Compared with some of its Manhattan neighbors, a high-rise on the corner of Seventh Avenue and West 47th Street looks standard. Like many buildings in Times Square, the 41-story retail-entertainment-hotel development, nearly topped out, has a tower springing from a boxy base that will sport a flashy billboard.
Though the $1-billion development, called 20 Times Square, involved mining 30,000 cu yd of bedrock, 20 TS’s excavation was not as nerve-racking—or claustrophobic—as carving a concert “cave” under the landmarked Carnegie Hall, 10 blocks north. That project, which finished a year late in December 2002, was dubbed Carnegie Hell (ENR 7/16/01 p. 30).
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.