EarthquakesWorld's Largest Outdoor Earthquake Simulator Undergoes Major Upgrade
A major upgrade to the world’s largest outdoor earthquake simulator reached a milestone mid-April when the facility’s floor—all 300,000 lbs of it—was put back into place. When completed this fall, the simulator will have the ability to reproduce multi-dimensional earthquake motions with unprecedented accuracy to make structures and their residents safer during strong shakes.
A major upgrade to the world’s largest outdoor earthquake simulator reached a milestone mid-April when the facility’s floor—all 300,000 lbs of it--was put back into place. When completed this fall, the simulator will have the ability to reproduce multi-dimensional earthquake motions with unprecedented accuracy to make structures and their residents safer during strong shakes.
The simulator, or shake table, will be able to test the world’s heaviest and tallest structures to gauge how well they would withstand various types of earthquakes. The shake table will be equipped with the ability to reproduce all the six possible movements of the ground, known as six degrees of freedom. The first test following the upgrade will feature a full-scale, 10-story, cross-laminated timber building.
“This facility will save a large number of human lives by making the places we live and work in safer during earthquakes,” said Joel Conte, the shake table’s principal investigator and a professor of structural engineering at the University of California San Diego. Conte and colleagues lay out the details of the upgrade in a paper published in January 2021 in Frontiers in Built Environment.
In the paper, researchers also detail the impact that the shake table has had on building and design codes since it opened in 2004.
In San Francisco, approximately 6,000 “soft-story” wood-frame buildings are being retrofitted to make them safer in strong earthquakes. Full-scale testing of retrofit systems for these soft-story wood-frame buildings was performed on the UC San Diego shake table in 2013. Professor John van de Lindt from Colorado State University, who led this project, played a key role in writing the guidelines for the retrofit of these buildings.
In 2008, a test led by Professors Robert Fleischman of the University of Arizona and Jose Restrepo of UC San Diego led to new recommendations on how precast concrete floors, known as diaphragms, should be built into parking garage structures to improve their seismic behavior.
