The Motera Stadium, now known as Narendra Modi Stadium is unique in many respects. Yes, it’s the largest cricket stadium in the world with a seating capacity of 1.10 lakh spectators and is the second largest overall. The total area of the stadium is equivalent to 32 Olympic-size football fields put together. Apart from this the stadium has several structural and architectural features too.
The stadium occupies 63 acres of land with three entry points. It contains 76 corporate boxes which contain 25 people each. The stadium has facilities of a 55 room clubhouse, Olympic size swimming pool, and 4 dressing rooms. Instead of floodlights at a cricket ground, it has installed LED lights on the roof. The stadium has a capacity of 3,000 cars and 10,000 two-wheeler parking.
The stadium was constructed in 1983 and renovated in 2006. However, the stadium was demolished in 2015 to rebuild a new stadium at an estimated cost of Rs 800 crore. The contract to rebuild the stadium was won by the engineering giant, L&T.
A unique feature of the stadium is the LED lights on the roof instead of the usual floodlights at cricket grounds. The LED lights are installed on an anti-bacterial, fireproof canopy with PTFE membrane that covers 30 out of 55 metres width of sitting area.
The stadium exists in tiers to accommodate smaller events and maintain the atmosphere for spectators even when the bowl isn’t full. These tiers carry through to the roof being crucial it acted structurally independent. The city of Ahmedabad is located in a level 3 seismic zone. Due to this volatility it was imperative the roof design be lightweight and seismically separate from the bowl to avoid compromising the roof in times of movement.
Walter P Moore performed a detailed design of the roof system. The roof was originally designed to be supported by a trichord compression ring. Walter P Moore proposed a lightweight and flexible tension/compression system which allowed the team to cut costs while simplifying connection and erection procedures. PTFE, or polytetrafluoroethylene, a Teflon-coated woven fiberglass, was stretched between a circumferential inner tension ring and an outer compression ring. These rings float between the bowl and the roof via radial cable spokes to allow for movement in time of seismic activity.