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Prospects of application of roller compacted concrete in hydro schemes of Ukraine are considered. The number of dams erected with application of roller compacted concrete is growing year after year in the world. Roller compacted concrete is an especially dry concrete mixture with decreased content of cement and increased content of pozzolana (fly ash). The broad physico-mechanical peculiarities of roller compacted concrete depend not only on its composition but also on technology of its laying and compacting in dam. Rapid construction of gravity dams with use of equipment for earth-moving works enables the more economic construction of protective embankments. Prospects of application of roller compacted concrete during erection and restoration of existing protective embankments in regions with increased flood hazard in the west of Ukraine are considered. The use of roller compacted concrete allows reducing construction deadlines by a factor of 2–3, and, in so doing, reducing the labor content by a factor of 4–5 at the expense of full mechanization of works. Decrease in content of binder in composition of roller compacted concrete by 30–80 kg/m3 favors decrease in heat release and, correspondingly, the occurrence of temperature contraction cracks, which in its turn favors economy during construction of hydro-technical structures of hydro schemes.

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When performing calculations to assess reliability of hydraulic structures of cascades of hydroschemes on the basis of probabilistic methods, the necessity to simulate random natural-climatic phenomena producing loads and effects on hydraulic structures arises. In particular, statistical series of random quantities of such important natural-climatic phenomena are considered: annual lowest average monthly temperatures, annual maximal amplitudes of average monthly temperatures. Each of the enumerated natural-climatic phenomena is characterized by presence of close correlation connections between random quantities when passing from one hydroscheme of the cascade to another. The necessity to consider correlation connections requires construction (simulation) of joint distribution law of random quantities system. The purpose of the work is simulation of joint distribution law of system of random variables that do not satisfy the normal distributions, taking into account correlation connections between random variables when passing from one hydroscheme of the cascade to another. Methods of the theory of correlation and methods of mathematical statistics with the use of software package MathCad were used in the course of the investigation. Simulation of joint law of distribution of system of random variables that do not satisfy normal distributions, taking into account correlation connections between random variables when passing from one hydroscheme of the cascade to another, and also assessment of accuracy of results, that were performed, have shown advantages of this approach from the viewpoint of accuracy of results obtained by different procedures. The results can be used in probabilistic calculations of reliability of hydraulic structures and cascades of hydroschemes.