Participants in some of New York City’s largest concrete construction projects are now trying to determine the potential impact of the Feb. 17 conviction of the city’s main concrete testing firm and its owner for filing false test reports. A state supreme court jury in Manhattan rules that Testwell Laboratories and its owner, V. Reddy Kancharla, were guilty of the flawed fillings related to concrete strength on more than 100 projects that used the firm’s services. They included the Freedom Tower at Ground Zero and the Second Avenue subway. The jury has yet to rule on other charges against Kancharla,
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.