Quake aftershocks include charges of shoddy building. Following Armenia's devastating earthquake, Soviet officials have begun making charges of construction code violations. But given the country's economic straits and urgent need for new housing, it is unclear how sophisticated the Soviets can afford to be in rebuilding.

Mihran Agbabian remembers well his discussions with building designers when he visited Armenia two years ago. ``Their design codes are similar to ours'' in earthquake-prone areas, says Professor Agbabian, head of the civil engineering department at the University of Southern California and himself of Armenian descent.

``But when I saw how their buildings were actually constructed, I felt sick.... Their designers said they were also concerned, but that a different ministry, the Ministry of Construction, was in charge of getting the right materials and supervising the quality of construction. The majority of people in that ministry were not knowledgeable, the designers said.''

A week after Armenia's devastating earthquake, the litany of complaints about Soviet earthquake-zone construction is well-known: The concrete was too weak. Steel reinforcements were either too light or nonexistent. The joints linking prefabricated components, a common type of construction in a country trying to cope with a housing shortage, were insufficient. (Relief efforts expand to rural areas, Page 9.)

Surveying the damage Monday, Prime Minister Nikolai Ryzhkov told reporters: ``We believe gross violations were permitted'' in building construction. The Communist Party daily Pravda called for the prosecution of the ``scrap-builders'' who constructed the buildings, which became ``concrete and metal graves.'' Incompetence may not be the only crime. There have also been allegations of possible corruption. Builders may have syphoned off materials for personal use or sale, a problem throughout Soviet industry.

American seismologists and earthquake engineers caution against too much criticism. ``This was, after all, a 700-year earthquake,'' says Walt Hayes of the United States Geological Survey.

The Soviets had been expecting a quake in that region some time over the next six years, but no one predicted the Richter-scale magnitude of 6.9 that occurred. In addition, the earthquake was shallow and its epicenter was right near populated areas, causing an intensity level of nine or 10 out of a possible 12, Mr. Hayes adds.

There is no such thing as a fully earthquake-proof building. According to a 1987 study funded by the National Science Foundation, if an earthquake of similar intensity were to hit Los Angeles, 20,000 buildings would be damaged.

Still, two stark facts point to human negligence in Armenia: Every building with more than five stories fell, according to Leonid Bibin, deputy chairman of the State Construction Committee. And more old buildings survived the quake than new.

The Mexico City earthquake of 1985, which had intensity levels similar to those in Armenia, also provides some unflattering comparisons. Though the Mexican death toll is thought to have been several times the official number of 4,200, it was nowhere near the Armenian level of 50,000-60,000.

The reason is simple. ``The Mexican buildings were built better,'' says Bob Kidder, director of the National Center for Earthquake Engineering Research in Buffalo, N.Y.

Even as relief and rescue operations continue, the Soviets have begun to look ahead to reconstruction. According to Prime Minister Ryzhkov, no new buildings in the quake area will be taller than three or four stories. The Soviets have also indicated that they will allow teams of earthquake engineering experts from around the world to assist Soviet experts in the planning - something they didn't do after the earthquake that leveled Tashkent in 1966. (Already, the United States and Soviet Union have been sharing earthquake research data as part of a science and technology exchange begun in the 1970s.)

But given the Soviets' economic straits and the urgent need for new housing - 500,000 Armenians are now homeless - it is unclear how sophisticated the Soviets can afford to be in their reconstruction.

There are two basic methods for making a building quake-resistant. One way is to make the structure so stiff that if the ground moves, the building moves as one solid unit. The other technique, for use with high-rises, is to make the entire building flexible, through the use of flexible steel joints and giant steel and rubber shock-absorber-like structures at the base of the building.

The earthquake engineers interviewed did not show much enthusiasm for putting up more prefabricated housing. Little research has been done into how to make prefab buildings more earthquake-resistant, they say.

``There's not a lot of professional confidence in prefabricated building,'' says Charles Scawthorn, a structural engineer at EQE Engineering in San Francisco. ``The details of connections between beams and columns are critical. If they're not done properly, they fail.''

Given the Soviets' limited resources, experts suggest the Soviets set priorities for which buildings get the most earthquake fortification, such as hospitals and other municipal centers.

John Tomblin, chief of the prevention and support services branch at the UN Disaster and Relief Organization in Geneva, says that medical services should not all be built in one part of a city. That way when a tremor hits, there is at least a possibility that some health facilities will still be standing.