Abstract
CN Tower, opened in 1973 reflects an impeccable structural of the modern world. It was constructed by use of concrete reinforced by steel pillars. At its time, the tower amazed many designers and engineers who consider it as the seventh wonder of the contemporary world.
It serves as a significant point for communications transmitting both radio and television signal due it its height. Indeed, it is the second largest freestanding structure in the world standing at 533.3m. Nonetheless, it would be safer, less laborious and cost efficient were the building constructed in the 21st century. The reason being improved technology.
Introduction
Despite the growing popularity of steel buildings and structures at the dawn of 20th century, CN Tower (a short name for Canadian National Tower) remains an iconic structure that combined both materials to rise above the heights of hitherto recognized tall towers. Located in Toronto, Canada, the building reflects an impeccable work of art and design that is inclusive of style and elegance. The tower stands at a height of 1,815 feet and weighs way above 130 thousand tons.
This massive tower is composed of huge amounts of concrete that has been strengthened by steel. It plays host to restaurants, offices and recreational facilities. This paper seeks to summarize the events that inspired its construction and the way in which the building was constructed. Besides, the paper will make recommendations on how best the building could have been built in the contemporary world.
Summary of Events and Factors
In consideration of other iconic towers in the world, CN Tower could be considered a modern building (Billington 43). The rationale is that the idea to construct the tower was inspired by the need for an effective communication tower that would serve Canada and act as a demonstration of superior Canadian construction and communication sectors. As such, the project began its construction in 1972 and Canadian Railways was the sole contractor of the project.
According to Fulford, many factors influenced the construction of CN Towers (3). First, the post World War II period saw numerous countries aim at establishing effective communication sectors that had the capacity to relay information for long distances with effectiveness, clarity and accuracy (Fulford 3).
For Canada, there was increased need to have a tower that would serve the growing number of the Canadian society. This, in the light of the truth that the tower could act as an antenna in which different communications firms could broadcast with more ease.
At the time, there was an apparent boom of skyscrapers in Toronto. First Canadian Place is one of the skyscrapers that were built in the 1960s. With the growing number of skyscrapers typifying Toronto’s skyline, communication was becoming increasingly challenging especially relaying signals to Canada’s downtown (Malcolm 61).
The skyscrapers would reflect the prevalent microwave links that were established at the time making it difficult for effective information reliance. As such, construction industry and communication saw the importance of building a tower that would surpass all the skyscrapers in terms of height.
Availability of raw materials (Concrete and Steel) was a huge precipitate during the construction of CN tower. While many architects and engineers advocated for use of steel at the expense of concrete, which had been popular in the medieval societies, the combination of the two went a long way in providing a cost effective structure. Besides, concrete structures had failed to live up to the expectations of civil engineers especially in construction of high-rise structures (Malcolm 74).
The rationale was that concrete became renowned for huge space consumption despite the structures inability to host increased numbers of facilities. Hence, use of steel was an alternative that many engineers could recommend. However, steel is not economically feasible due to its unavailability. CN Tower utilized both concrete and steel in an appropriate manner to save on the marginal cost of land utilization as well as cost of building.
Evidently, technological advances were apparent in the construction of the structure. Fulford says that the precision at which the tower was constructed reveals increased knowledge acquisition amongst the Canadian civil engineers of the time (34). Indeed, there has been a raging debate on whether or not the tower fits to be a world wonders. By the end of 20th century, the American Society of Civil Engineers concluded that the tower is indicative of a contemporary wonder of the world (Billington 31).
It implies therefore that the skills and competence of the engineers contracted by Canadian Railways Company was unparalleled. With the increase in technological advances, CN tower is an evidence of complex structure that incorporates many facilities while at the same time remaining a landmark for Canada.
Fulford articulates that Canadian society has a huge sense of elegance and the construction of CN tower only serves to assert the explicit needs of the Canadians to include aesthetics and functionality in their structures (Fulford 53).
It is therefore important to recognize that the tower was not only aimed at serving communication purposes alone but also display elegance that projects Canada and to large extents, Toronto as a tourist destination to the world (Billington 43). Additionally, the composition and utilization of the tower also reveals the increased aesthetics.
The construction of the tower also came at a time when the concept of sustainability of economic resources was taking root (Malcolm 21). Specifically, there was the need for engineers to utilize resources at their disposal in such a manner that the future generation’s ability would not be compromised. In this tune, Billington explicates that land remains a high-level resource that diminishes with increase in population (34).
