India: Structural errors remain unrectified in quake-hit Ahmedabad
by Paul John
The 2001 earthquake had taught us the hard way how unsafe residential structures can turn into killers. More than 700 people had lost their lives when 77 buildings collapsed in a matter of seconds on the fateful morning of January 26.
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Eighteen years later, a preliminary Rapid Visual Survey (RVS) examination of 100 multi-storied structures by the Institute of Seismic Research (ISR) scientists in Rambaug area of Maninagar — where six buildings had collapsed — has found structures lurking with dangers. The survey indicated that “88% buildings had soft storeys, 51% had heavy overhangs, 48% had vertical irregularities while 29% were vulnerable to pounding effects of earthquake which is alarming.”
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Alarmingly, this time new development control regulations rules were in place but were apparently ignored. A senior Ahmedabad Municipal Corporation (AMC) official who shared the ISR study also revealed that of the 77 buildings which collapsed, new buildings have come up at 67 sites at the same same collapse sites. “Close to 90% of these buildings had soft storeys (hollow plinth) with no shear walls, 60% had overhanging structures like balconies jutting out, while vertical irregularity existed in nearly 40% buildings. Also, more than 35% buildings required moderate repairs and less than 5% buildings had issues of poor maintenance,” the official said.
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