Yevgen Gorokhov, Volodymyr Mushchanov
About state of normative basis in the building area in Ukraine. Problems and perspectives of the development
Donbas National Academy of Civil Engineering and Architecture
Abstract.In the article the general approach to the formation of normative basis in Ukraine on present-day stage, which determined by creation of two combining function system: national, which process the basis of before worked out engineering tradition, and European, harmonized with normative documents of European Union. The general witting about focus area, carried out by working party which was created according to the order number 471 dated 19.09.2012 of the Ministry of regional development, building and housing and utilities services of Ukraine, about deposition of professionals of DonNACEA to the realization of problems of regulatory system creation for both designing scheme, development of training principals and retraining of professionals on the basis of establishment of international cooperation all over considering directions have been given. The key information about content of developmental textbook to the normative documents of Kazakhstan by professionals, harmonized with the orders of normative basis of European Union has been given.
Keywords: design norms, Eurocodes, textbook on designing, training and retraining of professionals.
Volodymyr Vasylev, Yevgeny Shevchenko, Anton Tanasoglo, Andrei Alyokhin
Study of spatial operation of the lattice cross components in full-scale tests of an optl support on the testing ground of DonNACEA
Donbas National Academy of Civil Engineering and Architecture
Abstract. There is given a design procedure of definition of central displacements of metal dead-end supports of overhead power transmission lines (OPTL) in full-scale tests on the testing ground of tests of overhead power lines and tower structures of the Donbas National Academy of Civil Engineering and Architecture (the Testing ground of DonNACEA). There is analyzed a mode of deformation of an OPTL support U220-2+9 which is considered as a spatial multiple indeterminate open system with flexible joints. There is given design data of central displacements of working and non-working support faces in the software package «SCAD». In definition of central displacements there is analyzed a joint operation of the lattice components of an OPTL support, supporting influence of the stretched lattice diagonal element members is taken into account. On the base of received results there was thoroughly compared the experimental values of central displacements of the second panel from below and the ones specified in the software package «SCAD». The given technique enables to define the central displacements not only for OPTL supports but also for the antenna supports and open switching centres to check the deformability of construction in normal and emergency operating modes.
Keywords:overhead power transmission line, testing ground, test, experimental unit, metal support, design loads.
Anatoliy Yugov, Alexey Bondarev
Stress-strain state of metal single layer cylindrical covering shell of as a result of erection errors
Donbas National Academy of Civil Engineering and Architecture
Abstract.In the article the stress-strain state of single layer cylindrical covering shell due to possible errors in construction has been it is investigated. The results of numerical analysis and static analysis of shells on the perception of mounting loads – the assembly effort have been given. The obtained values of the stresses in the shell element indicate the need for structural measures that will reduce the impact of the assembly stresses on the bearing capacity of the shell. Method of estimation of the possible errors in the erection of the stress-strain state of the cylindrical coating shell given in the paper can be used in the design of real single layer cylindrical shells, spherical, elliptical, conical, toroidal, and other forms.
Keywords: spatial-span metal covering, mounting stress, stress-strain state, FEM, assembly errors.
Ivan Peleshko, Zinoviy Blikharskyy, Igor Baluk
Formation of design schemas and determination of the stress-strain state of steel structures in the process of reconstruction and reinforcement
National University «Lviv Politechnique»
Abstract. The formalized method of presenting design schemes of steel structures subject to reconstruction and reinforcement by changing the structural scheme and regulation efforts in the «redundant» linkages is proposed. To determine the stress-strain state structure with regard to changes in the design scheme during the process of reconstruction proposed to form and solve a matrix system of equations finite element method with multiple right parts for the basic design scheme. This scheme includes current, deleted, new rods and linkages imposed or liquidated during the reconstruction and reinforcement. Forces in structure is propose to determine as the sum of force in the basic design scheme of external loads and linear combination of forces from units of loads in the «redundant» linkages of the scheme. The input of basic design scheme and process of reconstruction in program optimization OptCAD are described.
Keywords: steel structures, reconstruction, reinforcement, rod system, the design scheme, the stress-strain state.
Volodymyr Vasylev, Yulia Dozorenko
Manufacturing designs perforated beams with guaranteed distribution diagrams of the internal stresses in steel manufacturing plants
Donbas National Academy of Civil Engineering and Architecture
Abstract.This article is devoted to the production of beams with a perforated wall. The technology of production of perforated beams, excluding editing tee beam elements before assembly. Particular attention is paid to the influence of temperature on heating the internal stresses and their redistribution schemes of the dissolution profile of the rolling on a workpiece by means of gas burners, shows a schematic block-diagram of the «dissolution». The theoretical diagrams of internal stress at all stages of manufacture and the resulting internal stresses in the diagram of the perforated beam after fabrication. This work aims to further study the stress state of perforated beams, taking into account the proposed technology of their manufacture.
Keywords:perforated, stress, plastic deformation, dissolution, zig-zag cut, beam hardness, residual stresses.
Ieva Misiunaite, Algirdas Juozapaitis, Tomas Merkevicius
Improvements on the structural response control of unconventional cable-stayed bridges by nonlinear analysis modelling
Vilnius Gediminas Technical University
Abstract.An unusual cablestayed bridgewiththe cable stays placed below the deck and having polygonal layout due to deviation by means of struts is named under-deck cable-stayed (UDCS) bridge. UDCS bridges usually have significant nonlinear behaviour due to direct anchoring of cablestaying system into the deck. These nonlinearities mostly depend on dimensionless slenderness parameter. Designing UDCS structures for the better cross-sections utilization the prestressing of cable stays is widely used. This paper presents a new perspective for structural response control by means of eccentric anchoring of cable-staying system. Numerical examples emphasises the efficiency of the proposed computational technique. Moreover, the comparison analysis carried out considering structural behaviour of the UDCS structure both as linear and nonlinear. On the basis of such comparative studies, several conclusions are drawn concerning the safety and accuracy of the structural behaviour estimates yielded by nonlinear analysis and, in particular, when accounting for all initial imperfections.
Keywords:UDCS bridge, nonlinear analysis, imperfections, structural response control, rational eccentricity, rational moment, generalized imperfections factor, simple-span system, beam-column.