3,700-kg explosives, 'waterfall implosion' technique: How Noida twin towers will be razed under 15 seconds
Noida, August 27
The stage is set for the safe demolition of Supertech’s twin towers here on Sunday, in what is expected to be a breathtaking spectacle of engineering to raze down the nearly 100-metre-tall structures borne out of corruption.
Only last minute inspections remain as the towers—taller than Delhi’s iconic Qutub Minar—will be brought down in less than 15 seconds by waterfall implosion technique.
They will be the tallest structures yet in India to be demolished, officials said.
“All arrangements have been made and preparations done for the safe demolition of the twin towers as per schedule at 2.30 pm tomorrow,” Noida Authority CEO Ritu Maheshwari told PTI.
Over 3,700 kg explosives will be used to bring down the structures in pursuance of a Supreme Court order that found their construction within the Emerald Court society premises in violation of norms.
Around 5,000 residents of Emerald Court and adjoining ATS Village societies in Sector 93A have to vacate their premises by 7 am on Sunday while also removing nearly 3,000 vehicles and taking away 150-200 pets, including cats and dogs, with them for the day.
The closest buildings next to twin towers are Aster 2 and Aster 3 of Emerald Court society which are just 9 metre away. The demolition would be done in a manner so as not to cause any structural damages to other buildings, the officials said.
While nearby Noida-Greater Noida Expressway will be closed from 2.15 pm to 2.45 pm, the city will remain no fly zone for drones. The air space in one nautical mile radius above the blast will also remain briefly unavailable for flights during demolition time, according to Noida Authority.
All work related to placement of explosives and connecting them is already complete. The only work remaining is interconnecting the twin towers and placing a 100-metre-long cable from the structures to the exploder, from where the button would be pressed on Sunday, project officials said.
“Once last minute checks are done and all teams get down from the buildings, the two buildings Apex and Ceyane, have to be inter-connected. After that a 100-metre-long cable would be run from the towers to the exploder to demolish the buildings,” Edifice Engineering’s project manager Mayur Mehta said.
“Once we get the clearance from the police department that the exclusion zone is 100 per cent clear, then at 2.30 pm on Sunday we will press the button,” he said.
Mehta said only six people, including three foreign experts, Indian blaster Chetan Dutta, a police officer and himself, will remain within the exclusion zone to push the button for the blast.
Asked how confident he was regarding safe demolition, Mehta told PTI: “100 per cent. I don’t have any other word. We are 100 per cent confident.”
Mehta’s Mumbai-based Edifice Engineering has been tasked with safely pulling down the structures. Edifice has roped in South African experts Jet Demolitions for the project. The whole exercise is being overseen by the local Noida Authority.
Mehta has assured residents of adjoining societies that there will be no damage to their homes except for chances of “cosmetic cracks” on outer paint and plasters of some structures.
On how many options they had for demolition of the twin towers, Mehta said there are basically three techniques to safely raze down any structure of such a scale – diamond cutter, use of robots and implosion.
“The technique is chosen on the basis of three parameters – cost, time and safety,” he said.
He said the ‘diamond cutter’ would have taken over two years of time to completely demolish the twin towers safely, and its cost would have been five times of the implosion method.
On using robotics, he said this technique would have caused a lot of noise over a period of 1.5 years to two years and disturbed the residents of nearby Emerald Court and ATS Village.
“Its cost would have been less than the diamond cutter technique but more than implosion,” he said.
The Edifice boss said since the Supreme Court had also ordered that this project should be done in the shortest possible time and with no disturbance to neighbouring residents, the implosion technique became the choice for the project.
Diversions would be placed on roads leading to the twin towers in Noida Sector 93A from Sunday morning while the Noida-Greater Noida Expressway, barely 200 metres from the demolition site, would be closed for vehicular movement from 2 pm to 3 pm, DCP (Traffic) Ganesh Saha said.
Google maps will have updated feeds for diversions and real-time traffic situations on Sunday, Saha said, adding that arrangements have been made for movement of emergency vehicles.
DCP (Central Noida) Rajesh S said around 400 police personnel would be deployed for law and order duty, while PAC and NDRF personnel would also be on the ground for any contingencies.
Chief Medical Officer Dr Sunil Sharma said the health department would station six ambulances at the site equipped with officials and medicines. Beds have been reserved at the district hospital and private medical facilities Yatharth, Felix and Jaypee too.
The demolition of the twin towers will be carried out through the waterfall implosion technique which would bring them down within a few seconds literally like a house of cards.
The eye-popping event would leave behind a whopping 55,000 tonnes of debris, even as some estimates put the figure at 80,000 tonnes. The debris would take an estimated three months to be cleared and disposed of.
Maheshwari said all arrangements are being made to clear the dust from the area in the aftermath of the demolition.
Besides sanitation workers, mechanical sweeping machines, anti-smog guns, water sprinklers would be placed at the site, she said.
Residents of Emerald Court and ATS Village that PTI spoke to said they were anxious over the demolition, even as they expressed relief over the illegal structures finally set to go away after legal battles of more than a decade. PTI
