Tough economic times around the world are taking a toll on global construction spending. Back-to-back annual declines have been reported for the first time in two decades, according to results of an annual survey of 69 construction markets. In its 2009 global construction outlook, IHS Global Insight Construction Services, Lexington, Mass., projects a 3.7% decline in total global spending this year, to $5.6 trillion. This dip would come on top of a 1.2% drop in 2008. The combined figures represent “the steepest decline in global construction spending in at least 20 years,” says Scott Hazelton, the research firm’s director 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.