In the case of offsite fabrication, fixing of the prefabricated parts must be done with care in order to insure that each part is fitted properly with the other part. Fixing must be done with absolute care in order to avoid damage to the structure initially and to avoid failure of the structure in the future when the bridge is in use. 15. Form work: Especially if the cantilever of the centering methods are using, lots of form work must be used in order to insure that the structure is going to stand up. This can be eliminated by avoiding using such methods in the construction process and use the methods that involve usage of less formwork. 16. Construction waste: Waste due to construction can be a potential hazard to the environment, hence proper disposal of construction waste must take place in order to eliminate the risk of causing damage to the natural life. 17. Maintenance hazards: Maintenance must be facilitated by providing the necessary parts such as manholes in order to allow for future maintenance. Taking the time to make sure that they are all incorporated within the design of the bridge is going to reduce the risk faced by the person carrying out the maintenance in the future. 5. Crossing Options After Extensive research done on different types of crossings that are feasible to accommodate the traffic load and meet the requirements set, the option was opted to be an Arch bridge. The arch bridge is known for its ability to incorporate different architectural styles, and provide a safe structure as well. The arch bridge was chosen after assessing it against a wide range of criteria that included the client specifications. The set of criteria incorporated the construction process up to the aesthetics of the actual crossing. The different crossings have been graded, and the crossing that scored the highest was chosen, and in this case the crossing that had the ability to maximize all of the requirements is the arch bridge. Different examples of the arch bridge are now going to be studied in order to provide a more detailed view of how the final design of the crossing is going to be. Further assessment against the hazards and criteria is going to be done, and the final decision to be taken regarding which design is most suitable. The examples that are going to be assessed are as follows: Picture 1: Sydney Harbor Bridge at night 1. Sydney Harbour Bridge: Located in Sydney, [http://www.trekearth.com] Australia, the Sydney harbour bridge is a through arch bridge. The bridge in mainly constructed out of steel as shown in the picture above, this
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provides the main stiffness needed for the bridge. The arch that is made out using trusses and the two concrete towers represent the main architectural features of the bridge. Foundation wise, the bridge is constructed over huge block foundations that are set on either sides of the bridge. 2. Navajo Bridge: This Bridge is located in the state of Arizona in the Unites States. The bridge is supported by "concrete footings"[1] on both sides. The bridge is a simple deck arch bridge and steel forms the main material that is used in constructing this structure. The structure is very slender and light weight. 3. Natchez Trace Bridge: This Bridge is bridge is known for the way it blends with its surrounding as shown in the picture to the left. The main construction material is concrete, and it is constructed over a national park. The bridge used pre-casted sections that have been brought together on site. 4. Lupu Bridge: The Bridge that is located in Shanghai, China uses both concrete and steel as its main structural elements. The bridge uses plies that have been driven into the ground in order to solve the problem faced due to weak soil. Architectural wise, the bridge uses lots of lighting in order to Picture 2: Side view of the Natchez Trace Bridge enhance its structure. The bridge is a trough arch [http://natchez-trace.thefuntimesguide.com] bridge. 5. Silver Jubilee Bridge: A British example of an arch bridge. This bridge relies on the through structure in order to support its deck. Mainly made out of steel, the bridge has foundations set on water in order to support the arch and provide the horizontal strength needed. Architecturally, the bridge is very similar to the Sydney Harbour Bridge. 6. Rainbow Bridge: Located over the world's largest water fall, The Niagara Falls, this rainbow bridge is a deck arch bridge that mainly constructed out of steel. The arch is supported by rock on either side which reduced the need for large foundations. The name of the bridge is inspired from the rainbow produced by the splashing water due to the fall. 7. Gladesville Bridge: This Bridge relies on the basic roman way of arch construction. Hollow pre-casted concrete sections were carried on site and fixed over there. The bridge rests on sand stone from both sides which gives it the sufficient strength to withstand the load applied to it. This bridge is of the deck type arch bridge as shown in the picture to the left. 8. New Sivnesund Bridge: This Bridge that Picture 3: View on Gladesville Bridge connects the two Scandinavian countries, [http://farm4.static.flickr.com] Norway and Sweden is mainly constructed using concrete and steel. The arch bridge is of a half though type where the concrete arch is located in between the two box-girder decks. In order to solve the sub zero weather temperatures that the structure faces, the arch is heated from within which prevents frost from forming on the structure of the bridge.
[1]:http://enpub.fulton.asu.edu/structu res/slidecollection/thumbnails/Navajo
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6. Analysis This section is going to deal with the analysis of the different arch bridges that have been chosen in order to reach to a final design. The analysis is going to be divided into two sections, the first which deals with the hazards and eliminates the bridges that don't minimize the risks. After the hazard assessment further assessment is going to take place where the three bridges that scored the least in the hazard assessment are going to be assessed. This critical analysis phase is going to reduce the amount of options available and hence gives a clearer view of how the final design of the bridge is going to be. 6.1 Hazard Analysis: Based on the list of hazards the crossing options are going to be assessed. The scale on which this assessment is going to take place is a percentage scale, the higher the percentage, the higher the risk. This means that the aim is to minimize the average percentage awarded as this minimize the risk hence meaning that the bridge can eliminate the hazard. The grade awarded for each bridge is going to be based on the extensive research done on each bridge. The research included the method of construction, materials used, cost, impacts after construction and aesthetics. This extensive research allowed for more precise grades given for each bridge based on its features. This makes the final result much more accurate and fit for purpose. The summary of the results are as follows: Bridge
Percentage
Rank
Sydney Harbour Bridge
40.8%
4
Navajo Bridge
38.8%
3
Natchez Trace Bridge
29.4%
1
Lupu Bridge
48.8%
7
Silver Jubilee Bridge
48.6%
6
Rainbow Bridge
50.5%
8
Gladesville Bridge
38.4%
2
New Sivnesund Bridge
47.6%
5
Table 3: Hazard analysis summary (Appendix 15, Derived from Appendix 2)
As can be observed from the above table, the first was the Natchez Trace Bridge, second the Gladesville Bridge and third the Navajo Bridge. The first rank has been eliminated from the options list as it is not crossing a river. Even though the bridge has a very stable structure and is architecturally very appealing, but it can't be considered as one of the options that can be studied in the next part. The main reason that the Natchez Trace Bridge has been included is to show that the hazards regarding working on dry land are much more less, and can be eliminated easier. This makes the list of bridges going for the final assessment against the criteria: 1. Gladesville Bridge
2. Navajo Bridge
3. Sydney Harbour Bridge
Table 4: List of bridges for final study (Appendix 16)
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6.2 Criteria Analysis: Based on the hazard analysis, three preferred options have been opted to be the chosen design. These three options are going to be further analyzed based on the criteria mentioned above. This is going to refine the options furthermore, hence making the final design much more precise in meeting the client's requirements. The scale used in order to analyze the three options is going to be a percentage scale, where one hundred is the best, and zero is the least. Not only that, but the different criteria have different weights; hence the criteria having more weight will be dominant over the less weighed criteria in the list. After analyzing the three preferred options, the summary of the analysis is as follows: Sydney Harbour
Navajo
Gladesville
Client Specification
819
783
819
Health and Safety
483
486
480
Cost
344
440
520
Construction
390
300
395
Environments and Sustainability
304
328
300
Materials
336
476
406
Building Services
201
180
213
Aesthetics
80
54
80
Rules and Regulations
166
98
168
69.4%
69.8%
75.1%
Table 5: Criteria analysis summary (Appendix 12, Derived from Appendices 3-11)
The above analysis shows that the Gladesville Bridge is opted to be the most suitable design to fit the criteria of the clients. And meet the most Requirements. 6.3 Analysis Output: After analyzing the crossing options against both the hazards and the criteria the Gladesville Bridge has proven to have the most suitable design for the set crossing. The chosen design has scored 38.4% (ranked 2nd) in the hazard analysis, while it scored 75.1% (ranked 1st) in the criteria analysis. The design of the bridge is now going to be edited and refined in order to make sure it fits the crossing. Other features from other designs might be adapted depending on the client requirements set, yet the dominant features are going to be takes from the bridge that ranked highest in both analysis cases, the Gladesville Bridge.
