New York City’s skyscrapers are built to withstand most earthquakes
NEW YORK — The ground rumbled Friday beneath New York City, home to famous skyscrapers like the Empire State Building and One World Trade Center. Though buildings that can reach above 100 stories might seem especially vulnerable to earthquakes, engineering experts say skyscrapers are built with enough flexibility to withstand moderate shaking.
The 4.8 magnitude quake on Friday morning was centered about 45 miles (72 kilometers) west of the city in New Jersey. New York Gov. Kathy Hochul said Saturday there had since been at least 25 aftershocks, some of which were felt in New York City. But no major damage had been reported to the city’s roads, mass transit system or its 1.1 million buildings.
Operators of the iconic 103-floor Empire State Building posted “I AM FINE” on Friday on the building’s X account.
New York’s skyscrapers have been generally built to withstand winds and other impacts far greater than the earthquakes generally seen on the East Coast, said Elisabeth Malsch, a managing principal at Thornton Tomasetti, a New York engineering firm that’s done major work on the Empire State Building, Chrysler Building and the Brooklyn Bridge, among other major city landmarks.
“The earthquake that we design for is one that’s unlikely to happen. It’s a thousand-year event,” she explained. “So we don’t expect it to happen more than once in a thousand years.”
Skyscrapers, by design, are less susceptible to the ground-shaking action of earthquakes than shorter structures because they’re made to sway ever so slowly and slightly to protect themselves against powerful, hurricane force winds, Malsch said.
“Taller buildings just are more flexible because they’re designed for the push and pull from the wind, which has a bigger effect on tall buildings than the push and pull of an earthquake does,” she explained.
Even the oldest skyscrapers are, by necessity, made of high strength concrete and steel to withstand the gravitational load on the massive structures, added Ahmad Rahimian, an executive vice president at the engineering firm WSP Global.
“High-rise buildings can be one of the safest places you can be in an earthquake,” he said.
