challenges faced during the construction of Burj Khalifa

 challenges faced during the construction of Burj Khalifa

Abstract

Burj Khalifa is considered a significant structure in Dubai. It is located in the center of Dubai City. It is also considered the symbol of the United Arab Emirates (UAE). It is the tallest building or tower globally with a length of 828 meters. The great height and amazing design of the tower is the first thing that comes in one’s mind when Dubai City is mentioned. Samsung C&T Corporation is the company charged with the construction of the tower, which began in 2004. The company anticipated that it would finish the construction by the end of 2008. However, it had to complete the construction in 12 months later because of the enormous challenges it faced (Abdelrazaq, 2012). Therefore, this report discusses the challenges faced during the construction of Burj Khalifa. Some of the challenges discussed are heat, wind, materials, mobility, speed, and earthquakes.

Background

Burj Khalifa is the tallest structure made by man in the world. It is considered a significant structure in Dubai. It is located in the center of Dubai City. It is also considered the symbol of the United Arab Emirates (UAE) (Subramanian, 2010). The tower is one of the success stories and achievements in engineering history. The company charged with making the designs of the tower is the Skidmore, Owings & Merrill Company. Designing of this huge building in the world was not short of challenges. However, it is important to note the tower has scooped more than 25 awards and made over 17 records.

Meredith & Kotronis (2012) observe that the engineers started to construct Burj Khalifa in 2004. The interior design and construction were completed in 2009 – five years later. The tower was launched in 2010 as one of the new development referred to as Downtown Dubai. The tower was constructed to be a mixed-use and large-scale centerpiece of the development. The motivation of the government to build this tower was inspired by the need to diversify its economy that is predominantly based on oil. It was also inspired by the increasing desire for Dubai to become a global hub and gain global attention. The tower was named after the president of UAE and the ruler of Abu Dhabi, Khalifa bin Zayed Al Nahyan.

Owings and Merrill and Adrian Smith of Skidmore designed the tower. The designers belong to an engineering firm that was also responsible of designing One World Trade Center and Wills Tower. NORR Group Consultants was charged with supervising the architectural aspect while Hyder Consulting was the supervising engineer. Burj Khalifa design is inspired by Islamic architecture of UAE, especially the Great Mosque of Samarra. The hotel space and residential aspects find expression in the Y-shaped tripartite geometry on the floor. The tower is designed in a way that it can withstand high temperatures during the summer, and it has eight escalators and 57 elevators.

Rendering to Abdelrazaq (2012), the project faced some financial inadequacies at some point, and it needed more economical and money support. Sheikh Khalifa made sure that the project continues by lending the engineers funding and monetary aid – this may be the reason why the tower was named after Sheikh Khalifa. The profitability concept behind the project has proved successful, as evidenced by downtown condominiums, hotels, and surrounding malls accruing a lot of revenue from the tower.

Challenges during the construction process

The success of building such a huge building in the world lies in seven challenges of construction. Even though there were challenges during the construction process, the designers and engineers tackled them one after the other, leading to the tallest building on the planet. This report discusses seven construction challenges. It will also reveals how these challenges led to significant technological innovations that can be applied anywhere else.

Mobility

The first challenge faced during the construction was how the skyscrapers would maneuver the stairs. The Equitable Life Building in New York faced the same challenge during construction in 1870 but is only 40 meters high. According to Russo et al. (2013), the engineers realized they needed to find an alternative way of making people climb higher faster because they wanted to continue adding more floors. The engineers turned to an obvious solution to move construction material and builders to the end of the building – the elevators.

According to the Director of the school’s Historic Preservation Program in Historic Preservation at Columbia, Professor Andrew Scott Dolkart, it was not easy for people to use stairs in the old building. The old buildings were dark; it was very winding to climb stairs. For instance, businesses on the fifth floor were not doing very well because there were no elevators. Since the emergence of elevators, it is now easy for people and goods and constriction material to be moved from the ground to their destination on the building to the last floor. However, early elevators were linked with one deadly fault – nothing would prevent them to fail after the failure of the hoist cable.