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7. Final Design: The final design for the crossing has been decided to be a deck arch bridge. The design would be similar to that of the Gladesville Bridge that is located in Sydney, Australia. The bridge's main features would be the concrete deck, the box-girder used for the main deck and finally a set of columns that allow for the elevation of the actual deck for it to reach the required height as shown in picture number four bellow. The two arches are going to be hollow concrete arches that are casted on site. The bridge is going to be formed from two arches that start at both sides of the road and then meet up at the middle of the span forming an inverted "V" shape from both sides when seen in plan view. The set of columns are very crucial in Picture 4: Final Bridge Design order to provide the needed leverage of the main deck so that it would be raised enough to allow for it to rest over the arch. The columns also release some of the load off the arch hence allowing for a more light weight structure, therefore reducing the cost of the project. Foundation wise, the most suitable foundation for such a structure, considering the unpredictable soil conditions, would be driven concrete piles. The piles are going to provide the necessary horizontal forces for the arch to stand up. The way that the piles are going to work is by the shearing forces created around the pile when driven into the ground. The stiffness of the arch and the deck, added to it the extra strength provided by the columns is going to allow for the lateral wind loading without causing the structure to fail. The light weight design of the arch is going to minimize wind loading, and hence making the structure less prone to failure due to excessive lateral loading. In order to optimise construction, the cantilever method or the horizontal rotation method can be used. Both of the methods are going to be suitable since the arches are going to be casted in-situ. The horizontal rotation is preferred though as it involves less work done on the water surface which minimize the hazards of working in water. Cost wise, the bridge is supposed to cost between £4 million to £5 million. The low cost is due to the simple yet effective structure of the bridge. The Gladesville Bridge was "$9 million (in today’s dollars)"[2] and since both structures are about the same size and are of the same type, this gives an estimate of the cost of the final design of the crossing. The design chosen for the crossing is optimal because it minimizes the risk caused by the hazards, it is cost effective, aesthetically pleasing and it has the ability to withstand the load applied to it due to traffic and it has the ability to carry all of the services needed. Meeting all of the criteria makes the design an optimum choice for the 250 meter wide river that is located in the North East of England.
10 [2]:http://www.reocities.com/lockstar/ gladesvillebr.html
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8. Appendices and References 8.1 References: 1. allenpinto. (2005). Sydney Harbour Bridge. Available: http://www.trekearth.com/gallery/Oceania/Australia/East/New_South_Wales/Sydney/photo20 5378.htm . Last accessed 24th March 2011. 2. Bernard Shepherd. (2005). Gladesville Bridge. Available: :http://www.reocities.com/lockstar/gladesvillebr.html. Last accessed 20th March 2011. 3. enpub.fulton.asu.edu. (). Navajo. Available: http://enpub.fulton.asu.edu/structures/slidecollection/thumbnails/Navajo. Last accessed 13th March 2011. 4. Unknown. (2004). Gladesville Bridge. Available: http://farm4.static.flickr.com/3334/3649356014_0ac43aa728_o.jpg. Last accessed 24th March 2011. 5. Unknown. (2008). Natchez Trace. Available: http://natcheztrace.thefuntimesguide.com/images/blogs/natchez-trace-bridge-span.jpg. Last accessed 24th March 2011.
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8.2 Appendices: 1. Appendix 1: Feasibility Report
UNIVERSITY OF LEEDS SCHOOL OF CIVIL ENGINEERING INTEGRATED DESIGN PROJECT – CIVE1706 PROFESSOR BARRY CLARKE
FEASIBILITY REPORT A STUDY OF THE DIFFERENT OPTIONS
TEAM CLARKE MOHAMED MAHMOOD, BARROW TOURAY-SAWO, ETIENNE ALLEMAND, HARRY BETTS, JOSHUA HOLLAND, EMMANOUIL PAPADANTONAKIS 8TH OF DECEMBER, 2010 12
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Final Design
1.1 EXECUTIVE SUMMARY In the modern world ease of transportation became one of the most important aspects in each and every person's life, and hence the need for bridges, tunnels and flyovers rose in order to cross things such as rivers and mountains. The design project that is being worked on has the aim of designing a crossing that has the ability to cross a 250 meter wide river. The challenge in it is to make it as cost effective as possible, but yet it must be appealing to the eye, and also fit for purpose. This brings back the three main components of good design set by Vitruvius more than 2000 years ago. Extensive research took place in order to identify the available options that can be used, and some of the options have been omitted before the analysis stage as they did not meet the client's main requirements. Hence, an array of options have been studied, analyzed, and then a final option chosen that is most fit to purpose. After the detailed study of the different option the arch bridge has been chosen as the preferred option as it had the ability to meet most of the criteria set by the client, and the group. We believe that this option is the most desirable option as the arch bridge has the ability to transfer heavy load, can be very architecturally appealing, and is cost effective, hence following the three main concepts of good design.
1.2 ACKNOWLEDGMENTS We are grateful to our tutor, Professor Barry G. Clarke for all the support and guidance that he gave us throughout the process of making this report. In addition we would like to thank all of the people who contributed in one way or another to the making of this report. A special thanks goes to the University of Leeds for giving us the opportunity of producing this report, which is the corner stone on which most of our reports will be based on in the near future.
