An Unorthodox Dissection of Structures with … Unorthodox Dissection of Structures with...

Student Competition, ASEE Zone 1 Conference, West Point, March 28-29, 2008

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An Unorthodox Dissection of Structures with Sophisticated Features

By Cory Gionet, Student, [email protected]

Mechanical Engineering Department, Union College, Schenectady, NY 12308 Advisor

Ashraf Ghaly, Professor, [email protected] Engineering Division, Union College, Schenectady, NY 12308

Abstract The design of sophisticated structures involves careful consideration of many technical and non-technical factors that influence their functionality. Buildings and constructed facilities do not only have engineering and architectural features but their design also requires an in-depth examination of impacting environmental, economical, historical, and cultural factors. Engineers are entrusted with the task of reconciling various view points in order to reach a consensus acceptable to all stakeholders. Artistic Engineering is a new course that explores the engineering and non-engineering aspects of structures. Students are asked to select a structure whose design embodies an insightful appreciation of the role each of the above factors plays in shaping the structure. Teams of two students, an engineer and a liberal artist, are charged with conducting a study that critically looks into the parameters considered in the design. A major component in this project is to dissect the structure and study what lies beneath its outer skin, including the foundation, skeleton, framing system, and other amenities. A requirement in this project is detailed three dimensional drawings of the structure and its various components using powerful software (SolidWorks) for engineering design and drafting which allows the user to view the assembled structure in a virtual space environment. The structure my team selected for this project was Dubai’s Burj Al-Arab, an engineering and architectural marvel that this paper will objectively scrutinize. The coupling of engineering and non-engineering students in each team complemented each other’s effort and helped create a climate of understanding that bridged the perceived gap between the two disciplines. Based on my experience, the assigned research methodology was greatly enjoyable and appealing. The course illustrated the interdependence of engineering and the liberal arts and developed a sense that integration is beneficial for the betterment of both disciplines. Introduction Structures are an essential component for the smooth functioning of all societies. Whether it is a home, school, hospital, road, or bridge, every structure serves some type of necessary purpose. This purpose is to make life for everyone as enjoyable and productive as possible. The design of any structure, no matter how small or large, involves the consideration of a number of technical and non-technical factors. Not only are there engineering and architectural aspects that must be addressed, but also economical, environmental, political, social, budgetary, and climatic factors that can exert a significant influence on what the final product (the structure) looks like. History is rich with examples of structures that have sophisticated technical features whose designs were also greatly impacted by non-technical factors. In many circumstances the debate and back and forth arguments about the non-technical aspects of a new project may take much longer than the time it takes to build the projects itself. Granted, some projects have a controversial nature such as bridges, towers, domes, dams, and tunnels, but these projects fall usually victim to passionate and emotional debates and less-than-factual public perception. A rational consideration of all influencing factors and a careful examination of all impacting parameters are the only way toward reaching decisions that are satisfactory to all concerned parties. It is usually the responsibility of the design engineer to comply with required codes and regulations, to harmonize conflicting viewpoints, and to find a common ground that is acceptable to all.


