Photo courtesy of Las Vegas Paving Corp. Despite its age, giant drill Big Stan (in yellow) is booked up in the Southwest. Las Vegas is crowded with performers, but few are as huge as Big Stan. Thought to be the world's largest truck-mounted drill, Big Stan is flexing its muscles south of the Strip on a $252.5-million, 7-mile-long widening of Interstate 15.Big Stan's tall stance originally sprang from deep roots. The 250,000-lb, 93-ft-high boring behemoth was built in 1986 by Anderson Drilling, Lakeside, Calif., now a part of London-based Keller Group PLC. The mega-machine, which cost $1.5 million to construct,
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.