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1.3 TABLE OF CONTENTS
9.1
Executive Summary
i
9.2
Acknowledgments
i
9.3
Table of Contents
ii
9.4
List of Figures and Tables
iii
10
0
Body
10.1
1
Introduction
10.1.1
Aim
1
10.1.2
Objective
1
10.2
Specifications
1
10.3
Available Options
1
10.3.1
Bridges
2
10.3.1.1
Cable Stayed Bridge
2
10.3.1.2
Suspension Bridge
2
10.3.1.3
Arch Bridge
3
10.3.1.4
Beam Bridge
4
10.3.1.5
Truss Bridge
4
10.3.2 10.4
Tunnel
4 5
Criteria
10.4.1
Client Specification
5
10.4.2
Health and safety
6
10.4.3
Cost
6
10.4.4
Construction
6
10.4.5
Environment and Sustainability
6
10.4.6
Materials
7
10.4.7
Building Services
7
10.4.8
Aesthetics
7
10.4.9
Rules and Regulations
8
10.5
Weight of the Criteria
8
10.6
Analysis
9
10.6.1
Criteria Analysing
9
10.6.2
Preferred Solution
10
10.7 11
10
Preferred Option
11
Appendices and References
11.1
Appendices
11
11.2
References
15
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1.4 LIST OF FIGURES AND TABLES 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 14. 15.
Figure one: Non symmetrical harp cable stayed bridge, Page 2 Figure two: Suspension bridge, Page 3 Figure three: Arch bridge, Page 3 Figure four: Camel back multi-span truss bridge, Page 4 Figure five: Twin tunnel, Page 5 Table one: Client Specification analysis, Page 9 Table two: Health and safety analysis, Page 9 Table three: Cost analysis, Page 9 Table four: Construction analysis, Page 9 Table five: Environment and sustainability analysis, Page 9 Table six: Materials analysis, Page 10 Table seven: Building services analysis, Page 10 Table eight: Aesthetics analysis, Page 10 Table nine: Rules and regulations analysis, Page 10 Table ten: Total analysis, Page 10
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2.1 INTRODUCTION Different options need to be considered when designing a structure. The different options are then studied, evaluated and assessed based on an extensive set of criteria. At the end of the analysis of the different available options, a final preferred option is chosen that is going to satisfy all the criteria mentioned. We have been asked to study the different available options for a crossing or a two hundred and fifty meter wide river in the North East of the England. The crossing is to be architecturally and structurally sound, and it must meet certain criteria set by the client and by the group. Hence we have come up with an aim and an objective to follow during this process. Our aim and objective are as follows: 2.1.1 AIM: To design a structure that has the ability to cross a 250 meter wide river located in the North East of England. 2.1.2 OBJECTIVE: The crossing must be cost effective, make a statement, capable to handle heavy traffic and to be completed within four years. 2.2 SPECIFICATIONS 11. 12. 13. 14. 15. 16. 17. 18. 19. 20.
A mode of crossing a 250m wide river. The crossing must connect 2 double lane A-roads. The crossing must become operational by November 2014. The crossing must be functional (i.e. must enable the traffic of the two A-roads, plus pedestrians and cyclists to cross the river) The crossing must be cost effective. The crossing must make a statement. (must be either aesthetically innovative or structurally impressive) The crossing must obey the National Highway Regulations. The crossing must facilitate all waterway traffic that uses the river. (including 10.5m clearance in the case of a bridge) The crossing must be accessible for building services and maintenance. The crossing must be able to withstand weathering from the river and the climate and conditions of the North East of England. 2.3 AVAILABLE OPTIONS
Using several ways we can achieve that aim of crossing a 250 meter wide river. This part of the report will be focused on the different available types of crossings that can be used in order to maximize the objectives that we have got. Each type of crossing, i.e. Truss Bridge, will be discussed, and its features, advantages and disadvantages will be shown. This method makes it easier to compare between the different types of crossings that we have, hence making it easier to reach to a decision.
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2.3.1 BRIDGES 2.3.1.1 CABLE STAYED BRIDGE: One of the most attractive types of bridges is the cable stayed bridge. The main structural elements of the cable stayed bridge are the pylon, stays and the deck. The Deck is the part of the bridge that the traffic passes over. The deck is usually made of concrete or steel and in some special cases composite materials. The deck of the bridge should me stiff enough in order to resist the lateral loading from the wind, and that is the reason why concrete or steel is usually used. The deck of a cable stayed bridge is divided into sections, where each section is supported by a stay connected to the main pylon. The Stays of the bridge are the connections between the deck and the pylon. The stays are usually made of steel, as it is flexible enough to not fail when load is applied to it. The pylon is considered to be the main structural element of the whole bridge, since it is the element that is going to carry the whole weight of the bridge, and live load. The pylon is usually made using reinforced concrete. Most of the iconic bridges in the world are cable stayed bridges. This is due to their flexibility and ability to carry heavy live load. In addition, the cable stayed bridge can be very economical while constructing, as it only needs to be supported by one pylon, and there is no need for temporary supports in order to support the deck. The sleek designs of the cable stayed bridge made it one of the most popular bridge types in the world.
Figure 1: Non Symetrical Harp Cable Stayed Bridge
2.3.1.2 SUSPENSION BRIDGE: Known for its ability to withstand large spans, the suspension bridge has been used over the years as a means of crossing the widest rivers. The suspension bridge mainly consists of several structural elements; the towers, the main suspension cables, the suspender cables, and the deck of the bridge. It is important that the suspension bridge has two towers, as to support the main suspension cables that are going to carry the weight of the bridge and the live traffic. The main suspension cables are then connected to heavy counter weights fixed in the ground on both sides of the river. When the previous part is achieved, the suspender cables can be fixed and hence the sections of the deck. The Suspension bridge is known to be very flexible, and this is very important so that in case of earthquakes the structure will not fail.
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Construction wise, it is pretty expensive to construct a suspension bridge as there are two main towers and several counter weights that hold the bridge together. In addition, the construction of the bridge involves some temporary structures that need to be erected in order to facilitate the fixing of the main deck to the suspender cables. Due to its high construction cost, the suspension bridge is usually used in large scale projects only, but yet it remains as one of the most iconic bridges in the world.
