Photo courtesy of Optech Inc. A mobile mapper equipped with a lidar kit can scan infrastructure at highway speeds. Image courtesy of HNTB Corp. A lidar point-cloud diagram shows engineers where roads, bridges and all the surrounding "street furniture" is located. Related Links: At FIATECH, Mapping Tool for Buried Utilities Generates View From Three Sensors (requires login) Surveying roads and bridges used to take weeks of on-the-ground work, but now it is as easy as going for a drive."We can do in a matter of hours or a day what would take months with traditional survey," says Paul DiGiacobbe, associate
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.