Products 04/06/2011 Way Down In The Hole: Drill Rig The Sandvik DI550 is a down-the-hole hammer drill rig that features a 434-hp diesel engine and a 24.4-m³ compressor with airflow at 24 bar. It is designed to work with Sandvik’s 3-in. to 5-in. RH550 hammers. The rig features a built-in dust collector with persistent cleaning to reduce overall dust emissions. Sandvik Mining and Construction; www.sandvik.com Concrete Testing: Portable Field Unit Resipod is a non-destructive, portable device for checking the electrical resistivity of concrete. It meets AASHTO’s TP9511 standard on concrete surface resistivity. Proceq; 800-839-7016; www.proceq.com Concrete Bonding: Hot Melt System
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.