The soon-to-be world’s tallest building received its long anticipated groundbreaking ceremony on Saturday, July 20th. Developer Broad Group expects to complete constructing its basic structure and facilities by January 2014, Changsha local newspaper 三湘都市报 reports. Named Sky City, the 838-meter-high skyscraper will have 6 floors underground and another 202 towering in the sky in the town of Wangcheng close to Changsha. News of Sky City circulated around the world because of its stack-on construction methods and the concept of a building being a sustainable mini-city. TreeHugger explains:
“16,000 part time and 3,000 full time workers will prefabricate the building for four months and assemble on site in three months. The Broad system is based on prefabricated floor panels that ship with everything need to go 3D packed along with it, so they are not shipping a lot of air. It all just bolts together. BSC claims that by building this way, they eliminate construction waste, lost time managing trades, keep tight cost control and can build at a cost 50% to 60% less than conventional construction.
The design is based on the “bundled tube” structure, first demonstrated in the Sears (now Willis) tower and also used in the Burj Khalifa.”
Broad Group says that 280,000 parts of the 1.05 million square meter high-rise will be produced, managed, and will be constructed like airplane parts: “Ours will be 90% factory-made, which will take 20,000 workers 4 months to construct in the factory. Three thousand workers will work on on-site installations for 3 months. On-site construction is 10% of regular structures.”
What will Sky City be used for? The Telegraph briefly notes:
“Into that space, the developers will pack apartments, schools, shopping malls, theatres, cinemas, over 90 lifts and even a hospital. Sky City is also expected to boast a giant “vertical farm” that can provide food for the building’s 30,000-plus residents.”
According to Broad Group, here are the logistics:
The building will be 838 meters tall, the elevator will reach 830 meters, all with 202 floors above surface and 6 underground.
It will contain 4,450 households (the smallest apartment 60 square meters, the largest 520 square meters). The building will also have 250 hotel rooms, 100, 000 square meters of designated space for schools, hospitals, and offices.
An organic “vertical” farm will be 130 mu, and there will also be an 8,000 square meters for an outdoor “sky garden”.
A 10-kilometer long walk ramp (wide enough for cars to drive on) goes from the 1st floor to 170th floor.
56 column-less courtyards will each be 480 square meters and 10 meters tall. City plazas are planned (every 30 floors), along with children’s playgrounds, basketball, tennis, and badminton fields, swimming pools, movie theaters, and parks.
This grand concept also aims to be environmentally-friendly and ground-breakingly green, as explained in the TreeHugger article:
“The Sky City concept significantly reduces the per capita use of land, and the CO2 emissions generated getting around. They call it ‘a way of development for higher life quality and lower impact on the environment’. They see this as the future of Chinese city building: ‘Urbanization can not be materialized at the cost of land and environmental pollution.’
By going up, hundreds of acres of land are saved from being turned into roads and parking lots. By using elevators instead of cars to get to schools, businesses and recreational facilities, thousands of cars are taken off the roads and thousands of hours of commuting time are saved. It makes sense; vertical distances between people are a whole lot shorter than the horizontal, and elevators are about the most energy efficient moving devices made. A resident of Sky City is using 1/100th the average land per person.”
Broad Group claims that the structure can withstand a 9.0 magnitude earthquake and can endure high-temperature burning for over 3 hours. It seems that Sky City will be more like a self-sufficient community where its residents can eat, live, work, exercise, and study.