Iran Asks ‘Why Are Our Earthquakes So Deadly?’
Tue Dec 30, 1:22 PM ET
By Erik Kirschbaum—Reuters
TEHRAN (Reuters) – Poor design, primitive materials and widely ignored building codes were prime causes of the high death rate in the Bam earthquake, Iranian officials and foreign experts said on Tuesday.
In stark contrast to a tremor of similar strength last week in California that killed just two people, the toll in Friday’s Iranian quake could reach about 50,000.
Iran’s building codes have been tightened after quakes in recent decades killed tens of thousands. But officials and independent scientists say enforcement is woefully inadequate.
Bahram Akasheh, geophysics professor at Tehran University, noted the California quake on December 22 had almost the same magnitude and depth as the Iranian tremor, which measured 6.3 on the Richter scale and was centerd 16 km (10 miles) below ground.
“The question is why were only two killed in California but so many in Iran?” he said. “The answer is simple. The type of construction is totally different. There are building codes here but they are not followed. The laws are there, but only in theory. No one pays any attention. No authorities control construction.”
President Mohammad Khatami said there would be an inquiry and anyone who had violated state codes would be punished. Two hospitals, a prison and other state buildings collapsed or were badly damaged.
“We will investigate the houses which were built in recent years, especially government buildings,” Khatami said. “These buildings shouldn’t have collapsed. Those who are to blame will be seriously punished.”
While Iranian officials keep a close eye on many aspects of daily life, there is little policing of construction.
“I don’t think there are any shortcomings with our policies and construction codes,” said Mohsen Rezaei, secretary of Iran’s powerful Expediency Council.
“It is the construction managers who do not implement the codes. There is not enough supervision of construction and engineering.”
Ali Bakhshi, a civil engineering professor in Tehran, said some builders disregarded the codes to make bigger profits.
MUD-BRICK BLAMED
Fingers are also being pointed at the mud bricks common in towns like Bam. They are cheap and popular because they keep houses cool in summer and warm in winter. But they crumble easily, suffocating many who survive the actual quake.
“In Iran…the houses are essentially made of dust,” said Enzo Boschi, president of the National Institute of Geophysics in quake-prone Italy. “When buildings made of concrete collapse there are pockets of air where you can breathe and survive two, three, maybe even five days. But with mud houses, and the dust they produce when collapsing, you die much quicker.”
But experts say that is only part of the problem. They warn even Tehran, where modern steel-framed concrete buildings are common, would be vulnerable to quakes of around 6.0 on the Richter scale. A reading of at least 7.0 is often seen as the threshold for major loss of life.
With suitable construction methods, cities can survive much greater earthquakes. A tremor measuring 8.0 caused just 500 injuries and no deaths in Japan in September.
“Earthquakes per se are not dangerous, it’s how buildings are constructed and the quake’s timing that cause deaths,” said Boschi. “The Bam quake happened in the morning when people were all still in bed, unconscious and defenseless.”
Stavros Joannides, a Cypriot structural engineer who worked in Iran in the 1970s, said mud bricks were not flexible enough.
“Once that elasticity is lost and there is no steel, no reinforced concrete, the building will give,” he said. “Without warning. Mud brick doesn’t start dropping bits of plaster or brick like a concrete house will. It comes down at once.”
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Posted by: noble on January 02, 2004 at 07:59:40