New product announcements: 11/25/2009 Balance the Load: Spread-Axle Trailer The Equalizer is a nitrogen-assisted dampening system now integrated into Talbert 55SA and 60SA spread-axle heavy-load trailers. The system is able to hydraulically transfer loads in all terrain conditions. It provides proportional weight distribution for each axle grouping to reduce stress on loads. Talbert Manufacturing, Inc.; 800-348-5232; www.talbertmfg.com Getting Down: Controlled-Descent Rescue Device The Miller SafEscape ELITE Rescue/Descent Device is a controlled-descent device that is rated for one or two users at a time. Designed for use in rescue situations from elevated heights, with custom-designed kits for wind-energy and tower-crane applications.
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.