CarlsonDonald R. Carlson, 84, a project architect and construction manager who helped build Chicago’s original McCormick Place convention center in the 1950s, died of renal failure on June 26.Carlson designed projects for Chicago-based C.F. Murphy Associates, which later became Murphy/Jahn Architects. He worked on the original $35-million, 320,000-sq-ft McCormick Place that opened in 1960 but burned down in 1967. He also served as architectural production chief during the early 1970s on all terminals, gates and operational facilities for the 13 original airlines at O'Hare International Airport.Carlson later worked for Martin B. Schaffer & Associates, redoing the top four floors of
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.