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Methodology A course entitled Artistic Engineering was structured to address a research methodology that examines the effect of engineering and non-engineering factors on the design of some of the most sophisticated structures ever built. The instructor showed examples of structures that, in addition to their sophisticated technical nature, the public scrutiny manifested by lengthy debates and tedious arguments were tremendous. The construction and the successful realization of every one of these structures were a triumph of engineering as well as a celebration of the skill of the design engineer in addressing all non-technical concerns related to the project. The instructor offered a different weekly theme in this course. Each of these modules included a class presentation detailing the history and other factors related to the design of the structure under consideration and a lab exercise. The instructor gave the students electronic SolidWorks graphic files for all the parts of the structure under consideration and a roadmap showing how to assemble all the parts to build the structure on a virtual 3D space platform. This exercise demonstrated how very complex structures are put together and the numerous parts that go into their construction. Students were required do a similar exercise every week. They were asked to select any structure of a nature similar to that covered in the theme of the week, write a research paper about that structure, build graphic files of the parts of the structure, and assemble the parts into a complete structure. Artneering was the title of the final project in this course where students were required to research and virtually build an existing structure with sophisticated technical nature as well as interesting non-technical aspects. This paper details the weekly assignments and the final project the writer did in this course. It shows how this unorthodox method of studying structures helps in developing an appreciation for the engineering and non-engineering aspects involved in the construction of these facilities. Course Themes The following are the major themes covered in the course: Preliminary 2D and 3DAssignments, Suspension Bridges, Cable Stayed Bridges, Towers, Structures with Extraordinary Nature, Domes and Shells, Water Regulating Structures, and Final Project. Preliminary 2D Assignment The preliminary assignment was intended to allow the students to familiarize themselves with SolidWorks platform. After a demonstration showing the basic functions of the software, each student was required to design and to draw a 2D plan view of a house with at least two bedrooms, a living room, a bathroom, and an attached garage. This gave the students an opportunity to use many of the basic features of the software, which served as a foundation for the much more intricate projects that would follow. Figure 1 shows the 2D plan view the writer designed and drew within this theme. Preliminary 3D Assignment Building on the previous week’s assignment, students were required to use the plan view developed for the house to add the third dimension and show their creation in 3D virtual space. This assignment enhanced students’ appreciation of buildings in 3D and illustrated the functionality of the software in addressing various design scenarios. Figures 2a&b show the un-roofed and the roofed, respectively, 3D model created in this theme. All drawings were produced with SolidWorks.

Suspension Bridges A suspension bridge consists of the following major components: the foundation, towers, anchorages, cables, main span, and the approach spans. The main principle behind a suspension bridge is that the main portion of the load is carried by the suspension cables that run from one anchorage, through the towers, and into the other anchorage. The Bronx Whitestone Bridge was the example used in the assignment of this theme. In 1905 the idea to build a bridge was proposed because residents of the area wanted a way to travel from Bronx, New York to Whitestone, Queens (1). However, it took until 1937 for John Moses’ proposal to be accepted by the state’s legislature as it became apparent that a bridge was needed for people to be able to get to the 1939 New York World’s Fair and LaGuardia Airport, and to reduce the


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traffic congestion that was taking place at the Triborough Bridge. The engineer for the project was Othmar Ammann. His original design for the Bronx Whitestone Bridge consisted of two 377 foot towers that had no diagonal cross bracing, which were the first not to have them. Ammann’s design was also unique because, unlike most suspension bridges at that time, this bridge did not have a stiffening truss system. In its place, Ammann used 11-foot I-beam girders to give the bridge an “art deco” look (2). The bridge was a total of 3770 feet long with a main span of 2300 feet making it the fourth longest main span in the world at the time. Presently, the bridge is the 37th longest span in the world. The bridge has two long suspension cables each 3965 feet in length that supported the main span. Each of the two cables has a diameter of 21¾ inches made of 37 strands of 266 galvanized steel wires. Each cable is anchored at each end of the bridge. Each anchor block measures 110 feet wide by 180 feet long by 110 feet high and weighs about 58 thousand tons. The bridge has four lanes of traffic and pedestrian walkways. It was completed six months ahead of schedule with construction only taking a total of 23 months. The final construction cost totaled $19.7 million. It opened on April 29, 1939 with a toll of 25 cents. Figure 3 shows an isometric view of the Bronx Whitestone Bridge produced with SolidWorks.

Figure 1. The plan view sketch of the house used in the preliminary assignment in SolidWorks.

Figure 2a&b. The isometric view of the inside of the house and outside of the house in SolidWorks.


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Figure 3. The isometric view of the Bronx Whitestone Bridge in SolidWorks.

