Sergey Pichugin, Oleksandr Zyma
Method for reliability estimation of the main pipeline steelwork structure
Poltava National Technical Yuri Kondratyuk University
Abstract. Factors affecting the reliability of steel pipelines are under consideration in the paper. A selection of probability models is presented and the random variables magnitude distribution is determined for internal pressure of the product transported and for the thermal gradient in the buried pipeline. The method for estimating the reliability of such structures is suggested, the comparative analysis for pipelines having different external diameters and for different internal pressure values of the product transported is presented. The problem of choosing the best level of pipelines safety is considered. The formulated and developed probabilistic method is distinctive in its analytical simplicity. The given method can be used at the design stage as well as during operation of transit pipeline: in the process of decision making of its major repairs, determination of safety power pressure under the practical engineering state.
Keywords: main pipeline, reliability of structures, loads and impacts random variables, probabilistic method.
Volodymyr Mushchanov, Iurii Priadko
Fundamental approaches towards joints operation at reliability designs of suspension bar roofs
Donbas National Academy of Civil Engineering and Architecture
Abstract. The problems of reliability of large-span suspension roofs have been analyzed. The fundamental approaches to regard of joints reliability in designs of reliability of suspension bar roofs have been described. The bearing joints of sheeting of curved and rigid filament to the external and internal outline, interstitial joints of the top and lower chords of bearing filament, sheeting joints of vertical and horizontal connections to the bearing filaments of the roof have been accepted as the designed data. The logical and probabilistic methods of estimation of joints reliability and methods based on the mathematical statistics have been accepted in the analysis. Carried out structural design of reliability of joints of suspension roofs has shown that they are mainly described by sequential schemes including parallel connections of dependent elements corresponding to multi-elementary connections selected in store. Correlation regard between the elements of structural schematic drawings of joints in consequence of generality of intensification and strength of steel allows to reduce quantity of elements in the scheme and increase resulting estimation of reliability.
Keywords: space and bar suspension shell, curved and rigid filaments, joint, reliability indices, stressed-strained state, logical and probabilistic methods.
Yevgen Gorokhov, Anatoliy Yugov, Roman Ignatenko
The planning of effective delivery schemes of metal frame tower lattice supports with the help of motor transport as a part of production project works
Donbas National Academy of Civil Engineering and Architecture
Abstract. In the paper the requirements for the development of projects of transport schemes delivery of metal constructions, the necessity of development as part of production project works PTSDMC in installation of metal lattice tower transmission towers as a way to minimize the total cost of construction and installation work, have been determined. The native and foreign experience in transportation of metal structures, the structure of the transport process has been analyzed, and examined schemes and methods of delivery of metal transmission towers road have been considered. The main factors, affecting the duration and the costs of MC transportation have been determined and considered. Factors and the choice of technology, the size and weight of units shipped metalwork, form a unit load, the degree of utilization of transport units, as well as the selection of traffic schemes have been also determined.
Keywords: effective delivery schemes, metal frame tower lattice supports, motor transport, production project works, industrial methods of construction, Scheme of Transport Project Delivery Metal Construction.
Anatoly Perelmuter a, Sergey Pichugin b
About one characteristic of building objects reliability
a SCAD Soft Ltd., b Poltava National Technical University named of honor Yuri Kondratyuk
Abstract. Functional limit-state design of construction does not take into account all structural states, besides limit-states. Design requirement to the object is represented in regard to these limit states. Real work fixes eyes on feasibility of some unexpected neither normative documents nor designer forecast random action on design object. The special measure of the indicated quality of structure, named mobilization, demonstrated, as much as the system can respond on local action, unexpected dithering in time, is suggested. Immobility of construction has to cause to heightened level of awareness and the usage of protection measures, dependent measures of warning principles, such as tighten control or structural concept, have to be their basis. It has been suggested to take amount, found out by multiplying of reliability index on rate of time scale between flood-back of load process as level of design value and expected useful life of constructiond.
Keywords: random load, outliers for a calculation level, reliability.
Yaroslav Nazim
Calculation procedure of the overhead power transmission lines of high reliability as part of unified mechanical system
Donbas National Academy of Civil Engineering and Architecture
Abstract. Calculation procedure for overhead power transmission lines of high reliability has been developed, which allows to determine stresses and strains in the conductors, ground-wire cables, fittings and PTL towers as part of a unified mechanical system. Calculation procedure takes into account a number of interrelated factors – climatic conditions, design parameters of overhead lines (length of span, sag, electrical clearances), terrain profile and plan (scheme) PTL, calculation modes and load combinations, etc. It has been implemented in the program complex «MISI1», which was developed in the Donbas National Academy of Civil Engineering and Architecture. A series of load calculations on support structure for section line of the same type of conditional constructive solutions and terrain profile located in different climatic conditions of Ukraine has been performed to verify the convergence of the results determined using this calculation procedure with the data obtained on the basis of the recommendations of the European Committee of Electrotechnical Standardization (CENELEC – EN 50174). Calculation procedure has been tested on a real object of intersystem value – double circuit large transmission line crossing 154 kV «Kremenchuk Hydroelectric Station – Kremenchuk Heat and Power Station» on the river Dnieper.
Keywords: calculation procedure, overhead power transmission line (PTL), stress-strain state, climatic loads, software package.