The demolition of infamous Supertech twin towers in Noida was done in just 9 seconds at 2:30 pm on Sunday, ensuring minimum damage to nearly buildings housing around 5,000 people. To raze the 100-metre-tall structures safely to the ground, the waterfall implosion technique was used.
The implosion technique is used in urban settings, where engineers tactfully remove the supporting structures of the building that brings it down upon itself. The debris will fall like a waterfall. This requires controlled use of detonators and explosives, which are drilled into the building that supports the structure.
This method brought down the 55,000 tonne of debris in seconds while ensuring buildings near the structures sustain no damage.
Edifice partner Utkarsh Mehta told PTI that experts are “150%” confident that the towers will come down safely, assuring residents of “no damage” except for minor cracks on outer paints and plasters of some buildings.
“The technique is chosen on the basis of three parameters — cost, time and safety,” he said.
Over 5,000 residents of Emerald Court and ATS Village — the two closest societies to the twin towers – have been evacuated. Around 2,700 vehicles belonging to them have been also removed from the premises. An exclusion zone has been created at a radius of up to 500 metres around the twin towers where no human or animal will be allowed, except for a team of Indian and foreign blasters engaged in the demolition.
Contractors will carry out repair jobs once the debris is cleared.
Mechanical sweeping machines, anti-smog guns, water sprinklers and sanitation workers have been deployed to clear dust after the demolition.
More than 3,700 kg of explosives was used to implode the twin towers.
Mehta said there are three techniques to bring down any structure. The diamond cutter technique would have taken two years to raze the twin towers and the cost would have been five times of the implosion method.
“There we would have to slowly cut down every column, wall and beam from top to bottom using cranes,” Mehta told PTI.
Robotic technique, however, would have caused a lot of noise and taken 1.5-2 years and affected the residents of nearby Emerald Court and ATS Village.
Has This Happened Before in India?
In Kerala’s Kochi, the waterfall implosion technique was used to blow up four high-rise buildings in 2020. Edifice Engineering used the controlled explosion method to bring down the buildings in Maradu after the Supreme Court ruled that the construction of the flats violated coastal regulations.
On January 11, 2020, at around 11.19 am, a series of small explosions went off at H2O flats. The 19-storey building collapsed. Alpha Serine broke double flats within a quarter of an hour.
On the second day, Jane Coral Cove, which was the big flat to break, was the first to fall on January 12 at 11.01 am. The 17-storey, 128-apartment Coral Cove fell in six seconds. Even though it was on the banks of the lake, the explosion was done with precision without even a handful of garbage falling into the water. It cost the government Rs 66 crore to demolish these four buildings.
The Supreme Court on August 31 last year had ordered the demolition of the Noida Supertech twin towers for violation of building norms in collusion with district officials, holding that illegal construction has to be dealt with strictly to ensure compliance with the rule of law.
(with inputs from agencies)