Figure 2: Suspension Bridge
2.3.1.4 ARCH BRIDGE: Since developed by the Romans, the arch has been known to be a self sustainable structure; this means that the arch is not affected by the other members that are on top of it. The main structural elements of the arch are the arch itself, and the counter weights on both sides of the arch. The two counter weights that are on the sides of the arch are the main structural element as they avoid the arch from collapsing. Due to that reason, arch bridges are usually located in rocky areas, as they heavy rock can act as the counter weight behind the bridge, and prevent the structure from collapsing. The arch in the arch bridge can be either on above the deck level, or bellow the deck level. In case if the arch is above, the arch will act as similar to a suspension bridge, as cables will have to be suspended from the arch in order to support the main deck. If the arch is below the deck level, the deck of the bridge will be supported by the arch itself. The arch bridge can be very economical in during construction, as there is minimal amount of materials use, and this also can contribute to it being not as expensive as the cable stayed bridge and the suspension bridge
Figure 3: Arch Bridge
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2.3.1.5 BEAM BRIDGE: Known to be the most cost effective, and the easiest to construct, the beam bridge is one of the widely used structures, especially in flyovers and short crossings. The beam bridge mainly depends on two structural elements, the beam that supports the deck, and the columns that support the beams. The beam bridge is usually used for short spans, as if the span increases, there will be a need for more columns in order to support the longer spanning beams and prevent the bending moments. Due to its simple design, the beam bridge is also very easy to maintain – if designed correctly. It is not necessarily one of the most iconic bridges, but definitely one of the vastly used bridge types. 2.3.1.6 TRUSS BRIDGE: Depending on the simple truss as the main structural element, the truss bridge is one of the most commonly used in the rail bridges. The truss structure enables this kind of bridges to have a fairly large span. In addition, the truss bridge has a capability to bear heavy loading as it is mainly made out of steel. The truss bridge can be very efficient in construction, as the members can be prefabricated and then assembled on site. This reduces the time constrains and the amount of labour used while constructing the structure. The truss structure can be positioned either above the deck, bellow the deck, or if necessary, on both sides. The reason why this type of bridges in not usually used in large spanning bridges is that it does not have a very appealing look, and so other options that are more aesthetically pleasing are used, such as the cable stayed bridge, the suspension bridge, and the arch bridge.
Figure 4: Camel-Back Multi-Span Truss Bridge
2.3.2 TUNNEL A tunnel is a passage way that is completely covered, and is usually open at both ends in order to allow traffic to pass. The construction of a tunnel is a very long process, as it has several stages that start at the ground properties and end by the final construction of the tunnel. Sine tunnels need a fairly big time scale they are usually avoided, and hence we find fairly a small amount of tunnels around the world. When compared to bridges, tunnels are usually more costly as well, as their construction process takes more time, and more materials are needed in order to support the structure of the tunnel. There are several manners that can be used to construct tunnels, but for under water tunnels boring machines are usually used. A boring machine is a machine that excavates the ground in order to provide the space available for the tunnel to be constructed.
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The boring machine is one of the fastest ways that can be used in order to complete a tunnel. It is also cost effective as less labour will be needed in the excavating process. Even though tunnels are a very good way to provide crossings fro rivers, they can be very high maintenance, as said by Professor Barry G. Clarke in the annual geotechnical meeting held in the University of Leeds, "many tunnels have failed to fulfil their jobs" 1. Many tunnels leak from above, hence causing the tunnel to be shut down for maintenance which adds to the costs.
Figure 5: Twin Tunnels
2.4 CRITERIA
In this section the criteria that are used to determine the type of crossing and design of crossing are going to be discussed. The main criteria that are going to be used are as follows: 1. 2. 3. 4. 5. 6. 7. 8. 9.
Client specification Health and Safety Cost Construction Environment and Sustainability Materials Building services Aesthetics Rules and Regulations
The above criteria are going to be discussed and elaborated in the following pages in order to reach to a final decision. 2.4.1 CLIENT SPECIFICATIONS: 1. 2. 3. 4. 5. 6. 7. 8. 9. 10.
A mode of crossing a 250m wide river. The crossing must connect 2 double lane A-roads. The crossing must become operational by November 2014. The crossing must be functional (i.e. must enable the traffic of the two A-roads, plus pedestrians and cyclists to cross the river) The crossing must be cost effective. The crossing must make a statement. (must be either aesthetically innovative or structurally impressive) The crossing must obey the National Highway Regulations. The crossing must facilitate all waterway traffic that uses the river. (including 10.5m clearance in the case of a bridge) The crossing must be accessible for building services and maintenance. The crossing must be able to withstand weathering from the river and the climate and conditions of the North East of England. 20
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2.4.2 HEALTH AND SAFETY: 5. Working with hazardous machinery. While on construction site heavy machinery such as bridge cranes, mixers and grinders are used, and in order to avoid any sort of delay in the project, and avoid injuries and deaths on site, working with such heavy machinery must be done with high care. 6. Amount of waste left behind. The amount of waste that is being deposited can vary depending on the type of construction and amount of materials used, and it is very important to minimize this, and make sure that the recyclable waste is being recycled appropriately. 7. Working in water. Working in water can be very dangerous, especially if there are high currents, this can cause injuries to the workers and hence delay the project. It is important to try and minimize working in water as to avoid any unwanted delays and injuries 8. Working with chemicals and radioactive materials. Working with such materials must be done with absolute care, as they can cause long term injuries, and affect the functionality of the workers. Working with such materials must be avoided, especially on construction site. 2.4.3 COST: 7. Cost of material. Materials are one of the most important components for a structure. It is the building block of a structure. High quality material produces high quality product. 8. Cost of labour. To ensure that our structure stands in place we need to invest in labour ranging from various skills, to minimize errors and deliver an outstanding structure. 9. Cost of plant and equipment. Machinery plays a crucial role in lifting heavy materials such as precast concrete and heavy steel members. 10. Cost of Services. This ensures visibility at night or during bad weather conditions, such as fog. 11. Maintenance cost. It is important to oversee that the bridge is safe in terms of carrying vehicles and pedestrian loading. This involves testing reinforced concrete, and painting steel structures amongst other things. 12. Health and Safety costs. The project needs to comply with the health and safety at work (HASWA) act 1974.Employers’ liability act 1969 require employers to take out compulsory insurance against accidents and ill health to employees. 2.4.4 CONSTRUCTION: 6. Soil conditions. Soil conditions need to be studied while designing the crossing. It determines not only how the foundations will be built, but it will also facilitate the passage of ships and cargo. 7. Maximum load capability. The ability of the structure to withstand the load that it is going to face is very important as to avoid failure of the structure. The Load of live traffic including pedestrians and cyclists is to be included, and the stress applied due to weathering. 8. Weathering and drifting of soil. If there are strong currents in the area, the soil around the foundations can drift causing the foundations to move and hence making the structure unstable and prone to failure. 9. Material pallet. The choice of materials is very important as to provide a long term satisfaction for both the client and the users. 10. Services. It is important to consider the services that the structure will need such as ventilation and lighting while construction as to make preparations for such services. 2.4.5 Environment and Sustainability: 8. Water, ground and air pollution. It is very important to consider the amount of air, soil and water pollution that is caused by the structure as to keep the carbon foot print small.
