New Delhi, Mar 10: Strong winds could increase the risk of a catastrophic collapse of the temporary stage the Art of Living Foundation has built below design specifications for its cultural festival on the Yamuna floodplain this weekend, structural engineers said today.
The engineers, one of whom has analysed the structure's stability, say strong winds - predicted by the India Meteorological Department to strike Delhi this weekend - may subject the temporary stage to forces that it is not designed to tolerate.
Their concerns stem from a joint analysis earlier this week by the Central Public Works Department (CPWD) and Vintech Consultants, a private engineering firm, that has labelled the giant stage "not safe" because of its design and the type of materials used.
In a letter to Delhi police, the CPWD has said the stage is unsafe because it has been designed for a wind speed of 4.7 metres per second instead of the Bureau of Indian Standards' requirement of 47 metres per second.
"We cannot say what will actually happen to the structure in the event of strong winds in the area - but, yes, in a worst case scenario, disaster is a possibility," a senior engineer who was involved in the analysis told The Telegraph, when asked about the implications of the findings.
Over 8,000 amateur and professional musicians, young and old, playing flutes, harmoniums, guitars, sitars, tablas and violins are expected to take their places on the stage during the World Cultural Festival, to be inaugurated by Prime Minister Narendra Modi tomorrow evening.
Delhi Tent Decorators, the company that built the stage, has asserted that it has been constructed according to the required specifications and is safe. "More than 15,000 persons are here on the stage right now, rehearsing - it is absolutely safe," Anil Batra of the Delhi Tent Decorators said.
Batra said he could not understand why the CPWD had made adverse observations in its report to the police. But engineers say there may be reason to worry about the behaviour of the stage if strong winds hit the National Capital Region during the event.
"Building a structure at one-tenth design requirements is a serious violation," Ashok Nagpal, a professor of civil engineering at the Indian Institute of Technology, New Delhi, told this newspaper. "Wind speed may not touch 47 metres per second on the day of the event, but a structure should be designed for this speed."
A structure designed to hold hundreds, possibly thousands, of people - even for short periods such as three days - is assigned a number (1.5) that engineers call an "importance factor." The CPWD-Vintech analysis, based on computer simulations of the structure under various forces, has found that the stage will fail at even 4.7 metres per second when this importance factor is taken into account, according to the report sent by the CPWD to the police.
"The actual behaviour of the stage will depend on multiple factors such as the number of people seated, the direction and speed of the wind, the duration of the stresses that sections of the structure will experience, among others," Vinod Jain, managing director of Vintech Consultants, said.
The IMD said on Wednesday that parts of northern India, including Punjab, Haryana, Chandigarh, Delhi and western Uttar Pradesh could expect thunderstorms and strong winds between March 11 and 13 - coinciding with the dates of the festival.
"We can't say exactly what the wind speeds will be in the area during the weekend today. Accurate forecasts are possible about three hours in advance," a senior IMD scientist said.
