BANGALORE: Though Bangalore falls under seismic zone 2 - relatively less-prone to earthquakes - the city will be affected if there is a powerful earthquake with epicentre as far as 300 km away, warned Civil Engineering Safety Committee member of the Atomic Energy Regulatory Board S A Reddi on Wednesday.
"In Bangalore, tall buildings will definitely be affected," he said.
In the aftermath of the recent earthquake and tsunami in Japan, it's the Japanese's strict building codes that are better than those of other countries, which ensured the damage was less, he asserted.
"They have extra steel bracing, giant rubber pads and embedded shock absorbers. Along the coast, they have installed warning boards and well-marked escape routes," added Reddi.
In contrast, 90 per cent of our architects had no clue about earthquake resistance, while they had to put their foot down and impress upon building owners to have all these in place.
'Caution thrown to wind'
"In Bangalore, all the buildings have steel columns, no lateral resistance, especially at the ground floor level, which is most prone to a quake," lamented Reddi.
An upcoming 45storey structure being constructed by a reputed developer in Koramangala, according to him, had columns of 200 mm with not adequate space between bars. He said architects and designers should put in extra efforts in detailing and supervision.
While Bhuj came under zone 5 and Ahmedabad, which was 300 km away, under zone 3, the Bhuj quake in 2001 damaged more buildings in Ahmedabad, as they were taller and because of poor design and construction standards, claimed Reddi. Many parts of Karnataka fell under zone 3, he added.
He advised engineers to enclose parking areas will RCC walls on three sides and to enforce building codes.
"Also, avoid unsymmetrical plans and make sure two adjacent blocks are separated by enough space to avoid pounding. We also need bracing and shear walls," said Reddi.
It was better to use wood and steel in place of concrete in earthquakeprone areas.
"All civil engineers should have a basic understanding of the fundamentals of seismic design principles," he said.