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The paper considers the efficiency of using self-stressed concrete as a core for steel-concrete columns square section. On the first step the bearing capacity for steel-concrete column square section 100 × 100 × 3 mm length 500 mm with concrete C16/20 as the core was obtained. At the next stage we determine which cross-section is necessary to obtain the same bearing capacity when using self-stressed concrete as a core. To determinate bearing capacity of steel-concrete columns the unified method for polygon steel-concrete columns was used. For self-stressed concrete, the prismatic strength of concrete should be replaced with the reduced prismatic strength, taking into account the compressive stresses of concrete in the process of self-stressing and volumetric compressing. The minimum required concrete self-stress ensures the concrete core and steel shell collaboration . To ensure the collaboration the Poisson ratios of the self-stress concrete and steel shell should be equal. This is necessary for optimal design of the construction which takes in account, among other parameters, the consumption of self-stress cement. The same bearing capacity with using self-stressed concrete will be provided with cross section 80x80x3 mm, length 500 mm. A verification was performed for the section 80x80x3 mm. Bearing capacity for regular concrete was 440 kN and 435 kN for self-stressed concrete. The concrete composition to produce self-stress concrete with specified characteristics was selected. Portland cement M400, river sand, crushed stone fraction 5-10, Alumina cement and gypsum were used as components for concrete mix. To obtain the Sp-1.2 self-stress grade the consumption of the self-stress cement was chosen. As a result, the cost of a column with self-stressed concrete is less than the cost of a column with regular concrete by 20.6 %, the weight of the column decreased by 8.67 %, the cross-sectional area decreased by 36 %.

How do we understand the armed conflict in Eastern Ukraine and what are its implications for Ukraine’s domestic politics as well as for stability in the region? The media, policymakers, and political analysts have used several competing narratives to explain the armed conflict in Eastern Ukraine. This paper examines three competing narratives of the armed conflict. The first narrative focuses on domestic causes of the conflict; the second narrative examines the role of Russia in the insurgency; and the third narrative describes the conflict as a result of Western policies and interference.

A new constructive design of a bridge column pier, which is a load-bearing component of bridges and overpasses as well as of complex multilevel interchanges underlying a transport infrastructure, is proposed. The design is based on a steel mesh casing that is made from a solid-web plate by means of cutting meshes and further expansion of the solid-web plate using non-waste technology. Experimental research data on the bearing capacity and deformability of the cylindrical steel-concrete load bearing components of bridge column piers are provided. They are compared with research data on load bearing components having a solid casing. To make the experimental picture complete, analogous research data on cylindrical concrete load bearing components are provided. This experiment includes static and low-cycle loadings of samples under axial compression mentioned above. On the basis of the information obtained, the effort and travel fields are formed, the critical forces of structure buckling are determined. The analysis of the rationality of the cylindrical steel-concrete load bearing component of bridge column piers is carried out, using the experimental research data. To verify the research data, which are obtained in the course of the study of the critical forces of cylindrical steel-concrete load bearing component buckling, the experimental results are compared with theoretical ones.

Determination of critical load values of eccentrically loaded columns was subject of studies by such authors as Vatulia G. L., Galagurya E. I., Glazunov Y. V., Zhakin I. A., Opanasenko E. V., Storozhenko L. I., Timoshenko S. P., Trull B. A., Hoff N. D., Chikhladze E. D. and other researchers. However, those works have not studied properly work of statically determinable and statically indeterminable columns, compressed eccentrically at one end and being under the axial compression at the other one. The article deals with the problem of determining the critical load for the following design patterns: a column that is loaded at the ends by longitudinal forces by equal and single-direction eccentricities; a column that is rigidly clamped at the bottom, hinged at the top and loaded by longitudinal force at the upper end eccentrically; column rigidly clamped at the bottom, loaded at the free end of the longitudinal force eccentrically; a hinged column, loaded at the upper end of the longitudinal force eccentrically. Critical load of excentrically loaded columns with different types of bearing and load patterns can be determined using the obtained equations. Allowable deflection value according to the regulatory documents and geometric characteristics of the considered columns should be specified to solve these equations.

