IMMERSED STEEL TUBE TUNNELS - AN AMERICAN EXPERIENCE

The idea of immersing a prefabricated tube tunnel was first put into p ractice in the United States in 1896, for a water line crossing Boston Harbor. Over the past century, immersed tube technology has continued to evolve in the U.S. After introducing and discussing advantages and disadvantages of immersed tube tunnels, the paper describes the devel opment of basic advances in the design and construction of immersed tu be tunnels within the last 60 years in the United States. Design and c onstruction features of selected major projects also are described.