Related Links: Imagining Construction's Future “I’m getting too old for this,” or so goes the daily ritual at the start of every shift. Since the normal 24-hour cycle is meaningless here, that happens once every 18 hours. I think the 18-hour day was developed by the US Navy for use on submarines. Oh, for the days back on Earth—24-hour days; wake up and get a cup of coffee and go out on the patio and soak in a little sunshine! Things are not that way now. It’s a chemical sponge bath, put on an ill-fitting plastic jumpsuit, and off to
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.