Report on Coliseum Says Further Study of Damage Is Needed : Reconstruction: Completion of repairs depends on inspection of structural components and monitoring of continuing aftershocks, according to engineers. A hearing is set for Monday.

An engineer’s and architect’s report released Friday on earthquake damage at the Los Angeles Memorial Coliseum is filled with qualifications and said further structural examinations would be necessary to ascertain the total damage to the historic facility.

Nowhere in six pages of written comment did structural engineer Nabih Youssef and architect Terry K. Miller state unequivocally that the Coliseum is repairable.

Instead, they said: “We are confident that within the parameters established in this report that repairs will provide a facility that meets applicable seismic and life safety requirements to once again operate as a public assembly facility.”

The key phrase is “within the parameters,” meaning that completion of repairs would be dependent on exposure of vital stadium components for further inspection as well as monitoring of continuing aftershocks.

Even before receiving the report, Coliseum Commission President Yvonne Brathwaite Burke had called the Coliseum Commission into a special session Monday afternoon to consider the next steps. Burke, chairwoman of the Los Angeles County Board of Supervisors, had no immediate comment on the report.

The commission’s vice president, City Council President John Ferraro, said Youssef and Miller will be invited Monday to explain matters further. “I can see why they want to be a bit evasive because they’re not positive of some of the interior (stadium) elements deep down,” Ferraro said.

Coliseum official Don C. Webb said the possibility of reopening the stadium in time for the fall football season by the Coliseum’s main tenants, the Raiders and USC, will have to be evaluated after further engineering and architectural reports. He added that the time is short and the commission must act quickly to begin repair work.

On Wednesday, the Los Angeles City Council voted to allocate an initial $10.9 million in federal disaster funds received by the city to start work at the Coliseum.

In their concluding paragraph, Youssef and Miller said it was “impossible to accurately determine the total costs associated with rehabilitation of the Coliseum without the full inspection and testing results as described above.”

“However, our review of the preliminary estimate (of repair costs) as developed (by Webb) supports the possible cost of $33 million for repairs,” they added.

“Refinement of the costs will occur as solutions are developed for rehabilitation. A detailed work plan must be created in order to determine the priorities of the work effort.”

Youssef and Miller cautioned that the Coliseum “continues to receive aftershocks and subsequent damage can be anticipated.”

“This report is preliminary in the determination of rehabilitation efforts required to stabilize the existing structural components and facility systems,” they said. “Continued analysis will identify necessary repairs to ensure the facility meets code requirements for operation as a public assembly facility.

“The initial tasks of stabilizing the structural frame is necessary in order to conduct further visual and dynamic inspection of the affected areas,” Youssef and Miller said.

“In addition, the suspect areas of the stadium as described above must be uncovered in order to fully assess damages in areas not visually accessible,” they said.

They also recommended these immediate steps or policies:

* “The building should not be occupied for normal uses until repairs are completed. Inspectors and workmen should take precautions to avoid (areas that) have been serious damaged.

* Columns, beams and arches with major damage should be shored immediately to prevent additional damage.

* “The exterior . . . should be exposed to identify areas of structural damage. In areas where movement of the building has loosened concrete and is susceptible to falling, the concrete should be removed immediately to mitigate potential falling hazards.

* “In order to monitor damage levels and safety of the facility during continuing aftershocks, we recommend that some instrumentation be provided to measure earthquake movements. . . . This is especially critical for seriously damaged structural columns and beams.”

As for damage in specific parts of the 71-year-old stadium, Youssef and Miller said:

“The concrete slab of the upper concourse appears to have incurred significant cracks and displacement around the entire length of the stadium.

“The upper seating bowl has been displaced four to five inches above the lower seating bowl on the north side . . . and to a lesser degree on the south side.

“The structural integrity of the peristyle is the primary concern in our observation of cracking that occurred at the top and center of the arches supporting the scoreboards as well as the vertical and horizontal cracks observed in the main arch.”

Destructive Forces

The Jan. 17 earthquake caused severe damage to the Los Angeles Coliseum, raising questions about whether the historic stadium could be repaired or would have to be demolished. A structural engineer’s assessment Friday repoeted that the Coliseum is possible repairable, but said more testing is needed to determine exact repair costs. The Coliseum Commission will meet Monday to consider the report.

1. Seating separation and uplift

Significant cracking and upheaval ranging from one to five inches occurred between rows 50 and 58 throughout much of the lower bowl. The majority of the access tunnels also suffered cracking.

2. Cracked and subsided slabs

Significant cracks and displacement of the concrete slab occurred on the upper concourse from one to three inches around the entire length of the stadium.

3. Cracked Columns

About five concrete columns (A) experienced major shear damage and many more (A and B) experienced flexural cracking.

Exterior (B) columns appear to have pulled away from the bowl and tilted slightly outward.

4. Fractured beams

Several steel-reinforced concrete beams were seriously damaged with vertical cracking the full depth of the beam.

Stadium utility systems

Although testing has not ben done, many utilities including power and gas rate suspect. It is highly probable that more testing will find that the systems must be replaced.

Damaged peristyle: Significant damage has occurred with cracks appearing to penetrate the full depth of the structure near the scoreboards.

Sources: Don C. Webb, Coliseum project director; preliminary report by Terry K. Miller and Nabih Youssef.