O.I. Golodnov
Substantiation of a service life extension for steel structures
Open Join-Stock Company «V.Shimanovsky Ukrainian Research and Design Institute of Steel Construction»
Abstract. The paper is devoted to the solution of an urgent problem of estimating operating conditions and a possibility of extending the operation life of building structures. There is considered a practicability of using a complex procedure of estimating a structure stressed-deformed state relying on the results of visual and instrumental examination and mathematical simulation methods aimed at the evaluation of operating conditions. Determination of operating conditions is carried out according to the normative documents in force. Simulation of the established operating conditions to determine rated forces is done by the finite elements method. There is put forward a procedure of calculating a residual life of structures keeping in mind the established operating conditions and a possibility of extending structure service life. This procedure can be used on designing structures for enterprises with a hostile environment and for areas where the development of uneven deformations in the base is possible. Determination of the residual life of structures will make it possible to come to final conclusions as to the potentials of a further use and to prepare recommendations for reinforcement or protection from the hostile environment action.
Keywords: operation of structures, defects and damages, estimation of operating conditions, residual life, extension of operation.
Yu.I. Kudishyn, N.Ya. Mikhalev
On survivability of bearing structures of the ice stadium in Hodynskoye pole, Moscow, Russia
Moscow State University of Civil Engineering
Abstract. Methodical recommendations for estimating a survivability of bearing structures were elaborated (the Ice Stadium in Moscow was taken as an example). The essential of the methods is to solve the dynamic equation on the behavior of a structure in case when its key elements suddenly fail. The initial parameters of a mathematical model were obtained by a physical modeling on a scale of one to ten. There was done a dynamic design of a roof structure of the Ice Stadium under different operating conditions including the state caused by a sudden local failure of a supporting ring, fibers and diagonal braces. The design results were compared with the results of dynamic tests of a roof model. Their good agreement in the range of the investigations done indicates perspectivities of the suggested procedure of survivability test of complex building objects in the structures of the 1st level of responsibility.
Keywords: survivability, dynamic design, physical modeling, steel structures.
V.О. Popov
Simulation of a deflected mode of a high-precision joining of amusement-towers with the help of the program “Cosmos-2004” to optimize the structure
Vinnitsa National Technical University
Abstract. There is given an analysis of constructive decisions of intersectional angle joints of modern amusement towers, there is shown a rationality of using an original high-precision detachable joining on bushes and a deadbolt as a more rational joining than the classic flange joint, there is considered a modeling of a deflected mode of this joint under tensile loads with the use of the modern program complexes “Cosmos-2004” and “Lira 9.0”. Having analyzed equivalent tensions for different structural parameters of the joint elements, we found the most efficient constructive form of joining. “COSMOS-2004” has been verified, and it was proved that the results obtained with its help are adequate, it was also proved that the use of this complex to analyze the deflected mode of steel structure elements in comparison with the complex “Lira 9.0” is more rational.
Keywords: high-precision detachable knot joint, deflected mode, reduced stresses.
M.I. Kazakevych
Urgent problems of high-rise building aerodynamics
Donbas National Academy of Civil Engineering and Architecture
Abstract. Major problems of a high-rise building interaction with the wind flow from the point of view of the flow regime variety and triune discomfort developments are given in this paper. There are considered fundamental peculiarities of a high-rise building spatial flow-round. A special attention is paid to the present-day aspects of the high-rise building aerodynamics. There are given recommendations as to fixing maximum values of aerodynamic coefficients in the rarefaction zones on the high-rise building lateral surfaces and on the roof. The triune developments of discomfort inside the building and in pedestrian zones inside the built-up territories are considered in details. Prospective and effective ways of stabilizing wind flows in a pedestrian zone, as well as the methods of stabilizing aero-elastic reactions of the high-rise buildings of the tower type are suggested in the paper..
Keywords: high-rise building, wind flow, spatial flow-round, discomfort, stabilization.
D.O. Bannikov, M.I. Kazakevych
A comparative analysis of construction diagrams of steel bunker capacities
Dnipropetrovs’k V. Lazaryan National University of Railway Transport
Abstract. In the paper there are considered four main modern constructive variants of steel capacities for bulk materials including a design concept on the base of using a panel scheme of the compound corrugated elements suggested by the authors. A comparative analysis of their stress-stain state on the base of FEM with the use of a design computer system SCAD was made. Following the investigations, it was found out that the use of the panel scheme of the compound corrugated elements not only theoretically allows decreasing stresses up to 35 %, but considerably increases a regularity of their arrangement in a structure. Its special rigidity increases considerably herewith, that being an important factor for structures intended for operating with bulk materials. Some other constructive schemes presented allow to obtain similar results only in part. The most preferable variant to be considered is the variant with the use of V-shaped stiffening rib instead of traditional ones.
Keywords: bunker, bin capacity, panel constructive scheme, FEM, granular materials.