An incredible 57-storey skyscraper was built in just 19 days using a special construction technique. The J57 Mini Sky City is located at Number 3 Broad Road in Changsha, the capital of China’s Hunan province. The city is known for its rich heritage, being home to the rare collection of excavated Western Han dynasty tombs known as Mawangdui, and its modern innovations, with this impressive tower, made entirely of steel features on that long list.
The J57 has no concrete core and is completely earthquake proof. It was developed by a building company, Broad Sustainable Building (BSB), with three levels constructed per day. The skyscraper was able to be complete quickly as 90% of it was prefabricted in a factory.
BSB specalises in prefabricated buildings. The construction method, which is a modern-day trick for making buildings in a blink of an eye, focuses on assembling structual components at a manufacturing yard. They are then transported to the site, and added to the building puzzle.
J57, which is 687ft tall and cost the region a whopping £1 billion to build, is home to 4,000 offices and 800 apartments. It also features a host of recreational areas, giving residents the chance to relax and socialise.
The spaces include a badminton and tennis court, a climbing gym, theatre and cinema, as well as a botanic garden.
The building provides luxurious living and working spaces in a convient location, just 15 kilometres from the airport and 13 kilometres from the city centre.
Sustainabilty and efficieny were aspects at the forefront of the construction process. The tower was built with energy-efficent, facotry-produced elements.
Additionally the use of the prefabrication method meant that the use of concrete trucks was reduced by up to 15,000 and the release of dust often associated with convential Chinese building processes was also avoided.
According to BSB architect, Xian Min, the construction method saved 12,000 metric tonnes of CO2 emissions compared to conveintial buildings with a similar function.
The remarkable multi-use building which occupies an area of over 180,000 square metres is an example of using less material and significantly reducing air pollution.