Equitable Life Building was made up of only seven stories while Burj Khalifa has 163 stories. Therefore, even the use of elevators during the construction of the Burj Khalifa was not efficient as its height would stretch the elevation technology to its elastic or absolute limit. It is important to note that it is not easy to move over 40,000 people in and outside the building. Therefore, the engineers decided to use the elevation idea to its extreme. Another challenge faced with mobility is the use of elevators to move 50 tons of mass, especially using the escalators that move at a maximum speed of 36km/h and move 120 floors within 50 seconds. As a remedy, the engineers introduced emergency brakes into the action to stop these elevators (Baker & Pawlikowski, 2010).

Materials

Materials availability, movement, and usability (compatibility) is not a challenge that only occurred during the construction of Burj Khalifa. It is a historical problem that also affected the construction of other taller buildings like Monadnock Building in Chicago (60m high) and the Flatiron Building in New York. For instance, the skyscrapers were guided by safety elevators to enable them to break through the barriers, especially when reaching 93 meters high in the case of the Flatiron Building.

According to Abdelrazaq (2010), the traditional materials used for building was not suitable to build and hold such a tall building like the Burj Khalifa. Keen attention and technology required to build this building since the soil in the UAE is too soft to support a vast building. The stones in the UAE were also not suitable for construction. To overcome this challenge, the engineers came up with a skeleton of the building that integrated the best of stones and steel. For instance, the construction consumed approximately 30,000 tons of still. The engineers embedded the steel into concrete – the artificial stone. They also designed the building in a way that the reinforced backbone made of concrete is covered with a high-tech curtain wall made of steel and glass. It is estimated that Burj Khalifa’s curtain wall cost almost 100 million dollars. The engineers tested many prototypes before selecting the final cladding. All these inventions happened to overcome the challenge of materials during construction.

Heat

The heat was another challenge that the engineer experienced during the construction of Burj Khalifa. It was challenging for them to prevent the baking desert sun from converting the site of construction and the building into a big oven. The steel catapulted the skyscrapers to the heights that cannot be seen clearly by ordinary eyes. The walls of the building could no longer hold the mass of the entire structure. This challenge is similar to the one experienced by engineers when they were building a United Nations Headquarter (155m high) in 1947 in New York. The architects wanted to build a glassed-building for the interior to be not only bright but also light. However, they were affected by heat (Poulos, 2014).

Willies Carrier invented a modern air conditioner. This invention would turn out to be a solution to the challenge of heat faced by engineers at Burj Khalifa. He designed a machine that could dry and cool hot hair by using a fine mist of cold water to make it wet. Therefore, the air conditioning made it easy for skyscrapers to rise higher the building even when the temperatures were too high. It is important to note that Dubai records a temperature of as high as 40°C. It also records an average humidity of around 90%, thus making this environment extreme for skyscrapers (Abdelrazaq, 2010). Therefore, to withstand the effect of a brutal desert sun, the designer built air conditioning into the glass skin.

For instance, the glass is made up of two coatings. The outside coating is made of titanium whose function is to capture UV rays and also making sure that it reflects it the way sunscreen does. However, it is important to note that this coating does not stop the IR rays radiating from the sand in the desert, thus the need for the second coating. It is made of silver whose role is to reflect back out of the building the IR rays. The reflection of IR and UV rays reduces the intensity of heat going through the building drastically. For instance, John Zerafa, the Façade Project Director, carried out a simple experiment using ordinary glass and discovered that the inside temperature is at almost the boiling point at 98 °C when the outside temperature is at 46 °C. The new glass panels solved the problem since they kept the heat out with a total of 24 °C (Nehdi, 2013).

Speed – competing with the set time

Another challenge was the failure to finish the construction of Burji Khalifa as planned. The engineers and designers had intended that the project that began in 2004 will be complete in 2008. However, the construction took 12 months more as it was finished in 2009 and launched in 2010. This challenge was not specific to the Burji Khalifa engineering project as it was also experienced with the construction of the World Trade Center – twin towers. Developers had to reach the dizzying height by addressing this problem since because any delayed day led to increased expenses.

