India’s biggest controlled demolition of a building, a Noida high-rise, was carried out with excellent precision on Sunday, August 28. It happened nine years after a residents’ association went to court against the builders. Following a Supreme Court direction, the Supertech Twin Towers in Noida’s Sector 93A were reduced to rubble in a about 12 seconds.
With a display of breathtaking modern engineering, the illegal towers were razed using the implosion technique as a massive cloud of dust was formed.
The 100 m tall structures were razed, using 3,700 kilos of explosives bored into the pillars and walls of the two residential buildings, nearly a year after the Supreme Court found them in violation of building norms and ordered them to be razed. Let’s have a look at how the demolition process started and how it concluded.
The two towers – Apex and Ceyane – were rigged with over 3,700 kg of explosives. Explosives were inserted into nearly 7,000 holes in the pillars of the buildings and 20,000 circuits were set. The blast was planned to ensure that the towers fall straight down in what is called the “waterfall technique”.
The demolition exercise took place under a Rs 100 crore insurance policy to also cover damages to adjacent buildings, if any. Mumbai-based company Edifice Engineering was tasked with the demolition of the two towers.
The area had been evacuated hours ahead of the blast and measures put into place to ensure that adjoining structures were not affected by the explosion. Traffic diversions were planned and guidelines laid down to tackle any emergency.
The builders paid for the demolition, which cost about Rs 20 crore. A series of controlled explosions reduced the 100-metre tall structures to a mountain of rubble watched by thousands from surrounding rooftops and lakhs on live television.