The complex fabrication of a $24.5-million tubular, webbed helix of red steel has set back the completion date for the Santiago Calatrava-designed footbridge in Calgary from fall 2010 to mid-June 2011. Billed as Calgary’s longest single-span structure at 126 meters—twice as long as the next longest—the Peace Bridge’s helical design keeps supports out of the water, using buried abutments on either side of the riverbank. The 6.2-m-wide bridge, double the width of other pedestrian bridges in the area, will serve 5,000 residents daily by connecting two growing neighborhoods to the city center and light rail. The city of Calgary wanted
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.