Trailblazers seeking a faster, safer and less costly way to build concrete shear walls in seismic-zone high-rises have pioneered the use of steel fibers as link-beam reinforcing-steel "decongestants." Having smoothed the path and proven the concept on a limited basis in a 24-story tower in Seattle, the builders of The Martin Apartments say they are eager to use the approach on a broader scale.
"This unties the Gordian knot in seismic link beams, which have [bedeviled] contractors for years," says Cary Kopczynski, the force behind the rebar decongestants and president of the Bellevue, Wash.-based structural engineer that bears his name.
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.