Copyright 1981 Newsweek
LENGTH: 708 words

HEADLINE: What Happened at the Hyatt?



Flags flew at half mast throughout Kansas City last week, and funeral processions wound through the streets. Outside the Hyatt Regency Hotel, where 111 people died in the collapse of two aerial walkways two weeks ago, "No Trespassing" signs barred the curious and the morbid. Inside, a fine dust covered the floor, and a few balloons clung wanly to the ceiling. But the wreckage was gone, trucked to a nearby warehouse, and the sole remaining "sky bridge" had been dismantled. With investigators arriving daily and lawyers lining up to file suits, the city was beginning to come to grips with a tragedy that may not have ended yet: 81 victims still lay in hospitals, 8 of them on the critical list.

The biggest question--how a year-old structure could fail so spectacularly--remained unanswered. Investigators said it might be a year before they knew the precise cause. One reason for the delay was that the hotel's owner, Crown Center Redevelopment Corp., a subsidiary of Hallmark Cards, Inc., began restricting access to the debris: its own investigators got first crack, while others representing the Hyatt Corp., the architects and various victims' attorneys waited in line. After the first few days, "the door pretty much slammed shut," complained Michael J. Davies, editor of The Kansas City Star and Times, which are conducting independent investigations. Crown Center promised eventual cooperation, but, said Bemard Ross, president of Failure Analysis Associates, a firm retained by the hotel's architects, "We're stymied. . . Whether they altruistically give up parts and pieces for examinations in our labs without court orders remains to be seen."

In the absence of facts, theories abound. An early favorite is that one or both of the walkways buckled from "harmonic" vibrations set up by people swaying or dancing, each wavelike motion reinforcing the one before until the stress became too violent for the structures to endure. But witnesses disagree on whether there was dancing on either walkway; moreover, says Roger McCarthy of Failure Analysis, there are telltale signs in the skeleton of a structure well before it suffers vibration failure. "I haven't seen the hallmarks of that here," he says. Another theory is that the walkways were overwhelmed by sheer weight; Hyatt president Patrick Foley, however, says that they were designed to hold "wall-to-wall people"--more than were on them at the time.

"Double Stress': Wayne G. Lischka, a structural engineer hired by the Kansas City Star, has discovered a design change that "would result in double stress" on the fourth-floor walkway's steel box beams. Originally, six steel rods were to be run from the ceiling through the upper bridge to the lower one on the second floor. But the actual construction used twelve rods, six suspending the top bridge from the ceiling, the other six hanging the lower bridge from the upper. The result: the fourth-floor bridge was subjected to increased loads from two directions. While declining to say that this could have caused the collapse, Lischka does call it "significant." Other investigators say that two of the washers intended to spread out the stress where the rods met the beams appeared to be missing, and there is some suspicion that they had never been installed.

There also are questions about the credibility of the investigations. While Mayor Richard Berkley has asked the National Bureau of Standards for help on the case, most other investigators represent people with interests at stake. And there is skepticism about Crown Center's conduct, especially after records of the Occupational Safety and Health Administration revealed that during construction a large section of the lobby roof had caved in. This was discovered only because OSHA inspectors were at the site to look into an unrelated accident. Then there is the removal of the remaining walkway, for both safety and legal reasons. Noting that it would have been useful to test the structure in place, Berkley says that the move, coming as it did in the middle of the night, "doesn't give a very good impression." A city with a reputation for community cooperation suddenly seems at odds with itself even as it struggles to live with its sorrow.

GRAPHIC: Picture, A welder cuts down the last lobby walkway: A score of investigators were waiting in the wings, AP