Photo courtesy of Blue World Crete Green concrete startup has developed a cement that forms at low temperatures. MaterialsA Florida company's new geopolymer binder, which promises to enable eco-friendly materials that compete with portland cement, is undergoing testing in the U.S. and the Middle East.Blue World Crete, whose eponymously named firm is based in Pompano Beach, Fla., is one of many ongoing efforts to lower concrete's carbon footprint. Even so, experts are skeptical it can offer an alternative to the world's most popular building material: portland cement.The startup claims to have developed a synthetic alternative to traditional cement. Inorganic chemicals
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.