Cable-Stayed Bridges A cable-stayed bridge is similar to a cable-suspended bridge in that the decks of the main and approach spans are suspended by cables affixed to towers. However, the unique characteristic about cable-stayed bridges is that their cables originate directly from the towers. Unlike cable-suspended bridges where there usually are main and secondary cables, all cables in a cable-stayed bridge are main cables that transmit the weight of the decks directly to the bridge’s towers. One extraordinary example of a cable-stayed bridge is the Sundial Bridge (3). When the city of Redding, California decided to have a bridge built over the Sacramento River, no one expected the city to choose the world renowned designer and bridge engineer Santiago Calatrava who is considered one of the most brilliant architects/engineers of his generation. His unconventional, beautiful designs have brought him to the forefront of architecture in the world today. Calatrava’s design is called the Sundial Bridge because it resembles an actual sundial. It consists of a 217 foot high pylon, a 700 foot long and 23 foot wide deck, 13 cables that attach the road to the pylon, and two foundation pieces that the pylon rests upon for support (4). It is a steel structure with galvanized steel cables and its deck is made of non-skid glass panels in a steel framework with granite accents. All this material totals a weight of 1600 tons for the bridge. The foundation consists of 115 tons of rebar and 1900 cubic yards of concrete. Since the bridge had to be located at this specific area, the lack of proper orientation prevented its functioning as a real sundial. For a sundial to show the correct time it has to be lined up with the Earth’s axis, which is not the case for this bridge. However, it is of interest to note that the bridge shows the correct time on one day of a given year, June 21. This is the day that coincides with the summer solstice. The dial plate at the bridge has hour markers from 10AM to 3PM. The pylon’s shadow moves across the plate at one foot per minute. The bridge opened on July 4, 2004 with a beautiful fireworks display. The bridge may be crossed from 6AM to midnight free of charge. Figure 4 shows an isometric view of the Sundial Bridge produced in SolidWorks. Towers The Eiffel Tower is made of iron and built next to the Siene River on the Champ de Mars in Paris. The tower gets its name from its designer Gustave Eiffel. The structure was originally built as the entrance arch for the Exposition Universelle, which was a World’s Fair, marking the celebration of the French Revolution (5). Construction of the tower began in 1887 and was completed in 1889. It was inaugurated on March 31, 1889 and opened on May 6, 1889. The tower is 324 meters high. The top roof is 300.65 meters tall with a 24 meter antenna on top. When it was completed in 1889, it became the world’s tallest


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structure, replacing the Washington Monument. The tower weighs a total of 7300 tons (6). Depending on the location of the sun, the tower may shift up to 18 centimeters due to thermal expansion of the metal. The tower can also sway up to 6 to 7 centimeters in the wind. Every seven years the tower has to be repainted which takes 50 to 60 tons of paint. Every time the tower is painted, three different colors must be used in order for it to look the same color from ground level. Currently the tower is used for radio transmission and as a tourist attraction. Since 1889, the tower has had over 230 million visitors, which makes it the most visited paid monument in the world per year. In 2006 alone, over 6.7 million people visited the tower. The Eiffel Tower is one of the most recognizable structures in the world and is well deserving of its popularity due to its beauty and grace. Figure 5 shows an isometric view of the Eiffel Tower as produced in SolidWorks.

Figure 4. The isometric view of the Sundial Bridge in SolidWorks.

Figure 5. The isometric view of the

Eiffel Tower in SolidWorks. Figure 6. The isometric view of the Taj Mahal in SolidWorks.

Structures with Extraordinary Nature There are countless examples of extraordinary structures in the world. These structures are masterpieces of engineering, architecture, and their creation manifests the importance of the cooperation of all those