The developers came with the idea of reducing the time of construction to the minimum levels possible. As a consequence, the developers used prefabrication segments of the building assembled at the site of construction. It is also important to note that these sections were built offsite and only shopped the prefabricated sections to the exact locations whenever necessary. This aspect presented another challenge of lifting the prefabricated sections, which had a mass of almost 50 tons. However, the developers used a revolutionary crane to lift the prefabricated sections to every corner as deemed possible.

This approach allowed the developers to finish several floors weekly. For instance, the developers molded the base of the revolutionary crane (kangaroo crane); they then inserted reinforcement bars made of steel and later poured the concrete inside. The molds were lifted after the concrete was set to the next level repeatedly. The revolutionary cranes were hoisted up by the steel cages. The builders faced another challenge when Burj Khalifa, which could only be solved by using a pump concrete. Therefore, Putzmeister came up with a high-pressure trailer concrete pump. The main purpose of this pump was to push the concrete higher than ever seen before.

Wind

Burj Khalifa was soaring higher. Therefore, the building was exposed to the wind, which threatened the construction process. Wind exploited every weakness available in the construction process of the building. Studies have shown that the skyscrapers are affected by a high-speed wind – it’s dangerous for them. The air creates mini tornadoes rushed around the construction site. These tornadoes are called vortices and result in several areas with low pressure sucking the building sideways (Aldred, 2010). It is important to note that the vortices get more dangerous when the skyscrapers get taller.

The wind has affected engineering works across the world as well. For instance, it presented a significant challenge to builders during the construction of Sears Tower (442 meters tall) in a windy city like Chicago. As a response to wind challenge, the builders turned the skyscraper inside out. When the builder reached more than 100 floors tall during the construction of the Sears Tower, the height exposed it to the enormous forces of the wind. Aldred (2017) notes that the traditional skyscraper made from steel generated a lot of problems as could not be useful amid the wind forces. For instance, the steel skeleton would bend in high winds as it was getting taller. Therefore, the architects invented a technology that helped them beat the wind – shifting the steel frames to the outside of the building from inside.

As far as Burj Khalifa is concerned, Bill Baker sought a way of beating the wind. Bill Baker, a SOM structural engineer, designed a way of deceiving the wind. He gave Burj Khalifa an unpredictable shape. This shape broke the hold of the wind on the building. According to Bill, he said that when they were designing the building, they were also designing the wind in the process. He said that the wind could behave in tandem with the shape of the structure of the building, making a tremendous difference (Xincheng, 2012).

Earthquake

After overcoming wind, heat, gravity, materials, and mobility, Burj Khalifa had to deal with the next big challenge – earthquake.  Most booming economies in Asia were struggling to show their wealth in the world. As a consequence, they desired super-tall skyscrapers to achieve this objective. However, Asian topography is not friendly to super-tall skyscrapers because of earthquakes. For instance, engineers had to contend with taking another leap forward to actualize Taipei 101. Studies have shown that earthquakes hit Taipei city two times a year (Baker & Pawlikowski, 2015). Therefore, when thinking about constructing the building of Burj Khalifa status, it is never a question of when the earthquake will strike, but it is a matter of when it will hit.

The builders needed to construct a building with a dash of elasticity to survive violent earthquakes. They constructed a building and made it flexible where necessary and rigid where it had to be. The building derived its strength from the stiff steel shoes filling the concrete. Even though the rest of the building is elastic, concrete-filled steel shoes form then columns that make it durable.

The massive reinforced concrete skeleton on Burj Khalifa makes it a firm building and can earthquakes. According to the designers, the structure can resist earthquakes of up to 6 when measured using a Richter scale. The next challenge that the engineers had to deal with was to come up with extraordinary measures to make the skyscrapers stand strong on the desert sand. For instance, there is a 3 to a 4-meter layer of sand below the ground where Burj Khalifa stands. As if this is not enough, the layer is followed by limestone and sandstones that cannot support any bigger structure. Scientists have stated that Burj Khalifa’s future, as well as its enormous weight solely, depends on a single scientific principle – friction (Bazler, 2017).

