Experts Baffled by Cave-In : Safety: Roof collapse at Long Beach sparks statewide check of campus buildings.

State officials on Tuesday shut down all eight buildings in the Cal State Long Beach music complex where a 120-ton roof collapsed on a concert hall Monday and launched a survey of 19 other state campuses to determine how many similarly built structures exist.

A team of independent experts searched Tuesday in a mountain of debris inside the Gerald R. Daniel Recital Hall for an explanation to the collapse. They said it could be several weeks before the cause is known.

The chancellor’s office that oversees the state university system remained baffled by the cause and was investigating whether some of the system’s 1,200 other buildings might pose a danger. Officials said they had received calls from campuses around the state seeking reassurance that their buildings were sound.

“You just have to be real careful with buildings that house so many students,” said Colleen Bentley-Adler, spokeswoman for the Cal State system. “(But) we have no reports of any problems.”

Tons of concrete and steel thundered onto the empty 210-seat hall where a group of high school students were to have rehearsed just hours before. They were told to leave when faculty members and campus police noticed half-inch cracks and falling plaster.

The music department complex at the north end of the campus was cordoned off and locked until the walls of the concert hall, buckled and bent, could be secured, allowing experts to get inside and analyze the rubble for a clue to what caused the accident, campus President Curtis McCray said.

A team of independent structural engineers and contractors was hired by the state to join the original Long Beach architectural firm of Hugh Gibbs & Donald Gibbs and the Pasadena contracting firm of Shirley Bros. Inc. in investigating the collapse.

Contractor James V. Shirley was at a loss to explain what failed as he surveyed the auditorium now filled with heaps of metal and steel. “I honestly don’t know until I look,” he said.

Campus officials were particularly worried about the structural integrity of two adjacent buildings constructed in the same “tilt-up” style as the hall, where the concrete walls are poured then hoisted into standing position.

“They look reasonably solid, but we just have not had that many problems with buildings” McCray said after touring the complex for more than an hour. “The reason we’re being so damn careful with this is we want to make sure we know what we’re talking about.”

State university officials said they had “no idea” how many of the system’s buildings statewide were constructed in the tilt-up style. Until they know whether the cave-in was the result of a freak accident or a more generic structural flaw, they could not say whether the problem was widespread.

The chancellor’s office was also compiling a list of buildings designed by Gibbs & Gibbs and built by Shirley Bros.

The hall was last inspected Jan. 13 by campus staff, who reported that the roof leaked when it rained but cited no structural damage.

The last known structural inspection of the building was during construction in 1982, and state guidelines require no further structural inspection, Bentley-Adler said.

At least two seismic surveys were made after earthquakes in 1987 and 1989, but no problems were reported, she said.

Some Long Beach faculty members said in interviews that they had been concerned that the complex--constructed at a cost of $6.3 million in 1982--was built “on the cheap.”

“One of our professors predicted the roof would cave in one day,” said Martin Herman, assistant professor of music who was in a nearby building just yards away from the recital hall when it collapsed.

Herman said he was on his way to his office at 10:20 a.m. when he heard three “violent” cracks.

“At first I thought it was an earthquake,” he said. “Everything around me shook violently for a split second. It honestly never occurred to me that the roof had caved in.”

Faculty members said they were annoyed by the leaks that dribbled through the roof even in the slightest rain, damaging musical equipment on several occasions.