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involved in the planning and development of such structures. One example of an amazing structure is India’s Taj Mahal. The Taj Mahal was built in Agra, India and is recognized as one of the wonders of the world. This beautiful structure was built during the Mughal Empire in memory of Emperor Shah Jahan’s favorite wife, Mumtaz Mahal (7). Taj Mahal has a very unique style combining elements from Persian, Turkish, Indian, and Islamic architectural styles (8). In 1983, Taj Mahal became a UNESCO World Heritage Site as one of the universally admired masterpieces. Ustad Ahmad Lahauri is considered the principal designer of Taj Mahal. Construction began in 1631 and was completed in 1663. The main focus of the structure is the white marble tomb with its arched shaped doorway and large dome top that is about 35 meters high. The dome is crowned by a gilded spire or finial that was originally made of gold, but is now made of bronze. The finial is supposed to represent the integration of traditional Persian and Hindu decorative elements. The base is essentially a cube that has four minarets/towers, at each corner that measure 40 meters in height. The interior decoration of the monument is just as elegant and magnificent. The garden that stretches across the land in front of the monument is also meticulously manicured. Taj Mahal is a tourist attraction in India visited by two to three million tourists a year. This figure includes over 200 thousand tourists from overseas. Figure 6 shows the isometric view of Taj Mahal created in SolidWorks for this theme in the course.

Figure 7. The isometric view of the Carrier Dome in

SolidWorks. Figure 8. The isometric view of the Glen

Canyon Dam in SolidWorks. Domes and Shells A dome is a type of structure that has either a half of a sphere or ellipse as a roof. One example of a domed structure is the Carrier Dome of Syracuse University, Syracuse, New York (9). Towards the end of the 1970s, the Syracuse football program was in jeopardy of losing their division 1-A status and was under pressure to improve their football facilities. Due to the cold and snowy climate of Syracuse, it was decided that the new stadium would be topped with a domed roof. The plan was passed and construction began in April of 1979. The dome was completed in September 1980 with the cost totaling $26.85 million. The Carrier Corporation donated $2.75 million as a naming gift, hence the name the Carrier Dome. New York State provided $15 million grant for the project. The dome is used for both basketball and football games for the university. It is the largest domed stadium on college campus and the largest domed stadium in the Northeast United States. It can hold up to 50 thousand people for football games and 33 thousand people for basketball games. Not only is it used for sporting events, but many concerts have been performed at the dome as well. Figure 7 shows the isometric view of the Carrier Dome as produced using SolidWorks.


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Water Regulating Structures Dams are used for flood control, hydropower generation, and as water regulating structures. Dams store water so that it can be used in times of need for purposes such as irrigation, drinking, and creation of habitats for wildlife. The Glen Canyon Dam located on the Colorado River at Page, Arizona is the example used for this theme of the course. The dam was constructed to store water for use in the arid southwestern United States, and to generate electricity for the region’s growing population. The dam has been controversial since its inception, because its lake (Lake Powell) flooded the scenic Glen Canyon area and its tributaries (10). The dam’s construction began in 1956. Although the dam was not dedicated until 1966, water storage began in 1963. The dam is 1560 feet long and 710 feet high. It is 25 feet wide at the crest and 300 feet wide at the base. The dam is made of 5 million tons of concrete. The Glen Canyon hydroelectric power plant, at the toe of the dam, comprises eight 156 thousand horsepower Francis turbines. The total nameplate generating capacity for the power plant is 1.3 million kilowatts. The dam provides power to nearly 650 thousand households in that area of the United States. Even though controversial, the dam is the major source of water and power in its surrounding area. Figure 8 shows the isometric view of the Glen Canyon Dam as produced using SolidWorks. Final Project Arabic for “Tower of the Arabs,” Burj Al Arab (Figure 9), located in Dubai, United Arab Emirates, is well-known for being the tallest hotel in the world, hovering at a breathtaking 321 meters above the Arabian Gulf on its own man-made island (11). This artificial island is located 280 meters out from Jumeriah beach and is connected to the mainland via a private bridge (Figure 10). Burj Al Arab was designed to resemble the billowing sail of an Arabian vessel known as a dhow, bending slightly in the wind. The construction of Burj Al Arab was overseen and managed by the Jumeirah group (12).

Figure 9. The isometric view of the Burj Al Arab in SolidWorks.


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Figure 10. A real life photo of the Burj Al Arab. Figure 11. The back support of the Burj

Al Arab in SolidWorks.