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9. Handling of dangerous materials. The amount of dangerous materials needed and how they would be transported/ disposed of – dangerous materials need to be disposed of correctly and safely otherwise they can cause massive harm to the environment 10. Handling of chemicals. The amount of chemical products used and the effect they have on the environment must be kept to a minimum in order to avoid hazardous pollution to the soil, water and wild life. 11. Disturbance of the structure to wild life. The deprivation of land/habitats – some habitats may be destroyed by the structure, if this is the case wildlife will have to find new homes or even die out in the area. 12. Noise and eye pollution. The usage of an appealing architectural structure as to avoid negative opinion of the structure. The amount of noise created during construction and while in use can affect the surrounding wild life and the residents of the area. 13. Availability of materials. The availability of materials in the surrounding area will reduce the transportation and hence reducing the amount of pollution caused by the structure. 14. Renewability of materials. The amount of renewable materials used – the more the amount of renewable materials are used the more sustainable the structure will be 2.4.6 MATERIALS: 9. Cost of materials. The cost of materials is very important as to determine what material is used in the structure. Some materials such as steel can be much more expensive than other materials. 10. Density. The density of the materials plays a major role in the stiffness of the materials as to avoid unwanted vibrations and to get a safe structure. 11. Self weight. The self weight is very important especially in the case of a cable stayed bridge of a suspension bridge where the self weight must be kept at a minimum. 12. Sustainability. In is very important that the materials used are able to withstand their self weight and the weight of the live traffic and weathering in order to have a stable structure. 13. Durability. The long lasting of materials in important as to lower maintenance costs and avoid wear and tear of the materials used in the construction process. 14. Maintenance costs. The amount of maintenance that each of the materials need is going to directly affect the maintenance costs. It is important to avoid the usage of materials that need high maintenance. 2.4.7 BUILDING SERVICES:
6. Lighting. Lighting is very important to facilitate night vision and also in order to guide the users of the crossing in poor weather conditions. 7. Ventilation. It is important to ventilate the area in order to avoid fumes building in the area which might cause discomfort for the users. 8. Drainage. In case of flooding or heavy rain it is crucial to get rid of all of the excess water in order to avoid traffic jams. 9. Energy Supply. The only energy supply required would be electricity for lighting, and if needed ventilation. 10. Access for Maintenance. It is important to make the structure easy to maintain as for future maintenance works. 2.4.8 AESTHETICS: 5. Type of Architecture. The type of architecture used in order to design the structure is very important, as it is the main determinant of how the structure will look. 6. Lighting Used. Lighting is not only important for night vision, but it also can be used as a way of enhancing the look of the structure, and adding an effect to the structure as a whole. 22
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7. Cladding of the structure. It is very important to consider the cladding of the structure as it protects the structure and hugely affects how it is going to look. 8. Scale of the structure. The scale of the structure when compared to the surrounding structure is very important as for it to fit in with in the context of the area. 2.4.9 RULES AND REGULATIONS: 5. Speed limits. The speed limits directly affect the amount of stress applied on the structure. It also is important from a safety point of view. 6. Width of road. The width of the directly affects the needed width for the structure, hence the amount of materials and finally the price. 7. Width of pedestrian pavements. This part also affects the width of the final structure and hence affecting the price and amount of materials used. 8. Highway signs. The amount of highway signs needed in order to inform the users of the structure are important as they affect the safety of the users, and makes the structure more users friendly. 2.5 WEIGHT OF CRITERIA
In this section the weight of each of the criteria discussed in the previous pages will be discussed. The criteria will be ranked according to importance, relevance, and based upon the weight of the criteria, they will be multiplies so that they compromise of a greater value in the options analysis. It is very important to weight the criteria so that a more precise options analysis will be achieved and hence a better preferred option. Listed below, the criteria, their weight, and the reason for each criteria having being weighed that way. 1. Client Specification: It is very important to meet the client requirements, as without these requirements the project will not exist. Based upon that the client's specifications will be multiplied by a factor of nine (X9) in order to emphasis their importance. 2. Cost: Being one of the most important determinants in the whole process, the cost of the whole project is very important. Having a reasonable cost will also achieve one of the most important client requirements, which is that the design should be cost effective. Hence, the components of the cost will be multiplied by a factor of eight (X8) in the options analysis. 3. Materials: The materials form the core structure of the design, and so, they are a very important determinant on which will hugely impact the final design. Since materials are very important, they will be multiplied by a factor of seven (X7) while analyzing the options. 4. Health and Safety: During the recent years, health and safety has emerged as one of the most important factors in the process of designing a structure. Failures in the health and safety department can cause major delays to the whole project, and hence not being able to deliver on time. For the mentions reason, it has been decided that the health and safety will be multiplied by a factor of six (X6). 5. Construction: The process of constructing a structure is very important. The way it is constructed, the type of labour used, determines the end product and its quality. This means that the construction criteria and its sub criteria will be multiplied by a factor of five (X5) in the options analysis. 6. Environment and Sustainability: Taking care of the environment and appropriate disposal of waste is very important as to reduce the amount of pollution and the carbon foot print. Especially in our days where global warming is one of the most pressing issues, therefore the environment and sustainability criteria will be multiplied by a factor of four (X4) while analysing the available options.
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7. Building services: It is important to facilitate the structure with the important services such as lighting and ventilation, thus the building services criteria will be multiplied by a factor or three (X3). 8. Rules and Regulations: It is crucial to follow the rules and regulations that are set out, as if not followed, can cause the whole project to be stopped or delayed, and hence having an unsatisfied client. The rules and regulations criteria will be multiplied by a factor of two (X2) in our options analysis. 9. Aesthetics: Even though aesthetics are very important as to give an impression, but the structure should be fit in order to operate, and so the aesthetics criteria and its sub criteria will be multiplied by a factor of one (X1) in the options analysis. Based on the above weights of the criteria, the options analysis will be made in a more precise manner, and hence a decision which is fit to the purpose that it is need for. 2.6 ANALYSIS This section is going to address both the criteria and the available options. In this section, all of the available options will be assessed based on the criteria mentioned earlier, and hence finally reach to a final preferred option for the crossing of the 250 meter wide river. It is crucial to carry out this study of all of the available options in order to be able to reach to a final decision that is fit for purpose. The scale that will be used in order to assess the different types of crossings will be a scale from one to hundred (1-100), where one is the least and a hundred is the is most. 2.6.1 CRITERIA ANALYSING: 1. Client Specification:
Total
C-S 69%
Suspension 66%
Arch 85%
Beam 87%
Truss 79%
Tunnel 67%
Beam 81%
Truss 90%
Tunnel 68%
Beam 87%
Truss 86%
Tunnel 41%
Beam 73%
Truss 76%
Tunnel 52%
Beam 85%
Truss 87%
Tunnel 70%
Table 1: Client Specification Analysis
2. Health and Safety:
Total
C-S 76%
Suspension 71%
Arch 92%
Table 2: Health and Safety Analysis
3. Cost:
Total
C-S 61%
Suspension 57%
Arch 90%
Table 3: Cost Analysis
4. Construction:
Total
C-S 78%
Suspension 72%
Arch 87%
Table 4: Construction Analysis
5. Environment and Sustainability: C-S Suspension Total 81% 67%
Arch 90%
Table 5: Environment and Sustainability Analysis
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6. Materials: C-S 64%
Total
Suspension 63%
Arch 91%
Beam 90%
Truss 87%
Tunnel 68%
Beam 92%
Truss 91%
Tunnel 49%
Beam 74%
Truss 48%
Tunnel 77%
Beam 100%
Truss 100%
Tunnel 73%
Truss Bridge 84%
Tunnel
Table 6: Materials Analysis
7. Building Services: C-S 73%
Total
Suspension 74%
Arch 96%
Table 7: Building Services Analysis
8. Aesthetics:
Total
C-S 87%
Suspension 83%
Arch 89%
Table 8: Aesthetics Analysis
9. Rules and Regulations:
Total
C-S 89%
Suspension 89%
Arch 100%
Table 9: Rules and Regulations Analysis
2.6.2 PREFERRED SOLUTION: C-S Bridge Total
72%
Suspension Bridge 67%
Arch Bridge 90%
Beam Bridge 86%
61%
Table 10: Total Analysis
Based on the study that we have run, the different types of crossings have been assessed, and the results are as follows: 1. 2. 3. 4. 5. 6.