CN tower therefore uses economized space of land to provide business with numerous offices and tourists with unsurpassed recreational facilities. Were the number of facilities in the tower constructed in conventional structures, it would imply increased use of land in an unsustainable way. As such, the construction of CN Tower was partially influenced by the need to use available resources sustainably and in this case, land resource.
Construction
Canadian Railways, the major contractors in the project made the groundbreaking at the beginning of February in 1973. The first part of the construction involved massive excavations to provide the tower with a firm foundation (Fulford 63). The foundation had the depth 49.2 feet at the middle.
With a circumference of well above 458 feet, it took the workers an average of four months to get through with the foundation (Billington 34). The technological advancements facilitated the fast tracking of the foundation with hydraulic excavators and other pulley systems put in place to enhance its completion.
Moreover, using hydraulic technology, the main support pillar was erected at the base of the foundation. In itself, it marked an unprecedented engineering feat that was composed of platform raised above with the help of jacks (Malcom 31).
The concrete at the bottom therefore was allowed to set as the process continued. With massive workforce that mainly provided manual labor, the pouring of concrete continued until the building surpassed amongst other buildings in terms of height. In sum, over 40,500 cubic meters of volume of concrete was poured in the tower. To maintain a vertical structure, the use of huge plumb bobs guided the concrete input throughout the construction period (Billington 45).
The second phase of construction began in the middle of 1974. The engineers utilized the initially installed hydraulic jacks to put in place a steel crown at the top of the building. Wooden brackets were used to guide concrete in to the tower.
In fact, pouring of concrete in the Sky Pod was fully facilitated by wooden brackets that acted as a guide through which the concrete could settle. As such, the sky pod that is above the rest of the tower was because of massive use of wooden brackets. Besides, the concrete was reinforced by use of steel bands that surrounding the building.
To live up to its objectives, the use of cranes to place an antenna at the top of the building was the main technology that the constructors. Coupled with use of helicopters such Sikorksy S-64 Skycrane, a model that been disposed of by the US military, the use of cranes was reinforced especially when placing the antennas in the tower’s sections.
Not to undermine the high technological advances during the construction of the tower, the use of helicopters in construction was an attraction on itself. At that time in history, the use helicopters in construction of buildings rarely happened. In this case, use of sophisticated machinery to complete the tower was critical given the size of the building (Malcolm 47).
It took only two years to have some initial plans of the tower scrapped. The Metro centre did not see the light of day owing to increased cost of construction prior to the initial budget. The consequence was a huge challenge for visitors who would not access the tower as earlier anticipated. The chief project architect John Andrews attributed the lack of completion of this center was due to poor selection of building space. However, after the completion and finishing the tower with amazing features that have continued to puzzle many.
At its opening in June 1976, the tower had cost the Canadian Railway an average of $243 million (Billington 23). The structure of the building composed of different sub structures some of which were not in the initial plan. The main structure is hexagonal with an average of six elevators operating. On the top of the tower is a 100 meters antenna that hosts many broadcast signals for radio and television.
Recommendations
It is unarguable that CN tower remains as one of the most iconic towers in the modern world. With no intentions of undermining the architectural and engineering design pertinent to the tower, there are different dimensions that the tower would take if it were built in the 21st century.
Primarily, the objective of the tower to become a host of numerous radio and television communication channels would not hold in the modern world. Given the fact that satellite transmission of information has taken root, the need for communication towers all over the world has reduced dramatically (Fulford 43).
As such, the structure ought to have considered ‘future’ advancements in technology before it embarked on the construction. With such a structure, there would be the need to have the building increase its useful space without having to utilize so many resources on the sky pod to serve analogue communication (Malcolm 54).
In the contemporary world, structures of such heights have been subsequently been replaced to serve as tourist attraction sites in addition to serving as include business and commercial centers.
Take for instance, Burj Khalifa, which is in UAE and stands as the tallest building in the world has provided a space for numerous business offices which in no way, have reduced its ability to attract tourists. Despite the elegance portrayed by the freestanding CN tower, much of the building materials and space have gone to waste, as the tower cannot allow occupation of the storeys beyond the first 20 storeys.