In 1994 construction of Burj Al Arab began under the supervision of British architect Tom Wright and was completed in 1999. The architectural and engineering consultants for the project were provided by the UK’s largest multidisciplinary consultancy, Atkins. The hotel construction was then carried out by South African construction contractor Murray & Roberts, at a cost of 650 million dollars. Since the hotel rests on an artificial island, which was constructed 280 meters offshore, the builders had to drive over 250 concrete piles, 40-meters in length and 1.5 meters in diameter into the sand as a foundation for the island to be created (13). The foundation was then held in place by the friction of the sand and silt along the outer surface of the length of the piles. A significant recommendation was that the pile design be based on the results of constant normal stiffness direct shear tests. This scientific approach was a notable departure from the conventional empirical design methods. Following the installation of the piles, a surface layer of large rocks was created, which was used to protect the foundation from any form of erosion. The building contains over 70 thousand cubic meters of concrete and 9 thousand tons of steel. The exoskeleton of the building features steel wrapped around a reinforced concrete tower (Figure 11). Diagonal space trusses made of steel are strategically positioned to reduce the effect of potential earthquakes and seismic activities on the skeleton of the tower (Figure 12). The sail of the dhow with the two “wings” is spread into a V-shape, forming a large space which is enclosed by a Teflon-coated fiberglass sail, which curves across the front of the building, creating the world’s tallest atrium (14). Inside the building, the atrium is 180 meters tall. During the construction phase, to lower the interior temperature, the building was cooled by half-degree increments over a period of three to six months. This was to prevent large amounts of condensation which could actually lead to real rainfall inside the hotel (14). This task was accomplished by several cold air nozzles, which point down from the top of the ceiling, and blast a 1 meter cold air pocket down the inside of the sail. This creates a buffer zone, which controls the interior temperature without massive energy costs. The “sail” is made of a material called Dyneon, which spans over 161 thousand square feet, consists of two layers, and is divided into twelve panels and installed vertically (14). During day light hours, a light white sheet on the fiberglass allows a soft and milky light to gently invade the hotel. Had this glass been simply clear, the front would have produced blinding glare and the temperature would have increased to uncomfortable levels. The Burj features several external structures which contribute the lavish luxury of the complex. A suspended helipad supported by a cantilever is located at the top of the building.


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Figure 12. Diagonal supports in SolidWorks. Figure 13. The Tennis court in SolidWorks.

The helipad, at a height of 211, is sometimes converted into a grass tennis court (Figure 13) for world famous tennis players. Oddly, the helipad has no borders or fences on the edges, so any tennis ball hitting outside of the perimeter of the tennis court would simply plunge to the ground or the sea. The outdoor swimming pool is lined with sea-toned marble and is surrounded with palm trees (Figure 14). While the Burj is considered to be a symbol of Dubai’s rapid urban transformation, it is also a lavish symbol of wealth and luxury (14). From its meticulous attention to details to its extravagant levels of comfort, the Burj is intended to show that its wealth and grandeur are unparalleled by any other hotel facility on earth. While the hotel has officially been given a 5-star rating, the creators of the Burj have self declared it to be the only 7-star hotel in the world, and thus making it one of the most coveted destinations on the globe.

Figure 14. Outdoor pool and bar in SolidWorks.

The service and unseen luxury which make it stand out from other 5-star hotels include Rolls Royce limousine service, private reception desks on every floor, helicopter pad with helicopter trips to the center of Dubai or to the Dubai International Airport, 9 world class dining restaurants, including one located 200 meters above sea level with an amazing view of the city, free entry into a water park, swimming pools, golf facilities, water sports, spa, and health club. The hotel suites feature white Tuscan columns and spiral staircases covered in marble with iron gold leaf railings and spa like bathrooms accented with mosaic tile patterns. Promoters claim that over 9 thousand square meters of gold leaf, marble, granite, and crystal have been used in the interior decor of the Burj. Expectedly, this luxury comes with a price tag up to fifteen thousand dollars a night. Despite its size, the Burj holds only 28 double story floors which accommodate 202 bedroom suites. The suites range in size from 169 square meters to 780 square meters. The rate of the Royal Suite, the largest room in the hotel, is 28 thousand dollars a night. Like anything else that leaves a mark on the world, the Burj Al Arab building has its fair share of controversy and