Arch Bridge Beam Bridge Truss Bridge Cable Stayed Bridge Suspension Bridge Tunnel
Hence, since the arch bridge earned the first place in the options analysis, the preferred method of crossing is going to be an arch bridge. The arch bridge suits the purpose best as it is cost effective, functional, and architectural elements can be incorporated within the design.
2.7 PREFERRED OPTION: As obtained from the options analysis, the preferred solution is an arch bridge. An arch bridge has is known for its ability to withstand heavy traffic conditions, in addition it is easy to incorporate different architectural elements in the design of the bridge. The arch bridge is the option nominated for the final design process as it has the ability to meet most of the criteria listed by the client and the criteria set out by the group.
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3 APPENDICES AND REFERENCES 3.1 APPENDICES: 1. Client Specification: Cable stayed Bridge
Suspension Bridge
Arch Bridge
Beam Bridge
Truss Bridge
Tunnel
250 Meters
85
56
93
93
92
72
Connect two Aroads
90
90
90
90
90
75
Completed by Nov 2014
70
70
85
90
85
75
Functionality
55
55
90
90
85
75
Cost effective
52
47
65
95
70
40
Meet rules & regulations
100
100
100
100
100
100
Must facilitate river traffic
80
95
80
50
50
100
Accessibility for maintenance
43
42
70
93
50
20
Erosion
43
40
90
80
86
50
69%
66%
85%
87%
79%
67%
Table 11: Client Specification Analysis
2. Health and Safety:
Working with hazardous machinery Waste left behind Working in water Working with chemicals and radioactive materials
Cable stayed Bridge
Suspension Bridge
Arch Bridge
Beam Bridge
Truss Bridge
Tunnel
56
59
93
94
86
42
79
32
89
77
93
30
70
93
85
53
81
100
100
100
100
100
100
100
76%
71%
92%
81%
90%
68%
Table 12: Health and Safety Analysis
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3. Cost: Cable stayed Bridge
Suspension Bridge
Arch Bridge
Beam Bridge
Truss Bridge
Tunnel
Cost of materials
42
36
90
91
88
27
Cost of labour
53
40
87
80
82
35
Cost of equipment
70
67
91
90
90
32
Cost of services
80
77
90
90
90
42
Maintenance cost
43
42
90
82
76
35
Health and safety costs
79
77
93
90
91
72
61%
57%
90%
87%
86%
41%
Table 13: Cost Analysis
4. Construction: Cable stayed Bridge
Suspension Bridge
Arch Bridge
Beam Bridge
Truss Bridge
Tunnel
Soil conditions
51
50
70
90
86
47
Maximum load capability
87
72
82
92
86
92
Weathering and soil drifting
77
73
90
50
61
45
Material pallet
90
90
97
43
54
32
Services
79
76
94
90
91
45
78%
72%
87%
73%
76%
52%
Table 14: Construction Analysis
5. Environment and Sustainability: Cable stayed Bridge
Suspension Bridge
Arch Bridge
Beam Bridge
Truss Bridge
Tunnel
Pollution
60
59
93
91
89
57
Dangerous materials
100
100
100
100
100
96
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Handling of chemicals
100
100
100
100
100
100
Disturbance to wild life
78
83
90
67
89
43
Noise and eye pollution
93
90
67
70
53
70
Availability of materials
52
48
90
96
87
53
Renewability of materials
87
87
89
71
92
73
81%
67%
90%
85%
87%
70%
Table 15: Environment and Sustainability Analysis
6. Materials: Cable stayed Bridge
Suspension Bridge
Arch Bridge
Beam Bridge
Truss Bridge
Tunnel
Cost of materials
42
36
90
91
88
27
Density
69
67
93
91
86
91
Self weight
67
70
91
89
88
88
Sustainability
100
100
100
100
100
100
Durability
66
64
86
91
87
71
Maintenance costs
43
42
90
82
76
35
64%
63%
91%
90%
87%
68%
Table 16: Materials Analysis
7. Building Services: Cable stayed Bridge
Suspension Bridge
Arch Bridge
Beam Bridge
Truss Bridge
Tunnel
Lighting
67
63
99
99
99
53
Ventilation
100
100
100
100
100
59
Drainage
78
76
92
89
69
42
Energy supply
69
67
98
97
97
46
28
Prof. Barry G. Clarke
Access for maintenance
Final Design
52
64
90
73
89
44
73%
74%
96%
92%
91%
49%
Table 17: Building Services Analysis
8. Aesthetics: Cable stayed Bridge
Suspension Bridge
Arch Bridge
Beam Bridge
Truss Bridge
Tunnel
Type of architecture
92
91
89
60
42
60
Lighting used
97
93
85
53
50
56
Cladding
90
92
92
92
53
91
Scale of the structure
71
56
91
92
46
100
87%
83%
89%
74%
48%
77%
Table 18: Aesthetics Analysis
9. Rules and Regulations: Cable stayed Bridge
Suspension Bridge
Arch Bridge
Beam Bridge
Truss Bridge
Tunnel
Speed limits
100
100
100
100
100
100
Width of road
83
81
100
100
100
73
pedestrian & cyclist pavements
71
73
100
100
100
51
Highway signs
100
100
100
100
100
63
89%
89%
100%
100%
100%
73%
Table 19: Rules and Regulations Analysis
2.6.2 PREFERRED SOLUTION:
Client Specification (X9)
Cable stayed Bridge
Suspension Bridge
Arch Bridge
Beam Bridge
Truss Bridge
Tunnel
621
594
765
783
711
603
29
Prof. Barry G. Clarke
Final Design
Health and Safety (X6)
456
426
552
486
540
408
Cost (X8)
488
456
720
696
688
328
Construction (X5)
390
360
435
365
380
260
Environments and Sustainability (X4)
324
268
360
340
348
280
Materials (X7)
448
441
637
630
609
476
Building Services (X3)
219
222
288
276
273
147
Aesthetics (X1)
87
83
89
74
48
77
Rules and Regulations (X2)
178
179
200
200
200
146
72%
67%
90%
86%
84%
61%
