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The combined experimental and theoretical approach was applied to the study of high-speed deformation and fracture of the 1810 stainless steel. The material tests were performed using a split Hopkinson pressure bar to determine dynamic stress-strain curves, strain rate histories, plastic properties and fracture in the strain rate range of 102 ÷ 104 s-1. A scheme has been realized for obtaining a direct tensile load in the SHPB, using a tubular striker and a gas gun of a simple design. The parameters of the Johnson-Cook material model were identified using the experimental results obtained. Using a series of verification experiments under various types of stress-strain state, the degree of reliability of the identified mathematical model of the behavior of the material studied was determined.

A study of the strength and deformation properties of freshwater ice under compression, tension and shear in a wide range of strain rates (10−4 − 3 ⋅ 103 s−1 ) and temperatures of − 5∘ C, − 20∘ C, − 40∘ C and − 60∘ C was performed. Static stress-strain curves of ice under compression were obtained on which the identified strength properties of ice as well as compressive modulus. To determine the mechanical properties of ice at high-speed loading the Kolsky method was used with various embodiments of split Hopkinson bar. The deformation curves were obtained at various loading conditions. Thereon breaking points were defined as well as their dependence on the strain rate and temperature. Also static and dynamic strength properties of ice at splitting and circular shear were defined. Increase in the dynamic strength properties upon the static ones for all loading conditions was marked.

The results of dynamic tests of two refractory materials based on zirconium dioxide: three types of ceramics and barium-aluminate concrete. The ceramic specimens had various initial density and porosity and also differed by technology of manufacturing. Compression tests were carried out using the Kolsky technique and its updating - specimen in a rigid jacket. The dynamic stress-strain curves were obtained. The strong influence of sample's initial grain composition, mode of stressed-strained state and technologies of manufacturing of specimens onto ceramics mechanical properties is marked. In the event of a serious accident in a nuclear reactor with its core melting, it becomes crucial to prevent the propagation of the resulting radioactive flux into the en- vironment. The problem of confining the melting core is vital for all the countries using nuclear power plant. A corium trap material is anticipated to undergo an influence of various factors, such as mechanic and thermal shocks resulting after falling the melt and the structural elements into the trap, a vapor explosion resulting from the contact of the melt with water, chemical interaction with corium, and a radiation effect. The anticipated high temperature of corium (2800-3000K) and its chemical activity in oxidizing conditions considerably reduce the choice of materials that could be used for the trap. The currently developed corium trap based on using the highly refractory dioxide zirconium concrete has to increase the life of a protecting trap by two orders of mag- nitude as compared to the construction concrete. However, use of the cements with the melting temperatures of 2300 K and lower in the above concrete reduces the merits of the refractory component - zirconium dioxide. The dioxide zirconium-based sintered ceramics is free from the above drawbacks. To assess the potential of using dioxide zirconium ceramics, comparative studies of dynamic strength of the ceramics and of some highly refractory concretes under high-velocity loading are to be conducted. The aim of the paper is to analyze experimentally the influence of the loading rate on the strength properties of dioxide- zirconium ceramics and concrete based on zirconium aluminate.