Literally miles of pile will be installed in New Orleans over the next two years as the U.S. Army Corps of Engineers rushes to bring the area’s flood-control system to 100-year protection levels by June 1, 2011. As the largest civil-works project in the area’s history, it could be a very loud job. But so far it isn’t, thanks in part to a quiet hydraulic machine that area engineers are making some noise over. Initially, the Giken unit sits on a reaction stand. Later, it works atop existing pilings and uses them as counterweight. After driving a piling, the rig�s
Arch dams, classically curved monoliths situated in narrow valleys, are not as common as other types of dams, such as embankment dams and gravity dams. ENR takes a look at some of the biggest arch dams in the world, both completed and under construction.