Vadim Gubanov
Development of design techniques for high-rise steelworks
Donbas National Academy of Civil Engineering and Architecture
Abstract.The backgrounds to solving problems in calculation, verification and design for high-rise steelworks are discussed in the paper. The analysis of responsibility levels of structural elements and the limit state classification have been done. The schemes of failure sequence have been developed for lattice and shell cylindrical structures. The advice for specification of ways in the high-rise steelworks investigations accounting for changes in structural parameters and maintenance are given. Classification of high-rise structures depending on load-carrying type structures and types of equipment is given. Matching of load-carrying structures functions is the main factor of high-rise structures functioning. The paper deals with the classification of limiting states. It is also established that the limiting state of the first group for the equipment is the limiting state of the second group for the structure as a whole. The analysis of responsibility categories of structures and structure components shows that ranging of components and structures for analysis efficiency increase is possible.
Keywords: high-rise steelworks, reliability, design, maintenance.
Yevgen Gorokhov, Sergey Kuznetsov, Volodymyr Vasylev, Eduard Lozinsky, Andrey Drozdov
Wind load on a high-rise building
Donbas National Academy of Civil Engineering and Architecture
Abstract. In the given work the analysis, operating in the various countries, standard documents and techniques of definition of wind loadings on a high-rise building located in site development is carried out. The optimal technique is revealed. The special attention is given to the methods of definition of aerodynamic factors on surfaces of a high-rise building and to specification of their share in absolute value of wind pressure. Comparison of existing wind tunnels of the closed and direct-flow type is resulted. The wind tunnel project carried out in the Donbas National Academy of Civil Engineering and Architecture, for definition of an estimation of features of an air pressure of a wind which are used for the decision of various technical problems and trial of high-rise constructions is presented.
Keywords: high-rise building, building aerodynamics, wind tunnel, wind effects.
Vladimir Sintsov, Vladimir Mitrofanov, Alexander Sintsov
Stressed-deform state of the transport frame of the ice-resistant steel platform in transit on the work point
National Academy of Environmental Protection and Resort Development
Abstract.Article is devoted to offshore fields. According to the results of state expertise of V. Filanovsky deposit is the largest deposit of oil reserves, discovered in Russia in the last 10 years. In 2013, scheduled to start first with four waterworks, start drilling and put into operation. One of the waterworks is ice-resistant steel platform (LSP). This facility is supporting two steel blocks connected together multi-tiered steel deck. During transportation to the point arrangement to save the configuration jacket platform combined transport frame. Transportation plan to conduct afloat towing at the positive buoyancy of support units, which are metal tanks, reinforced by a system of stringers and ribs and internal hard bulkheads. The paper presents data from studies of stress-strain state (SSS) elements of the transport frame ice-resistant steel platform (LSP), which comprises the supporting blocks during transportation to the installation point. Transport frame and two supporting blocks LPS constitute a single system, such as swimming, «catamaran». Developed a spatial model of the «anchor blocks – transport frame». Investigated the VAT element of the spatial model for the recommended normalized wave loads. The results of numerical studies stress-strain state of elements of the transport frame.
Keywords: оff-shore construction, transport frame, eventual element, method of eventual element, calculation model.
Anatoliy Yugov a, Andrey Myronov a, Oleksiy Bondarev a, Vladimir Moskalenko b
Research of influence of geometric imperfections in farms from roll-formed and welded section by series 1.460.3-23.98 on parameters of the is intense-deformed condition
a Donbas National Academy of Civil Engineering and Architecture
b LTD «Prombudremont Firm»
Abstract. In the article is researched a question about additional efforts in steel farms from roll-formed and welded section (BWF) by series 1.460.3-23.98 on parameters of the is intense-deformed condition. Here are introduced plans examinations farms and results their calculations with consideration of geometrical imperfections. There was given an analysis of takings numerical research and recommendations by reduction value addition efforts in farms from BWF. The obtained values of extra effort and stress indicate that the initial imperfections affect the stress-strain state farms considered series. Results of theoretical calculation can be used during designing or working out of new similar designs from BWF. The account of the considered imperfection at a design stage allows rising in the following operational reliability of the considered designs. It is offered to develop a technique of the account of the basic initial imperfections as a part of universal settlement-graphic program complex Structure Cad.
Keywords: metal constructions, geometrical imperfections, technology of manufacture, MFE, intense-deformed condition, exactitude, numerical design.
Victoria Volkova, Ganna Makarova
The numerical simulation of thin-walled girder deflected mode
Dnepropetrovsk National University of the Railway Transport named after acad. V. Lazaryan
Abstract. In this paper we have investigated the deflected mode of conveyor gallery girders. Three variants of the constructive concept of main conveyor gallery girder were proposed: H-girder, girders with flexible and hard wall. Based on the finite element method, stress and strain fields were derived. Areas of local stresses were identified. In order to reduce local stresses and to ensure local stability of the girder wall, the need to install additional two-side stiffener in zone near the support was shown. The modeling of thin-walled girders was made according to the geometric nonlinearity. The analytical study of thin-walled girder deflected mode was performed according to the «Guidelines for the design of steel thin-walled girders» CSIIProjectsteelconstruction. Comparison of the results with numerical simulations showed a satisfactory agreement. Analysis of thin-walled girder model revealed a significant stock carrying capacity of approximately 20 %.
Keywords: thin-walled girder, deflected mode, finite element method, numerical simulation, stress and strain fields.
Yaroslav Nazim, Olexandr Leshchenko
Method of experimental simulation of icing process on the conductor of overhead lines in climatic chamber
Donbas National Academy of Civil Engineering and Architecture
Abstract. Questions, touching experimental researches of simulation of icing process on the conductor of overhead lines, are considered in the article. For achievement of purpose of researches developed and constructed experimental setting on the base of climatic chamber of laboratory of tests of build constructions and buildings of the DonNACEA. The method of comparative tests of traditional bi-metallic conductors in aluminium and steel is developed with the new types of compacted conductors in a climatic chamber for simulation of icing in a wind stream. It is set that for 5–6th ice districts in accordance with Chapter 2.5 PUE: 2006 a role of torsion of the conductor on intensity of ice load will be substantial, and a difference in weight of ice for the different values of the stiffness in torsion of the conductor can arrive at 25 %. Job performances are needed for further researches, related to the study of the icing on the conductor, and also development of measures with the purpose of providing of accident-free work of OPTL at ice and wind loads.
Keywords: overhead power transmission lines (OPTL), icing, conductor, stiffness in torsion, experimental investigations.
Anton Makhinko
To questions of optimum reliability of building structures
Poltava National Technical University named in honor of Yuri Kondratyuk
Abstract. In this article questions of optimum level reliability of building structures are considered from economic-probabilistic positions and aprioristic risks theory. The model is formulated on the basis of long- term experiences of reliability estimation of steel structures in the various probabilistic technic. In the model are used general laws for structures failure, property of failure curve, structures reliability which is designed on codes. The material is stated regardless to design schemes of structures and stochastic loads. In practical calculations it is offered to operate with simple mathematical models with dimensionless parameters. The social and economic importance of building structures is considered by all known and well proved Parameter of the Economic Damage. Application of offered model is illustrated on an example of probabilistic optimisation of steel community tower. The formulated approaches can be taken as a principle rationing of responsibility factor of buildings structures and also are used for definition of risks at insurance estimation of building structures.
Keywords: reliability optimum level, failure probability, failure risk, parameter of an economic damage, economic-probabilistic methods, stochastic loads, probabilistic optimisation, social and economic importance.