The ever increasing economic prosperity and population in the urban areas point towards a future where the construction industry is going to have to figure out a way to accommodate this monumental rise. With the availability of land for construction becoming scarce the architects and engineers are looking at innovative ways in which they can use the modern technology in the construction industry like virtual construction technology to their advantage and create taller buildings in small sites. This has today given a rise to the trend of super slender skyscrapers.
What are super slender skyscrapers?
The super-slender high-rise technique is an ingenious way of maximizing on available floor areas and gaining the most value from small sites. These slender skyscrapers are pencil-thin buildings of 50-90+ stories which use development and design strategy of slenderness to create buildings with maximum possible square feet of floor area.
The construction of slender skyscrapers first originated in New York with the building of structures like 432 Park Avenue and 53W53. Today many of these slender skyscrapers are clustered around Central Park particularly around the 57th Street which has been known as the Billionaire’s Row. These high-rise residential tower blocks have today achieved the price range of $9,000 to $11,000 per square foot. With these slender skyscrapers presenting attractive return on-investment the construction companies across the globe are looking to build such skyscrapers. Some notable examples being The Collins House site in Melbourne, South Quay Plaza in Tower Hamlets, Highcliff, in Hong Kong. However, to construct these skyscrapers is not without its own set of challenges, below we look at the challenges that engineers and architects face in constructions of these skyscrapers and how virtual construction is increasingly being used.
What are the key considerations and challenges in the construction of super slender skyscrapers?
The first challenge is to get the exact width to height ratio. When the term ‘slenderness’ is used it refers to the total height of a skyscraper, and well as its (base) width-to-height ratio. This could be extremely tricky to construct. Here there are various things which need to be kept in mind while designing and constructing such skyscrapers like measuring the effect of weather, quality of soil, looking at the materials as well as ensuring that the aesthetic appeal of the place is not lost.
Aerodynamics is another very important factor that the engineers, architects and designers must consider while creating super slender buildings. Wind is a dominant force and could lead to sway and thus early on in the designing phase different shapes for the towers need to be workshopped and then the designs need to be tested either in “wind tunnels” or through digital simulation. Then changes in the design are proposed like ledges and corners which are monumental in reducing the impact of the wind. The building could also be designed with holes, notches and slots which could be reduce the sway of the wind. With virtual construction the whole skyscraper can be constructed in a digital environment following which simulation can be used to simulate the effect of both the worst-case and as well as the general wind load on built structures. An alternative common method used by architects and engineers to reduce sway is use of mass dampers which can counteract sway and additional stability to the building.
Another key consideration which needs to be kept in mind while constructing skyscraper is the materials which are used for its construction. The popular combination of material used is steel and cement, which has allowed the architects to build slimmer, sturdier and more rigid structures. The builders were initially limited in the past but can today with new and strong materials build taller structures as well as maintain the building’s structural integrity. Recently researchers have found that by adding industrial by-products like ash, pulverized fly ash, leftover microsilica and steel slag could make the material more rigid and robust enough to support heavier loads.
Thus, we are living through the moment of history where the architecture and construction sector is going through some major evolutions. Super Slender Skyscrapers is a result of both the rising needs and scarcity of space made possible by technological advancements. The trend though has originated in New York it has slowly caught up in Hong Kong and Australia. It is however to be seen how these super slender structures will be constructed in countries with vastly different climate and soil conditions.