Evacuation challenge during an emergency

The skyscrapers become more vulnerable as they soared higher into the sky. Terrorism is one of the challenges that result in fears as far as threatening the very existence of skyscrapers. There was an increasing concern whether the skyscrapers would keep those who use them safe – this was a final leap of global technology in the engineering industry. Many people believed that the engineers would never build a super tall building, especially after the 9/11 incident.

It is important to note that it has never been an easy challenge anywhere as far as evacuating occupants from the skyscrapers is concerned.  The taller building presents a challenge whenever people are required to get to safe places. Therefore, the higher the construction goes into the sky, the further the occupants must move to safe destinations. Some people have observed that it is not easy for the rescuing personnel to make the occupants move down the stairs (Baker et al., 2010). People think that it easy to walk down the stairs than going up, but it is just as tricky as it is climbing the stairs. Therefore, during an emergency, nit everybody moves at the same pace – some move faster while others move slower because of physical fitness. Some occupants may be nursing injuries, and others may have lost their belongings like shoes. As a consequence, evacuation can never be smooth.

As far as Burj Khalifa is concerned with the safety of occupants, it is made up of a naturally fire-resistant concrete backbone for fire protection. For instance, a skyscraper may be two times the height of Twin towers. People may be wondering how the skyscrapers’ occupants get out in the event of the emergency – they don’t get out. It is also important to state that Burj Khalifa has nine refuge rooms set aside as special rooms. These rooms are made of fireproof sheeting and reinforced concrete. The walls of these special rooms can resist fire for a period of 2 hours. The rooms receive a special supply of air using fire-resistant pipes.

Similarly, the sealed fireproof doors make sure that smoke does not enter the rooms. Therefore, people in special rooms can stay there comfortably until the emergency services contain the fire. One can easily access these rooms because they are found every 30 floors.

The architects designed these rooms to demonstrate a fundamental concept in engineering. However, these rooms would not be safe if the only route that people can use to get there is blocked by smoke. Studies have shown that almost 98% of people do not die because of fire when there is a fire outbreak but smoke inhalation. The builders of Burj Khalifa thought of this concept and developed a technology that would take the smoke out of the equation (Baker & Pawlikowski, 2015). There are detectors and sensors on the building that can detect and sense heat and smoke when a fire is initiated kicking in a network of high-powered fans. The fans inject clean and fresh air in the entire building using fire-resistant pipes, forcing the smoke out and leaving the evacuation routes clear.

Conclusion

Burj Khalifa has become the tallest building in the world after it was launched on January 4, 2010. It is the tallest structure that human beings have ever built. The building stands on the shoulders of engineering wonders created by engineering giants. The building will continue to be an ultimate skyscraper until another bigger structure is built. Some of the challenges identified to have affected the construction include wind loads, which led to a structural challenge. Wind behavior and stress affected the construction process forcing the design team to carry out many wind tunnel tests (Aldred, 2010). The accessibility to, availability, cost, and compatibility of construction material was also a great challenge. This challenge forced the builders to mix ice with concrete. This approach also helps the engineers to overcome another challenge – heat. The mixture of ice and concrete was poured in the structure during the night, thus skipping the hot climate of the day. Cranes installed by specialists were also used to airlift large masses of materials from one level to the next.

Building Burj Khalifa was a daunting task that required high-tech equipment and heigh expertise. Even though many people thought that it would be possible to build taller buildings after the terrorists hit the pentagon in the United States during the 9/11 attack, Burj Khalifa is a demonstration of what man can do on this planet. It manifests the potential that human beings have of changing the world. It also demonstrates what engineers can do to bring a whole to life in a way that people can only imagine. The construction also shows that some of the best inventions in the engineering industry happen during challenging moments. It is only because of the challenges that builders had that they invented several measures to bring about the tower of Burj Khalifa.

References

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