THE STUDY AUGUST 24, 2011
Fair enough: Yesterday’s earthquake, as The Washington Post notes, “was not a killer quake, nor even a particularly injurious one.” And maybe the hyperventilating initial reaction out here on the East Coast deserved the snarky jabs of anonymous twittering West-Coasters. But if you’ve never experienced it before, there is something decidedly unsettling about feeling a normally-stagnant building shake and rattle while you’re working inside it. (Here at TNR, the office chatter quickly morphed from “Does anyone else feel that?” to “The whole building is shaking!,” followed by a rush to the stairwell. Then came an hour of standing around outside. That, along with everyone’s shock at the earthquake, revealed us as Washingtonians: There was a palpable impatience to get back to work instead of enjoying the sunny, pleasant afternoon.)
The overall impact was slight, though the quake didn’t spare some of the capital’s most treasured landmarks: Union Station, the National Cathedral, and the Washington Monument were all damaged. These are massive stone and marble structures. Shouldn’t they have been able to withstand the quake?
Not necessarily. To be earthquake-resistant, it’s important for buildings to be flexible as well as strong—and height simply adds more risk. According to this earthquake fact sheet from Penn State University, tall structures are more vulnerable, because as the ground at their foundation accelerates during an earthquake, their height amplifies “the motions of longer period motions when compared with small buildings,” and they shake for longer periods of time. An earthquake guide provided by the College of Charleston concurs and adds this point: “The taller a building is,” it explains, “the more the top of the building moves relative to the bottom of the building.” (Sure enough, the damage sustained to the Washington Monument was at the top.) Crews are now evaluating these landmarks to determine how they will be repaired.
And as for a landmark close to our readers’ hearts—TNR headquarters—don’t worry: Although the quake did result in a cracked wall in one corner of the office, we emerged otherwise unscathed.