The construction of the sky pod had numerous disadvantages that hindered the utilization of cheaper resources. In fact, to set signal in various sections of the building, the use of helicopters was not only an expensive venture but also created shortage of financial resources at the disposal of Canadian Railway at the expense of priory-planned structures within the building (Fulfort 41). In particular, Metro center did not materialize as planned owing to misappropriation of resources.
The convergent sky pod within the tower allowed few if any structures that could provide support for the workers. As such, were we to construct the tower in the context of the modern world, the structure would be uniform from the ground to allow the ability of the worker to access the top without using expensive technologies.
Prompted by occurrences of fire disasters like the one that occurred Ostankino tower in 2000, CN tower was found to be lacking proper maintenance and critical safeguards that could avert fire disasters. As such, the tower ought to have been constructed with fireproof materials that have typified modern civil engineering.
This would also be coupled by a system that would conduct frequent inspections to establish any potential cause of fire. A modern building would have a sprinkler system that would not only reduce the probability of fires but also ensure that there are reduced damages in cases of fire outbreak. It would also consist of nonstop monitoring operation that indicates areas within the building that are prone to catching fire.
Finally, other stringent measures such as banning any inflammable appliances from the perimeters of the building to reduce unforeseen risks should have taken precedence were the building to be constructed in the 21st century. In sum, numerous ways to prevent fire spread have continued to characterize the current and modern structures helping them to be safer from fire disasters than earlier on.
At its completion, the building had utilized incandescent lighting system. Were the building to be constructed in the modern era, the lighting system would change dramatically to allow increased cost efficiency and environmental friendliness. Although the tower has had the entire lighting system changed to incorporate LED lighting system, the initial plan had prioritized on the use of bulbs, which do not only use huge amounts of energy but also present a challenge to the environment amid the growing concern of global warming.
In 2006, CN tower predisposed the residents of Toronto to a rare but dangerous situation. Due to its shape, the building attracted ice at its dome in winter.
This continued for a while making the entire sky pod to possess huge layer of ice. Unprecedented spell of wind that engulfed the city blew much of the ice to the surrounding. The ice was broken into massive blocks that threatened people, vehicles, and buildings that surrounded it. Indeed, it forced the local council to declare a safety perimeter around the tower to avert the danger of loss of life as well as property.
In the light of this factor, it is important to consider this factor if we were to think of CN tower as having been constructed in contemporary world. Hence, it would not only bear a different shape but also made of materials that do not attract ice and snow. The substructure such as the dome could have been in another style to reduce the possibility of allowing the gathering of ice around it during winter.
Finally, it is important to appreciate that the tower cost huge amounts of financial resources. In the contemporary world, many machines have replaced human labor, which was apparent during the construction of the building. In fact, Canadian Railway contracted around 2000 manual workers particularly during the excavation phase.
In the contemporary world, the work of excavation would only take machines a few days contrary to the four months that it took to dig up the ground and foundation. As such, were CN towers to be constructed in the 21st century, it would insinuate reduced use of human and time resources that were typical in the construction period.
Summary
In sum, CN tower that is also referred to as Canada National Towers reflects an impeccable work of architectural and engineering design. Combined with elegance and superior architectural outlook, the tower stands amongst the tallest towers in the world only coming second Burj Khalifa. Indeed, the building stands at 533.33 meters above sea level.
Increased need for effective communication, technological advances and cultural practices precipitated the construction of the building. Its construction commenced in 1973 and the use of technological advances was apparent. Massive human labor and such highly advanced technology like helicopters saw the structure that was mainly made of steel pillars and concrete rise above all other buildings in Toronto’s skyline.
Nonetheless, government’s lack of finding an appropriate land, poor utilization of space, lack of compliance to fire safety principles, shape and many other aspects of the tower have been phased out in the contemporary field of civil engineering and architecture. CN towers however remains an iconic work that brings numerous number of tourists to the country. Thus, the recommendations are in appreciation that the structure is unparalleled by many structures
Works Cited
Billington, David. The Tower and the Bridge, Princeton: Princeton University Press, 1983. Print.
Fulford, Robert. Accidental city: The transformation of Toronto, MacFarlane: Walter & Ross Press, 1995. Print.
Malcolm, Andrew. A New High for Disco in Toronto’s Tower, Irwin, New York: McGraw Hill Publishers, 1991. Print.