Sources: U.S. Geological Survey; CP staff
The U.S. Geological Survey has developed the first map of rock deposits exhibiting the potential to contain or form pyrrhotite, whose presence in otherwise ASTM C33 aggregate can prove extraordinarily deleterious in concrete. The map is part of a new fact sheet, “Pyrrhotite Distribution in the Conterminous United States,” whose publication abides a Congressional directive addressing widespread residential foundation failure cases in Connecticut and Massachusetts.
Sources: Charah Solutions Inc., Louisville, Ky.; CP staff
A Southeastern utility has tapped Charah Solutions for a Closure by Removal impoundment project encompassing upward of 100 acres of ash deposits at a coal-fired power station that was retired in 2015. Work will include installation of environmental controls plus rail infrastructure improvements and extension, along with loadout area construction. Over a multi-year contract, Charah anticipates processing of 2 million-plus tons of impounded material for beneficial use as concrete-grade fly ash, while preparing the former pond acreage to be restored as usable property.
Source: Quikrete Companies, Atlanta
Quikrete and California-based Contour Crafting Corp. have entered into a collaboration to develop proprietary concrete used in the automated construction of residential, commercial, industrial and government structures using the latter’s technology. Following comprehensive testing at an independent accredited lab at the University of Southern California to confirm ICC-ES AC509 compliance—a building code spearheaded by CC Corp.—the 3D printing process will be used to construct four low-income housing units as part of a demonstration project sponsored by the Los Angeles County Development Authority.