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criticism. Many argue that the structure is simply an ostentatious display of wealth and opulence and that it symbolizes the triumph of money over practicality. While some of the measures the creators of the hotel took to ensure the comfort of their guests might have been unnecessary, the goals of those who envisioned the hotel were certainly met, for Burj Al Arab has definitely become an icon for the Gulf Emirate of Dubai, symbolizing not only the architectural transformation taking place, but also the wonders of newly found levels of luxury. Conclusions In light of the given examples and the methodology used in teaching the present course, students were able to conclude that: 1. The design of constructed facilities requires careful consideration of both technical and non-technical

factors. Historical, political, environmental, economical, budgetary, and climatic factors are as equally important in the design of structures.

2. Public scrutiny and perception of complex projects can significantly alter the initially envisioned design and may result in significant changes to accommodate conflicting viewpoints.

3. The approach of researching the history of structures, then virtually building them on an advanced software platform is practical and useful in developing appreciation for the effort invested in addressing various design and planning aspects of a given project.

4. SolidWorks is a powerful tool that can help create realistic models of structural parts and assemblies. Its use in the present course complemented the theoretical learning experience with a hands-on one.

Bibliography 1. “Bronx Whitestone Bridge.” 23 September 2007. Wikipedia. 29 September 2007.

<http://en.wikipedia.org/wiki/Bronx_Whitestone_Bridge> 2. Herman, Ralph. “Bronx-Whitestone Bridge.” 29 September 2007. <http://www.nycroads.com/crossings/bronx-

whitestone/> 3. “Sundial Bridge at Turtle Bay.” 5 October 2007. <http://www.visitredding.com/sundial.cfm> 4. Scott Mobely. “Sundial Bridge is 217-foot feather in Redding’s cap.” 12 October 2007

http://web.redding.com/specials/sundial/stories/history.shtml> 5. “Eiffel Tower.” 18 October 2007. <http://en.wikipedia.org/wiki/Eiffel_Tower> 6. “The Official Site of the Eiffel Tower.” 18 October 2007. <http://www.tour-eiffel.fr/teiffel/uk/> 7. “Taj Mahal.” 25 October 2007. <http://en.wikipedia.org/wiki/Taj_Mahal> 8. A. Zahoor and Z. Haq. “Taj Mahal, Agra, India.” 25 October 2007.

http://www.islamicity.com/Culture/Taj/default.htm> 9. “Carrier Dome.” 1 November 2007. <http://en.wikipedia.org/wiki/Carrier_Dome> 10. “Blen Canyon Dam.” 7 November 2007. <http://en.wikipedia.org/wiki/Glen_Canyon_Dam> 11. “Burj Al Arab.” 10 November 2007. <http://en.wikipedia.org/wiki/Burj_Al_Arab> 12. “The Burj Al Arab Jumeirah.” 14 November 2007. <http://www.burj-al-arab.com/> 13. “Emporis: Burj Al Arab.” 12 November 2007. <http://www.emporis.com/en/wm/bu/?id=burjalarab-dubai-

unitedarabemirates> 14. “The Bur Al Arab Hotel: Tourist Magnet of Dubai.” 13 November 2006. <http://www.dubaihotel.ws/> Biography Cory P. Gionet is a sophomore in the Mechanical Engineering Department at Union College, Schenectady, NY. His main interests are computer and mechanical design, and athletics. He is a member of the Union College Baja Team and of Union College’s chapter of Engineer’s Without Borders. After graduation, he hopes to specialize in the field of automotive engineering, and he also intends to pursue higher degrees in mechanical engineering.

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