Defending a coveted spot from fierce competition is almost harder than reaching that position in the first place. It’s a scenario that engineers of the 2011 Ford Super Duty pickup truck know well. Slide Show Photo: Thom Blackett / ENR An optional, electronic-locking rear differential helps the 2011 Ford Super Duty get out of tight spots. As it turns out, that kind of pressure is a good thing, especially for heavy-duty pickup-truck buyers who want to tow more than 20,000 lb, strap in 3 tons of payload and spend less money at the pump. As ENR also discovered during a
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.