CSUN Garage Collapse Fuels Tougher Policy

Acting on lessons learned from the Jan. 17 earthquake, state university officials announced a tougher construction policy Tuesday for parking garages like the one that collapsed at Cal State Northridge and ordered a new seismic review of buildings at all campuses.

The new garage standards represent the first time the system has adopted a seismic policy that exceeds the state building code, according to Jon Regnier, Cal State’s director of physical planning and development.

Officials of the 20-campus California State University system said the new standards were spurred by the failure of the nearly new, $11.3-million garage on the Northridge campus.

During a committee meeting of the Cal State Board of Trustees, officials said future garages will be required to have shear walls--wooden or concrete bracing used to stiffen and strengthen buildings against lateral heaving--and more steel reinforcing in vertical columns.

A $4.1-million, 660-space garage planned for Cal State Chico that lacked shear walls is being redesigned to include them.

The 2,500-space Northridge garage that was heavily damaged in the Jan. 17 quake had neither shear walls nor the extra steel reinforcing in its interior vertical columns. Cal State officials said that building codes did not require them.

The builder, A. T. Curd Builders of Glendale, did not return calls Tuesday.

“We’re quite prepared as a board to go beyond the code at this time,” said Charles Thiel, chairman of the university system’s Seismic Review Board, a panel of seven seismic safety experts convened in mid-1992 to review university buildings and seismic policies.

Citing the collapse of Parking Structure C at Northridge, review board member Ted Zsutty said, “This is a case where we learned something and we want to make sure we don’t have a recurrence of that problem.”

Structural engineers have long said buildings with shear walls generally are more resistant to earthquake damage. But Regnier acknowledged there has been resistance to using the walls in garages in the past because they make the buildings less open, and can cause security and ventilation problems.

“Without the experience of the collapse at Northridge, we wouldn’t have had too much of a leg to stand on” in recommending the change, said Zsutty, a former San Jose State civil engineering professor, and the seismic board member who reviewed the plans for the Chico garage.

Plans call for the Chico garage to be poured-in-place cement construction, unlike the assembly of precast segments used to construct the collapsed CSUN garage completed in mid-1991, Zsutty said. By comparison, another CSUN garage that survived with little damage had shear walls and was poured in place.

Thiel said the policy will remain in effect until the state updates its building code to reflect lessons learned from the quake. But officials said the Chico garage is the only such project pending.

Thiel is also heading a group of experts looking into the causes of the Northridge garage failure on behalf of the university system. He said that panel expects to forward its report in about two months. After Tuesday’s meeting, he explained in general how the building appears to have failed.

Thiel said some interior support columns--which held up giant concrete floor slabs--failed in the quake. The weight of the floor slabs pulled the stronger exterior walls inward, causing the outside columns to bend inward.

The Times disclosed Feb. 11 that engineers hired by the university system had warned earlier that the Northridge garage did not meet seismic safety standards. But construction went ahead under the original plans after Cal State and Curd officials reviewed the warning.

During the next several months, members of the Seismic Review Board also will reinspect other campuses to re-evaluate buildings, paying extra attention to steel-frame and recently constructed buildings that suffered more quake damage than expected.

One example is the wings of the Delmar T. Oviatt Library at the Northridge campus, which were heavily damaged in the quake despite having been built recently. The original library, built more than 20 years ago, suffered less damage.

Thiel said the new review, expected to take several months, may result in more Cal State buildings being added to a list of 100 seismically suspect buildings that officials released in fall of 1992. The university system plans to start retrofitting the first group of them this year.

Although CSUN officials are still tallying the damage, unofficial estimates have put the campus’ earthquake loss at up to $350 million, which would make it the costliest disaster ever for a U. S. university. Officials have said the recovery process at CSUN could take several years.

The garage, known as Parking Structure C, was the only facility on campus to partially collapse. But most major classroom and office buildings, built in the late 1950s and 1960s, were closed initially due to earthquake damage or resulting fires, chemical spills and asbestos contamination.

Quake damage delayed the start of classes by two weeks to mid-February.