3.2 REFERENCES: 1. Bennett, David (1997). The Architecture of Bridge Design. London: Thomas Telford Ltd. p1200. 2. Klein, Jean-Francoise: Walther, Rene (1999). Cable-Stayed Bridges. 2nd ed. London: Thomas Telford Ltd. p1-320. 3. wikimedia Wekimedia, Available: http://upload.wikimedia.org/wikipedia/commons/7/7f/Cablestayed_bridge_pattern_german_1.png Last accessed: 16th October, 201 4. merriam-webster Available: http://visual.merriam-webster.com/images/transportmachinery/road-transport/fixed-bridges/suspension-bridge.jpg Last accessed: 29/10/2010 5. merriam-webster Available: http://visual.merriam-webster.com/images/transportmachinery/road-transport/fixed-bridges/arch-bridge.jpg Last accessed: 29/10/2010 6. Steel-bridges Available: http://www.steel-bridges.com/images/content/site_1/3b-bowstringmulti.gif Last accessed: 29/10/2010 7. Wikipedia Available: http://en.wikipedia.org/wiki/Tunnel Last accessed: 31/10/2010 8. Wikipedia Available: http://en.wikipedia.org/wiki/Tunnel_boring_machine Last accessed: 31/10/2010 9. Driving Instructor Training School – Train as a driving instructor. 2010. Driving Instructor Training School – Train as a driving instructor. [ONLINE] Available at: http. [Accessed 27/10/2010]. 10. Standards for Highways. 2010. Standards for Highways. [ONLINE] Available at: http. [Accessed 27/10/2010]. 11. . 2010. . [ONLINE] Available at: http://www.cehants.org/downloads/tunnel.png. [Accessed 31/10/2010]. 30
Prof. Barry G. Clarke
Final Design
12. Department for Transport (DfT) UK. 2010. Department for Transport (DfT) UK. [ONLINE] Available at: http://www.dft.gov.uk. [Accessed 27/10/2010]. 13. nameofbridge: Web Search Results from Answers.com. 2010. nameofbridge: Web Search Results from Answers.com. [ONLINE] Available at: http://www.answers.com/topic/nameofbridge. [Accessed 1/11/ 2010]. 14. Answers.com - What are some environmental problems linked with bridges. 2010.Answers.com - What are some environmental problems linked with bridges. [ONLINE] Available at:http://wiki.answers.com/Q/What_are_some_environmental_problems_linked_with_bridges . [Accessed 1/11/ 2010]. 15. . 2010. . [ONLINE] Available at: http://www.nrccnrc.gc.ca/obj/irc/doc/pubs/nrcc49675/nrcc49675.pdf. [Accessed 29/10/2010] 16. Highways Agency - Environmental impact and safety of highway tunnels. 2010.Highways Agency - Environmental impact and safety of highway tunnels. [ONLINE] Available at:http://www.highways.gov.uk/knowledge_compendium/76D0DA7E014749B08B014ACD1 21652DA.aspx. [Accessed 29/10/2010]. 17. . 2010. . [ONLINE] Available at: http://www.itaaites.org/fileadmin/filemounts/ovion/doc/safety/prague/LAG.pdf. [Accessed 01/11/2010]. 2. Appendix 2: Hazard Analysis Sydney Harbour
Navajo
Natchez Trace
Lupu Bridge
Silver Jubilee
Rainbow Bridge
Glades -ville
New Svinesund
Crane Accidents
76
74
22
66
67
22
43
79
Scaffolding Accidents
72
-
45
30
47
68
57
32
Heavy Machinery
86
84
21
47
85
65
74
65
Holes & Excavations
49
89
53
21
33
54
39
42
Collapses
41
82
21
39
35
37
24
72
Shearing of Soil
20
18
77
82
40
35
18
63
Soil Movements
14
-
56
85
37
20
12
71
Water Leakage
12
-
-
89
57
88
11
73
Fire Hazards
23
-
12
-
-
-
16
13
Defective Tools
36
63
21
62
54
58
40
37
Water Currents
30
-
-
20
50
91
28
-
Wind Loading
73
47
17
21
55
86
65
56
Transportation
-
-
52
60
32
29
-
75
31
Prof. Barry G. Clarke
Final Design
Fixtures
-
-
55
83
75
87
62
71
Form Work
65
71
16
46
61
21
63
21
Construction Waste
52
43
18
28
22
43
48
22
Maintenance Hazards
45
50
13
51
76
55
52
17
40.8%
38.8%
29.4%
48.8%
48.6%
50.5%
38.4%
47.6%
3. Appendix 3: Client Specification Analysis Sydney Harbour
Navajo
Gladesville
250 Meters
100
100
100
Connect two A-roads
100
100
100
Completed by Nov 2014
100
100
82
Functionality
100
76
100
Cost effective
66
93
71
Meet rules & regulations
100
100
100
Must facilitate river traffic
100
-
100
Accessibility for maintenance
84
43
92
Erosion
69
86
72
91
87
91
Sydney Harbour
Navajo
Gladesville
Working with hazardous machinery
71
52
78
Waste left behind
76
72
81
Working in water
45
100
62
Chemicals & Radioactive Materials
100
100
100
73
81
80
4. Appendix 4: Health and Safety Analysis
32
Prof. Barry G. Clarke
Final Design
5. Appendix 5: Cost Analysis Sydney Harbour
Navajo
Gladesville
Cost of materials
42
74
65
Cost of labour
34
40
62
Cost of equipment
47
35
51
Cost of services
72
42
73
Maintenance cost
61
55
69
Health and safety costs
62
25
67
43
55
65
Sydney Harbour
Navajo
Gladesville
Soil conditions
73
89
77
Maximum load capability
81
55
80
Weathering and soil drifting
63
64
68
Material pallet
76
52
79
Services
95
42
91
78
60
79
Sydney Harbour
Navajo
Gladesville
Pollution
67
85
62
Dangerous materials
100
100
100
Handling of chemicals
100
100
100
Disturbance to wild life
75
81
79
Noise and eye pollution
61
78
65
6. Appendix 6: Construction Analysis
7. Appendix 7: Environment and Sustainability Analysis
33
Prof. Barry G. Clarke
Final Design
Availability of materials
63
51
65
Renewability of materials
65
80
54
76
82
75
Sydney Harbour
Navajo
Gladesville
Cost of materials
45
88
56
Density
41
74
60
Self weight
32
79
48
Sustainability
49
45
51
Durability
62
66
65
Maintenance costs
61
55
69
48
68
58
Sydney Harbour
Navajo
Gladesville
Lighting
71
52
73
Ventilation
59
65
63
Drainage
62
66
67
Energy supply
60
63
62
Access for maintenance
84
53
92
67
60
71
Sydney Harbour
Navajo
Gladesville
Type of architecture
72
60
86
Lighting used
82
41
79
8. Appendix 8: Materials Analysis
9. Appendix 9: Building Services Analysis
10. Appendix 10: Aesthetics Analysis
34
Prof. Barry G. Clarke
Final Design
Cladding
81
-
78
Scale of the structure
83
62
79
80
54
80
Sydney Harbour
Navajo
Gladesville
Speed limits
85
61
82
