But above all else, the question was not would Rem Koolhaas and Ole Scheeren’s 522-foot tower be rebuilt, but could it even be done? The Office for Metropolitan Architecture and Mandarin Oriental declined to comment, pending a full investigation. Meanwhile, the project’s engineer, Arup, released the following statement: “Until the full facts emerge, we can’t speculate on the causes of the fire or the extent of damage.” Fortunately, engineers not involved in the project were willing to shed some light on the science and history of fires in highrise structural steel buildings.
First off, the taller the building and the higher the fire, the better: taller structures have more steel to dissipate damaging heat, and a higher fire means less load to destabilize steel columns. “Think of it as a ten-pound steel box versus a one-pound steel box,” said Borys Hayda, managing principal at DeSimone. “The more massive element needs ten times as much heat put into it to reach the same temperature as the smaller one.”
And while it might seem that OMA’s gravity-defying structures could render them prone to collapse, Hayda said that in the case of fire, complexity helps, because it typically means more structural members are available to provide redundancy. It also helps that the building is a hotel, which means shorter spans—more rooms—and thus more columns and heat dispersion. Another factor in keeping the temperature below the critical 400-500 degree threshold is “blow out.” “If windows start breaking, there’s a way for the heat to get out, and it can be fine,” said Andrew Mueller-Lust, principal at Severud Associates. Photos of TVCC showed most every window blown out.
As to historical precedents for reuse, Mueller-Lust and others pointed to One Meridian Plaza, a Philadelphia office tower stricken by a fire on the 22nd floor in 1991. The fire raged for 18 hours, burning out one floor before moving on to the next, until it ran out of fuel at the 38th floor. Testing showed that the building could have been restored, but no one was willing to reoccupy it. It stood for years before finally being razed.
The same fate may await TVCC. “As I read the Chinese newspapers, according to the official statements, the main structure is very little damaged,” said Tian-Fang Jing, principal at Weidlinger Associates. While that might be the case, the greater issue remains whether anyone would willingly go into a repaired TVCC.
And if the building is structurally sound, reinforcement may be warranted. “If you’re forced to add so many columns that the space becomes economically unfeasible, that’s no good,” Hayda said. “And if you need to reinforce the elevator core, and the elevators won’t fit, or the stairs are no longer wide enough, that just can’t be done.” He added that TVCC could turn out to be cheaper to repair than replace. But before that is even an option, those doing the number-crunching are going to be engineers—and not accountants—to make the most important call.”