Seismologists use SF skyscraper to study quakes

SAN FRANCISCO

The glistening glass and white concrete are the epitome of modern. But what's underneath exists because of what happened more than a century ago.

"If you were standing right here on Rincon Hill in 1906, you would've seen a city in rubble," California Department of Conservation Director Mark Nechodom said.

That great earthquake began a movement in engineering to design a building meant to stand up to violent shaking.

One Rincon Hill is one such building.

"The One Rincon Hill building has one of the most structurally advanced designs of any building in the United States," California Geological Survey spokesperson John Parrish said.

Sitting in a concrete box, and reinforced by a metal substructure, the tower is an early example of what's called performance-based engineering. Tucked away in corners and closets and connected by two and a half miles of cable, accelerometers will silently measure the shaking whenever an earthquake occurs.

"The system is up and running, and already taking the building's pulse," Parrish said.

The sensors are mounted in boxes, each with two accelerometers -- one for vertical movement and one for horizontal movement.

"It shows that at the roof, it's moving about nearly one thousandth of an inch, so you can see that's really high precision information we're getting," California Geological Survey spokesperson Tony Shakal said.

There are 72 accelerometers, placed at different corners, on different floors of the 64-story building. They will let scientists create a 3-D model of exactly how the building sways and flexes during a major seismic event.

"In an earthquake, actually the building will have S-like motion and then you need more sensors to track that S-like motion," Parrish said.

That data will advance the science of building skyscrapers.

Copyright © 2024 KGO-TV. All Rights Reserved.