Officials Examine Disturbing Quake Repair Data

The failure of quake repair methods for steel-frame buildings prompted concerns and questions Monday for city officials and building owners faced with the repair of broken beams and joints on dozens of Los Angeles high-rises.

Tests by the University of Texas at Austin cast serious doubt on the effectiveness of retrofitting recommended by the Los Angeles Department of Building and Safety, causing city officials and high-rise owners to wonder aloud how to proceed with repairs to quake-damaged steel-frame buildings.

Geoff Ely, executive director of the Building Owners and Managers Assn., representing about 1,500 members throughout Los Angeles County, called a Times report Monday of the tests “disturbing.”

But Ely said he cannot gauge the impact to building owners until more information about the tests is released. “This only indicates to us that this issue is more complicated than we originally estimated,” he said.

Ely and city officials hoped to get some questions answered at a meeting late Monday between city building officials and representatives of the American Institute of Steel Construction, which ordered the tests. The meeting at a convention of the institute was closed to the public and news media.

The test results and other information are expected to be released at a news conference today. (Tuesday).

Steel-frame office buildings, designed to bend with the forces of an earthquake, were considered among the safest in riding out a temblor. But after the Northridge quake, building experts were shocked to find cracking on welded connections of beams and columns of at least 90 buildings, mostly in the San Fernando Valley and on the Westside.

Results of the Texas study--the main effort to find a solution to the problem--disturb experts because the welding methods and design changes tested are currently being used to make repairs to quake-damaged high-rises and in new construction.

The Los Angeles City Council voted in May to draft an ordinance that would require the owners of steel-frame buildings to inspect the buildings for damage within three months of notification by the city. Repairs, using the methods questioned by the Texas tests, would have to be completed within one year after they are recommended by inspectors, under the proposed ordinance.

Richard Holguin, assistant chief of the city’s building bureau and head of a city panel that studied quake damage to steel-frame buildings, said, “it’s still too early to tell” what the tests will mean to the city’s recommended repair program.

But if the tests are accurate, Holguin said, the “repairs that are being recommended do not appear to provide a permanent correction.”

Wilfred Iwan, ,chairman of the California Seismic Safety Commission, said he had not received any information on the Texas tests and is eager to have more information so the commission can complete a set of changes to the state’s building codes requested by Gov. Pete Wilson after the Jan. 17 quake.

“I think it’s important for that report to get out,” he said.

When Iwan read The Times report on the tests Monday, he said many questions came to his mind about how the tests were conducted and what recommendations will be made as a result.

“Clearly there is a potential for a huge problem,” he said. “What it may be saying is you have to be careful of quick solutions.”

The Texas test used life-sized columns and horizontal beams that were welded together in California and shipped to the University of Texas, where a hydraulic arm was used to shake the beam, simulating a quake.

After the steel frames were strengthened with plates and welds, some connections nonetheless broke after the beams had been shaken up and down just once.

Greig Smith, chief of staff for Councilman Hal Bernson, who recommended the inspection and repair program for the city, said he had not heard of the Texas tests and could not comment on the results. But he added that there is still time to amend the city repair program to include whatever recommendations city building officials make as a result of the tests.

The city’s repair recommendations to the owners of steel-frame buildings were based on engineering simulations conducted before the temblor. These showed that joints reinforced in certain ways, usually with steel plates, performed better than those built to the current code.

City officials said owners of about 30 steel-frame buildings have taken out permits to make repairs, and about half of the repairs have been completed.

Ely, of the building owners association, could not say how many steel-frame buildings within his group have begun the repair work recommended by the city. But he added that whatever repairs are under way probably will be completed regardless of the test findings.

“The repairs under way provide more public safety than not having any repairs,” he said.