One recent Sunday afternoon while he was biking in New York City's Central Park, Theodore Zoli's cell phone rang. It was a call from James Ray, a U.S. Army Corps of Engineers senior researcher with the Engineering Research and Development Center in Biloxi, Miss. Troops in Afghanistan were concerned about a bridge that had been damaged by fire. Could they safely cross it?
Ray hated to interrupt the notoriously busy Zoli on a rare day off, but he urgently needed an answer. Ray knew he had to call HNTB Corp.'s national chief bridge engineer, known for his work in making structures more resistant to blasts and fires—whether from accidents, terrorism or enemy fire.
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.