San Diego's outdoor earthquake simulator — the world's largest — got a workout Tuesday morning. Researchers were measuring how long metal pilings might help boost a building's ability to withstand a major quake.
The platform moaned as it replicated the shaking and sliding of a magnitude 8.9 earthquake.
A 50-foot-tall metal box sat on the center of the shake table. It was filled with tons of sand. At the top, two heavy cubes stood in for buildings. They rested on 7- to 12-foot long thick metal pilings. Those metal spikes absorbed and then diminished the force of the quake coming from the table.
A host of sensors and cameras recorded and measured the test structure during the simulated temblor. Researchers are gathering information that could be crucial for future building standards.
"And when we have the data we can place them into the codes and have engineers understand how these piles react during all different types of earthquakes and different types of buildings. So it will become routine to design buildings safer from the start. Or if they're not built safely, they can go back and be retrofitted," said Amy Cerato, a University of Oklahoma researcher.
Cerato built much of the structure and the pilings in Oklahoma and had them shipped to San Diego. The pilings passed the eye test Tuesday, but she said the real gold will be dug out of the data.
Joel Conte, a structural engineering professor at the Jacobs School of Engineering, said it is important to be able to do tests like this in the real world.
"Even the best simulation tools now, we do not have enough confidence in them to use them systematically to design structures," Conte said.
The outdoor table allows researchers to build taller structures than they could at an indoor facility, according to Conte.
