Experts Say Danger to Structures Was Known

The collapse of the Nimitz Freeway in Oakland, the partial failure of the San Francisco Bay Bridge and the severe damage to buildings in San Francisco’s Marina district have aroused more indignation than surprise among a number of seismic experts around the state.

“There were no real surprises . . . no new lessons there, not from this earthquake, none at all,” said Peter Yanev, chairman of EQE Engineering Inc. of San Francisco, a large earthquake engineering consulting firm.

Yanev is one of several engineers interviewed Wednesday who said that state transportation officials have known for years that roads and bridges such as the Nimitz Freeway and the Bay Bridge, built before the 1971 Sylmar earthquake, were not as strong as they should be.

“That we have known these things for years and had no concerted push to do something is tragic,” Yanev said after viewing much of the devastation in the Bay Area on Wednesday.

State officials have said that some repairs had been made on the Nimitz and that others--which would have strengthened the columns and joints that appear to have failed--were part of a planned second phase of repair work.

Fred Turner, a staff structural engineer for the California Seismic Safety Commission, on Wednesday described the Nimitz as “nonductile concrete, a well-known type of hazardous construction.”

Tim Tobin, a spokesman for the commission, said it will to take at least five years to replace the overpass section of the Nimitz that collapsed. This will be “a major, major disruption in traffic patterns and highway infrastructure. There will be a fairly significant number of lawsuits in terms of culpability. I’m not trying to paint it too bleak; I’m taking a realistic look at everything. This is another grim reminder of the lessons we should have learned from Mexico City and Whittier. This only confirms what we’ve already known.”

After surveying the damage in San Francisco, Tobin said: “When I see this, it’s terribly sad. I stood on a street corner in Armenia during the quake at a school site where 600 kids died, and all you could have done was cried. I get very angry when I see the damage in San Francisco. The government and engineers just have not done what needs to be done. What does it have to take? California has got to face this earthquake problem.”

At a meeting of the state Transportation Commission in Sacramento on Wednesday, Commissioner Stanley W. Hullett predicted that the Bay Area’s “economy is going to come to a standstill” because of the highway problems triggered by the earthquake.

“It’s well known we have no money left in the pot with which to build highways, much less fix these highways,” Hullett said. “We’re going to be in difficult straits in order to be able to find the money,” he said.

About $110 million in federal money has been spent in California in the past 15 years as part of a project to seismically strengthen the state’s bridges and highways, according to David W. Frederickson, a spokesman for the U.S. Department of Transportation in Washington.

Frederickson said another $64 million has been earmarked for a second phase.

Frank Baron, a retired professor of civil engineering at UC Berkeley, where he taught for 29 years, said that the number of studies on structural failure following the Sylmar earthquake gave officials the wherewithal to make necessary repairs on older highways and bridges in the state.

“They (state officials) have had sufficient knowledge from the studies to do the remedial retrofitting to ensure that severe damage did not occur.

“The lesson that San Fernando (Sylmar) taught us was very important. We were not giving enough strength to the piers (columns) of certain freeways, nor sufficient support to the decks,” said Vitelmo Bertero, director of the earthquake engineering research center at Berkeley.

Bertero is heading a team of structural engineers assigned to survey damage and prepare a report for the Earthquake Engineering Research Institute in El Cerrito.

After examining the Nimitz Freeway on Wednesday, Bertero said it was clear that the piers lacked crucial lateral reinforcement.

“There are probably no new lessons to be learned from this earthquake. It just re-emphasizes the old lessons that we haven’t paid attention to,” Bertero said.

As for San Francisco’s Marina District, a well-to-do neighborhood built on soft soil, Bertero said: “I have been preaching for a long time against building on filled land. If it (the area) is rebuilt, it should be done only on special foundations that are very expensive.”

John Kariotis, a structural engineer known nationally for his work on seismic safety, said Wednesday that he was not surprised by the collapse of the Nimitz Freeway. Nearly all elevated Caltrans structures built before 1980 lack sufficient support in their columns, he said, and could be too brittle to withstand major earthquakes.

“All these kinds of elevated structures are damned vulnerable,” he said.

The problem in Oakland was exacerbated by the landfill on which the roadway is built, he said. The similar double-decked Embarcadero Freeway on the San Francisco side of the bay appeared to have weathered the quake without a collapse because it is on more solid ground, he said.

Kariotis recommended that all such pillars be wrapped with extra steel supports and then coated with another layer of concrete. “The technology does exist,” he said. “It’s simply a matter of money.”

He estimated that the retrofitting would cost billions of dollars but that taxpayers frightened by the collapse will now be willing to approve bond measures for such work.

“I have a suspicion this is going to help people understand you can’t just build something and say ‘this is going to last forever,’ ” he said.

However, Kariotis stressed that there is nothing inherently dangerous with the concept of double-decked roads, like the one proposed over portions of the Harbor Freeway, if they are built to new standards.

He is director of that group and has been active in revising building codes for earthquake areas. Kariotis, who runs a firm headquartered in South Pasadena, is scheduled to travel to San Francisco today to inspect buildings for clients.

The 1971 earthquake centered in Sylmar taught Caltrans the need to reinforce the connections between elevated spans of roadway, according to Kariotis. Subsequent quake experience and research should have alerted officials to the possible weakness of the columns under elevated roads and bridges, he said. Yet, the state did not do enough on that, he said.

“You can only cry wolf so much,” he said.

Times staff writers Larry Gordon in Los Angeles, Douglas Frantz and Sam Fulwood III in Washington, Ed Iwata in San Francisco and Mark Gladstone in Sacramento contributed to this story.