Concrete work operations administered within the erection of monolithic concrete and ferroconcrete structures and installations made from cement concrete. Concrete work includes the subsequent basic processes: preparation of the concrete mix; delivery of the combination to the development site; feeding, distribution, and compaction of the combination within the formwork (molds); the curing of the concrete while it's hardening; and internal control of the concrete work. By 1975 the quantity of concrete work administered within the USSR within the construction of commercial buildings, public buildings, and other installations made from monolithic concrete and ferroconcrete will reach approximately 150–160 million cu m per annum . In heavy hydroengineering projects, the quantity of concrete poured amounts to 5–7 million cu m. internal control of the concrete work includes making concrete samples at the work site, maintaining them under conditions on the brink of those of production, and testing the samples for strength. When special requirements for the concrete are involved , the samples are tested for impermeability to water, resistance to freezing, and other factors. so as to see the density and strength of the concrete, the sclerometric, ultrasonic, and radioisotopic methods of testing, all of which are nondestructive, are used. additionally to the present testing, checks are regularly conducted on the conformity to engineering specifications of the standard of the materials utilized in the concrete, the exactness of the batching, the right preparation of the structural components for concreting, the right procedures in pouring the concrete, the observation of proper time periods for removal of forms, and so on.