Moving from the lab to the field, a highway off-ramp bridge under construction in Seattle features memory-retaining metal rods and bendable concrete designed to provide the structure with flexibility sufficient to withstand a major seismic event.
Currently under construction in downtown Seattle, the Washington State Dept. of Transportation project uses 15 years of research from Dr. Saiid Saiidi of the Earthquake Engineering Lab at the University of Nevada, Reno, to build a bridge with columns able to return to their original shape after an earthquake as strong as magnitude-7.5.
Because it can moderate the damaging effects of earthquakes, base-isolation is a technique used primarily in seismically active regions. ENR takes a look at some of the largest applications of base-isolation technologies in the world.