Yevgen Gorokhov, Volodymyr Vasylev, Igor Garanzha, Olexandr Leshchenko
The perspective directions of increase overhead power lines performance efficiency in Ukraine
Donbas National Academy of Civil Engineering and Architecture
Abstract.In article perspective directions of scientific researches and the engineering offers, aimed at increase efficiency performance of overhead power lines (OHL) by pressure 6–330 kV are described. In Ukraine their necessity has sharply arisen for last years, in connection with the occurred cascade troubles on OHL 330 kV in territory of Crimea autonomic republic, when on the foreground there were questions of reliability, working life of lines and uninterrupted operation of supply electricity to consumers. This article are based on perfection techniques of definition climatic loads (ice-wind), and also working out new and updating of existing constructive decisions OHL supports with application progressive materials. In this case the creation composite supports on the steel polygonal poles basis, which already approved in practice with filling by self-condensed concrete are meant. Besides, the working out so-called «anti-trouble supports», allowing to exclude cascade destructions on OHL become more and more necessary. The questions of increase throughput, optimization and adaptation overhead lines to European building standards Euro code are synopsized.
Keywords: overhead power lines, climatic loads, steel polygonal poles, composite supports, anti-trouble supports, many chains OHL.
Anatoliy Yugov, Alexey Bondarev
Static calculation single layer cylindrical rod metal shells of covering
Donbas National Academy of Civil Engineering and Architecture
Abstract.Investigation of stress-strain state of single layer shell of coating when exposed to the design load combinations under the conditions of static loading have been in the article represented. The results of numerical static calculation of shells on the perception of operating loads have been analysed. The values of the stresses in the cell membrane, and the main traverse shell coating show the need for structural measures that will increase the stiffness of the shell. Constructive activities for exploring single layer metal shell of covering, which will increase its rigidity to the required according to DSTU B V.1.2-3:2006 figures have been suggested. Constructive solution of the shell given in the paper can be used to develop single-layer shells of cylindrical, spherical, elliptical, conical, toroidal, and other structural forms.
Keywords: spatial-span metal coating, rod barrel shell, loads, stressstrain state, FEM.
Ioury Martynov, Vitali Nadolski
Serviceability limit states associated with the web buckling due to shear stresses
Belarusian National Technical University
Abstract.The interaction of some cases ultimate limit state with the serviceability limit states is established. Thereby the single and multiple local buckling of the web are considered as serviceability limit state for checking shear resistance according to Euro code 3 «Design of steel structures». The method for checking shear resistance with the aforementioned serviceability limit state is developed and the sphere of application of these checking is proved. A general procedure for determining the necessity of the serviceability limit states associated with the loss of local stability is described. The necessity of the serviceability limit states in determining the shear resistance of steel elements is analyzed. It is shown that the limit state of serviceability, the corresponding local buckling of the web due to shear stresses can be reached before the ultimate limit state. The conclusions of the necessity of the further researching into the improvement of the engineering design method of shear resistance.
Keywords: shear resistance, serviceability limit state, web buckling, web post buckling work, resistance models.
Oleksander Golodnov, Victor Psyuk, Boris Ivanov
Predictable alignment of steel structures by welding
Donbas National Academy of Civil Engineering and Architecture,Poltava National Technical Yu.Kondratyuk University
Abstract.Subject matter of article is solution of actual problem which is possibility of alignment of structures in operation by welding. Change of residual stress state of structure after overlaying of welding joints is predicted by calculations. In process of evaluation of reinforced elements deflected mode are accepted standard hypotheses such as smallness of lateral deformations influence assumption and flat sections hypothesis. Experimental research of work of elements reinforced under load helped to define that deviations from linear law of deformations distribution are found in zones which are directly adjacent to welding joints. Small length of mentioned zones in comparison with section dimensions allows usage of flat section hypotheses in practical calculations. Special feature of reinforced elements calculations is need for modeling reinforcement technology because it significantly influences on reinforced structures work. Numerical calculations help to receive solutions for particular tasks only by specified parameters of system, initial and limit conditions of system and particular work execution technology.
Keywords: operation of structures, residual deflection, alignment by welding, prediction of residual stress state, technology.
Sergey Pichugin, Anton Makhinko
To formulation of generalised wind;excited model on tall slender structures
Poltava National Technical Yu.Kondratyuk University, Building Company «ETUAL»
Abstract.In this paper one of possible generalised wind-excited model on tall slender structures is formulated. Base of model is schematization of atmospheric turbulence as two uncorrelated stochastic process: along wind and lateral wind turbulence components. It is shown that account of lateral turbulence component for tall slender structures with aerodynamic asymmetry form leads to an essential increase of their crosswind response. The model is formulated on the basis of long-term experiences of dynamic design of slender tall buildings in the various probabilistic technic. The material is stated regardless to design schemes of building structures and stochastic wind loads. In practical calculations it is offered to operate with simple mathematical models with dimensionless parameters.
Keywords: atmospheric turbulence, wind turbulence, stochastic process, tall buildings, aerodynamic asymmetry.
Volodymyr Vasylev, Natalia Agbash, Aleksey Karabanov
The management of one bolting elements of the lattice with a belt in the supports of power transmission lines
Donbas National Academy of Civil Engineering and Architecture
Abstract.The article describes the mechanical testing of prototypes is one of bolted connections, which indicated the existence of stock carrying capacity with minimal regulatory distance from the center of the hole to the edge of the edge of the roll angle 1,2d. The analysis of the normals used in the design of bolted connections, which showed that there are different approaches in their nomination. The article discusses the reduction of the distance from the center of the hole to the edge of the edge of the roll angle of up to 1,2 d 1,0 d, which significantly increases the gauge diameter bolts, and allows you to reach full strength of the lattice support trunk and node connections. In this paper we defined a rational width of the belt in one bolted from the condition statement of the maximum diameter of the bolt.
Keywords: elements of transmission towers, one bolted connections, the maximum diameter of the hole, the normal carrying capacity of bolted connections.
Viteliy Sirobaba, Alexander Novitskyy, Karen Zorabyan
The management of one bolting elements of the lattice with a belt in the supports of power transmission lines
Sumy Building College, Sumy National Agrarian University
Abstract.The paper presents calculations for metal frames of single-storey quick-assembling building, manufactured from light steel thin-walled structures and roll-formed section. The results of comparative analysis have been carried out. Bundled software «LIRA 9.6» was used for structural calculations. Design model of building frame was designed. Section of light steel thin-walled joist web «C» (sigma) and box type joist web was constructed with the help of program «LIRA-KTC». The model was calculated with two types of joist web and rated force for both types of joist web were determined. Specific quantity of metal was defined for the two types of joist web. According to analysis the rated force which take place have been made. Cost of metal was estimated without taking into consideration carrying cost, corrosion protection and assemblage. As a result optimum alternative was found and it’s efficiency was proved.
Keywords: light steel thin-walled structures, roll-formed section, software suite «LIRA», quick assembling buildings.