Back From Devastated Area, Scientists Cite Fundamental Weaknesses : U.S. Team Faults Construction in Armenia Quake Toll

American scientists who toured the shattered cities of Armenia said Wednesday that the catastrophic toll of the Soviet earthquake last month resulted from inadequate seismic designs for apartments, schools and hospitals and from construction practices that would be unacceptable in the West.

Organized by the National Academy of Sciences in cooperation with the Soviet Academy of Sciences, the U.S. research team said that the fundamental weaknesses found in Armenian construction are likely to exist across the breadth of the Soviet earthquake zone, a 1,000-mile swath of Central Asia and the Caucasus Mountains with a population numbering in the tens of millions.

At a briefing in Washington on Wednesday, three leaders of the 18-member team of structural engineers and seismologists also took issue with current estimates of the death toll in the Dec. 7 earthquake. They said that the official Soviet estimate of about 25,000 dead may be only half to a third of the actual toll.

“The early estimates of 60,000 to 80,000 may be reasonable, may turn out to be accurate,” said Frederick Krimgold, an architect and authority on natural disasters at Virginia Polytechnic Institute.

A downward Soviet reassessment of earlier, much higher figures appears to be based on the number of bodies recovered, about 25,000, and local census data, Krimgold said. But he said the census is 10 years out of date, and reliable reports indicate that the local population had been swelled by 100,000 Armenian refugees fleeing communal violence in recent months in neighboring Azerbaijan.

Many Bodies Unrecovered

Also, the sequence of events and Soviet construction methods appear to have produced an unusually high ratio of deaths to injuries and an extraordinarily compact rubble from which many bodies may never be recovered, the scientists said.

U.S. team members, who praised the Soviets for their hospitality and candor in the midst of one of the century’s worst natural disasters, flew from Andrews Air Force Base near Washington on Dec. 19 aboard a Soviet cargo plane and returned late last week.

John Filson, a research scientist with the U.S. Geological Survey, said it has been established that the main shock of the quake struck with a force of magnitude 6.8 to 6.9, only four minutes before school children were scheduled to be sent home for lunch.

Many buildings, Filson said, may only have been weakened by the initial shock. Three minutes later, as thousands of people in apartments and public buildings jammed themselves into stairwells in a vain struggle to escape, a second shock of 5.8 collapsed many of the buildings in Leninakan, Spitak and Kirovakan.

One feature of Soviet construction that contributed to the high death toll, the researchers said, was the use of prefabricated, hollow concrete “planks” to form the floors of high-rise buildings, rather than conventional slabs of reinforced concrete. As buildings tumbled, the concrete “planks” fell like so many logs, forming dense piles of rubble that afforded few pockets of space--and air--for survivors.

In most major earthquakes, Krimgold noted, there are three or four injured for every death. “Here, the ratio was reversed,” he said.

The most important factor, researchers agreed, was poor quality of construction, especially in buildings erected since the 1960s, when pressures mounted to cut corners and conserve steel and concrete, which were scarce.

In a separate interview, Mihran Agbabian, a member of the U.S. team, noted that because Soviet construction ministries build standard apartment complexes in huge numbers, “if you can save 5% or 10% (in materials) the saving is considerable.”

“There is a tendency to cut costs,” said Agbabian, an Armenian-American engineer who heads USC’s civil engineering department. “They are very conscious of the saving of materials and we are not. That is a very important consideration.”

Another peculiarity of Soviet construction, he and other experts noted, is the imperative each ministry feels to meet annual plan quotas, in order to earn pay bonuses, regardless of whether all the necessary cement and steel have been delivered to a project.

“If the steel that should be there does not arrive,” Agbabian said, “they use less of it and move on” to the next project.

A number of collapsed buildings clearly lacked sufficient reinforcing, the researchers said, and many showed signs of unacceptable construction practices. In joining concrete wall panels, for example, steel reinforcing rods did not overlap to provide continuous strength but were in some cases welded end to end.

As a result, Krimgold said, “they came apart the way they went together.”

Gillette reported from Washington and Stein from Los Angeles.