Exposed architectural concrete for walls and roof defined the headquarters of the American Concrete Institute in Detroit. Designed by architect Minoru Yamasaki and built by Pulte-Strang, Ferndale, Mich., the concrete roof is a folded plate that cantilevers off the central corridor. ACI has since moved headquarters to a new building in Farmington Hills, Mich.

Take a look at other significant projects over the past fifty years in which concrete and industry innovations played a major role.