Teams of budding and seasoned architects faced off last week for the second annual Iron Designer Challenge, where they constructed freestanding “Portals”—structures that mediate two spaces—in less than three hours. Photo Laura Mirviss The Gensler team after winning the 2011 Iron Designer Challenge. Photo Laura Mirviss The Turner team assembles their Portal, which is primarily made out of bamboo. Related Links: Architects, Students Compete in Iron Designer Challenge Student Teams Strive to Build Best Emergency Shelter The Gensler team won the 2010 contest, in which participants built emergency shelters, and once again, it took home the grand prize. Inspired by
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.