Width of road
80
45
89
pedestrian & cyclist pavements
83
46
85
Highway signs
82
43
80
83
49
84
Sydney Harbour
Navajo
Gladesville
Client Specification
819
783
819
Health and Safety
483
486
480
Cost
344
440
520
Construction
390
300
395
Environments and Sustainability
304
328
300
Materials
336
476
406
Building Services
201
180
213
Aesthetics
80
54
80
Rules and Regulations
166
98
168
69.4%
69.8%
75.1%
11. Appendix 11: Rules and Regulations Analysis
12. Appendix 12: Final Analysis
35
Prof. Barry G. Clarke
Final Design
13. Appendix 13: Client Soecification 21. A mode of crossing a 250m wide river. 22. The crossing must connect 2 double lane A-roads. 23. The crossing must become operational by November 2014. 24. The crossing must be functional (i.e. must enable the traffic of the two A-roads, plus pedestrians and cyclists to cross the river) 25. The crossing must be cost effective. 26. The crossing must make a statement. (must be either aesthetically innovative or structurally impressive) 27. The crossing must obey the National Highway Regulations. 28. The crossing must facilitate all waterway traffic that uses the river. (including 10.5m clearance in the case of a bridge) 29. The crossing must be accessible for building services and maintenance. 30. The crossing must be able to withstand weathering from the river and the climate and conditions of the North East of England 14. Appendix 14: List of Criteria 1. 3. 5. 7.
Client Specifications (refer to part 2) 2. Health and Safety Cost 4. Construction Environment and Sustainability 6. Materials Building Services 8. Aesthetics 9. Rules and Regulations
15. Appendix 15: Hazard Analysis Summary Bridge
Percentage
Rank
Sydney Harbour Bridge
40.8%
4
Navajo Bridge
38.8%
3
Natchez Trace Bridge
29.4%
1
Lupu Bridge
48.8%
7
Silver Jubilee Bridge
48.6%
6
Rainbow Bridge
50.5%
8
Gladesville Bridge
38.4%
2
New Sivnesund Bridge
47.6%
5
16. Appendix 16: List of bridges for final study 4. Gladesville Bridge
5. Navajo Bridge
36
6. Sydney Harbour Bridge
Prof. Barry G. Clarke
Final Design
9. Bibliography 1. allenpinto. (2005). Sydney Harbour Bridge. Available: http://www.trekearth.com/gallery/Oceania/Australia/East/New_South_Wales/Sydney/photo20 5378.htm . Last accessed 24th March 2011. 2. Bernard Shepherd. (2005). Gladesville Bridge. Available: :http://www.reocities.com/lockstar/gladesvillebr.html. Last accessed 20th March 2011. 3. Brantacan. (2010). Construction of Arches. Available: http://www.brantacan.co.uk/construction.htm#Arch. Last accessed 15th March 2011. 4. Brantacan. (2010). Construction of Bridges. Available: http://www.brantacan.co.uk/construction.htm. Last accessed 15th March 2011. 5. Brian Gardner . (2009). Table of Historical Inflation Rates by Month and Year (19142010). Available: http://www.usinflationcalculator.com/inflation/historical-inflation-rates/. Last accessed 19th March 2011. 6. enpub.fulton.asu.edu. (). Navajo. Available: http://enpub.fulton.asu.edu/structures/slidecollection/thumbnails/Navajo. Last accessed 13th March 2011. 7. Klein, Jean-Francoise: Walther, Rene (1999). Cable-Stayed Bridges. 2nd ed. London: Thomas Telford Ltd. p1-320. 8. maccaferri. (2010). Slope Reinforcement. Available: http://www.maccaferri.co.uk/PAGES00203.html. Last accessed 15th March 2011. 9. Parsons. (2011). Arch Bridges. Available: http://www.partnershipborderstudy.com/pdf/Arch%20Bridges_2.pdf. Last accessed 19th March 2011. 10. S. Palaoro and E. Sivier. (2007). Concept and construction methods of arch bridges in Italy.Available: http://www.arch-bridges.com/paper2010/pdf/5Concept%20and%20construction%20methods%20of%20arch%20bridges%20in%20Italy.pdf. Last accessed 14th March 2011. 11. Standards for Highways. 2010. Standards for Highways. [ONLINE] Available at: http. [Accessed 27/10/2010]. 12. Unknown. (2004). Gladesville Bridge. Available: http://farm4.static.flickr.com/3334/3649356014_0ac43aa728_o.jpg. Last accessed 24th March 2011. 13. Unknown. (2008). Natchez Trace. Available: http://natcheztrace.thefuntimesguide.com/images/blogs/natchez-trace-bridge-span.jpg. Last accessed 24th March 2011. 14. Unknown. (2000). Arch Bridge. Available: http://www.pbs.org/wgbh/nova/bridge/meetarch.html. Last accessed 18th March 2011. 15. Unknown. (2004). Building the Sydney Harbour Bridge in 1930.Available: http://www.harbourbridge.com.au. Last accessed 13th March 2011. 16. Unknown. (2007). The Rainbow Bridge over the Niagara River. Available: http://niagarafallsmuseums.blogspot.com/2007/05/rainbow-bridge-over-niagara-riverwhat.html. Last accessed 12th March 2011. 17. Unknown. (2011). Svinesund Road Bridge, Sweden / Norway. Available: http://www.roadtraffic-technology.com/projects/svinesund/. Last accessed 16th March 2011. 18. Watson and Hillhouse. (2011). Piling Equipment Sales and Hire since 1972. Available: http://www.w-h.co.uk/uk/index. Last accessed 15th March 2011. 19. Wekipedia. (2010). Gladesville Bridge. Available: http://en.wikipedia.org/wiki/Gladesville_Bridge. Last accessed 15th March 2011. 20. Wekipedia. (2011). Svinesund Bridge. Available: http://en.wikipedia.org/wiki/Svinesund_Bridge. Last accessed 17th March 2011. 21. Zhixiang ZHOU. (2008). DEVELOPMENT OF AN ACCELERATED CONSTRUCTION METHOD FOR A CHORDED ARCH BRIDGE . Available: http://www.archbridges.com/conf2008/pdf/317.pdf. Last accessed 14th March 2011. 37