This study examines the mechanisms through which the ruling party won a plurality of votes using a combination of legal changes and manipulative practices during the 2012 parliamentary election in Ukraine. Legal changes in electoral rules—the replacement of proportional representation to a mixed system—helped the ruling party weaken the opposition parties. These changes enabled the ruling party to engage in manipulation and fraud during campaigning and on election day by suppressing competition, crowding out the races with “technical” parties and “clone” candidates, and manipulating the composition of electoral commissions. The change of electoral system also enabled outright fraud on election day. A combination of these techniques disrupted both the contestation and participation dimensions of democracy, effectively pushing Ukraine into a state of competitive authoritarianism.

The authors proposed the results of fire resistance evaluation of steel-concrete beams with external sheet reinforcement at standard temperature range of fire in the room and justified specifications for flame-retardant coat due to design standards. In order to analyze fire resistance the three-dimensional computer models were developed taking into account the basic conditions of beams loading and bearing as well as non-linear "stress-strain" dependencies of concrete and external reinforcement.

The use of various types of plastic lubricants (such as LZ-TsNII, ZhRO, etc.) in the axle boxes of locomotives, cars and track machines in the Ukrainian railway network causes technological inconveniences at the stage of procurement, supply and regulation of this process, moreover, their operational capabilities do not quite satisfy modern operating conditions of axle boxes of the railway rolling stock. The paper proposes to solve this problem by using a single brand of modern multi-purpose lubricant on lithium complex basis (k-Li) – MZT – in axle boxes of all types of railway rolling stock. The presented results of the comparative analysis of the physical and chemical properties of the mentioned lubricants demonstrate that the MZT lubricant completely meets the operating conditions of the axle bearings and can provide their high-quality lubrication under any conditions of operation. The tribological studies of lubricants on frictional testing machines, with simulation of their operation with rolling friction and sliding friction, demonstrated that anti-wear, antifriction and anti-cuffing properties of the MZT lubricant are much better than those of LZ-TsNII and ZhRO lubricants. It has been found out that the properties of the MZT lubricant are most effectively used under high load in friction pairs. The paper presents the results of testing the MZT lubricant in the actual conditions of operation of locomotives, railway cars and multiple unit rolling stock, which demonstrated its high efficiency and operation capacity.

One of the most important factors determining the reliability and safety of operation of the continuous welded rail track is the temperature of the rails. All conditions of laying, repair and maintenance of the track during the entire cycle of rails operation depend on it. The existing rail temperature monitoring method does not take into account a few significant factors and that leads to significant errors in determining the actual temperature of the rail bar. The authors propose a new rail temperature measurement method on a special test bench which maximally simulates possible environmental operating conditions for the rail bars, the profile of the roadway (embankment or cut), as well as the actual spatial latitude and meridian location of the rail slabs. At the bench, the studied rails are fastened with the help of rail braces on half ties, in the ballast bed, with sizes in accordance with the existing reference documents. At the first stage, the most common KB-65 intermediate fastener for the continuous welded rail in Ukraine will be used, while in subsequent stages KPP-5 fastening will be used.

This paper reviews Ukraine’s 2012 parliamentary election. Despite political repressions and significant disadvantages in access to media, the opposition parties won a majority of the proportional representation seats. However, the Party of Regions maintained its parliamentary majority by winning more than half of the single-member districts and luring independent candidates into the ruling coalition. Two new parties that cleared the electoral threshold – UDAR and Svoboda – joined Batkivschyna in their opposition against the incumbent government. The post-election developments indicate that the parliamentary majority established by the Party of Regions is quite unstable and the presence of radical right and radical left parties will make the new parliament highly confrontational.