DETERMINATION OF DEFLECTIONS OF BEAMS WITH RHOMBIC PERFORATION OF THE WEB

Вестник МГСУ 7/2018 Том 13
  • Pritykin Aleksey Igorevich - Kaliningrad State Technical University (KSTU) Doctor of Technical Sciences, Professor, Department of Shipbuilding; ORCID ID 0000-0002-6597-8558, Kaliningrad State Technical University (KSTU), 1 Sovetsky avenue, Kaliningrad, 236040, Russian Federation; Этот e-mail адрес защищен от спам-ботов, для его просмотра у Вас должен быть включен Javascript .
  • Emelianov Konstantin Anatol’evich - «Litana» Leading Design Engineer, «Litana», 10 Vodnaya st., Kaliningrad, 236004, Russian Federation; Этот e-mail адрес защищен от спам-ботов, для его просмотра у Вас должен быть включен Javascript .

Страницы 814-823

Subject: due to a wide spread in construction practice of castellated beams with the rhomb-shaped perforation of the web, influence of parameters of such openings on beam’s deflections was investigated. Currently, in the Design Codes, both domestic and international, and also in Eurocode 3, the recommendations on determination of deflections of such beams are absent although they contain regulatory requirements. Research objectives: elaboration of analytical relationship, convenient for engineering calculations, for estimation of deflections of castellated beams with rhombic perforation of the web. Materials and methods: derivation of the deflection formula was carried out using one of the efficient methods for calculating deformations of perforated I-beams, based on the use of the theory of compound bars. Several numerical coefficients included in the expression for the stiffness coefficient of the elastic layer, formed by web-posts, were refined by means of finite element calculations. As a criterion for reliability of the analytical expression for deflections, the results of the finite element analysis of the beam, obtained with the ANSYS software complex, are used. Results: results of the study constitute the analytical relation for engineering calculations of deflections of castellated beams with the rhombic perforation of the web. The applicability of the proposed dependence to the calculation of deflections for beams with different shapes of rhombic perforation is verified by varying both the height of the openings and the width of the web-posts. In all cases, only the angle of inclination of the hexagonal sides, taken equal to 60°, remains fixed. An example of analysis of a perforated beam according to the method considered is given. For beams made by wasteless technology, when the width of the web-posts is equal to the horizontal side of the opening, for a rhomb-shaped perforation with a constant relative height of the openings, the total cut-out area remains practically unchanged for any width of the web-posts. A consequence of this is the weak influence of the relative width of the web-posts on deflections of beams with a fixed height of the openings. Conclusions: obtained engineering relationship will certainly be of practical interest to designers and can be recommended for including into the Design Codes of the Russian Federation.

DOI: 10.22227/1997-0935.2018.7.814-823

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INFLUENCE OF STRUCTURAL PECULIARITIES OF INTEGRATED RIBBED WOODEN SLABS ON THEIR STRESS-STRAIN BEHAVIOUR

Вестник МГСУ 5/2013
  • Zhadanov Viktor Ivanovich - Orenburg State University (OGU) Doctor of Technical Sciences, Associate Professor, Department of Structural Units; +7 (83532) 91- 21-23, +7 (83532) 27-11-42, Orenburg State University (OGU), 13 Pobedy pr., Orenburg, 460018, Russian Federation.
  • Tisevich Evgeniy Valer’evich - Orenburg State University (OGU) Candidate of Technical Sciences, Lecturer, Department of Structural Units; +7 (83532) 91-21-23, Orenburg State University (OGU), 13 Pobedy pr., Orenburg, 460018, Russian Federation.
  • Ukrainchenko Dmitriy Aleksandrovich - Orenburg State University (OGU) Candidate of Technical Sciences, Senior Lecturer, Department of Structural Units; +7 (83532) 27-93-72, Orenburg State University (OGU), 13 Pobedy pr., Orenburg, 460018, Russian Federation.

Страницы 35-42

In the article the authors provide their assessments and recommendations concerning the influence produced by the structural parameters onto the stress-strain behaviour of slabs having a wooden frame, if the veneering is integrated into the structural behaviour. The authors have completed a research into the pattern of distribution of regular compressive stresses over the width of the veneering surface. The authors have identified the values of reduction factors to be used to analyze integrated structures on the basis of simplified slab design and analysis patterns.The degree of heterogeneity of distribution of regular stresses over the width of the veneering is mainly driven by the rib-to-rib distance and the thickness of the veneering.Any unbiased assessment of the operational reliability of integrated wooden slabs requires development of specialized recommendations concerning their strength and rigidity analysis with account for the real parameters of structures adopted at the stage of their design.The research project was implemented by the authors with the support of the RF Ministry of Education and Science pursuant to Agreement 14.U02.21.0129.

DOI: 10.22227/1997-0935.2013.5.35-42

Библиографический список
  1. Dmitriev P.A., Zhadanov V.I. Bol’sherazmernye sovmeshchennye plity iz kleenoy drevesiny [Big-sized Integrated Slabs Made of Laminated Wood]. Orenburg, IPK GOU OGU Publ., 2007, 209 p.
  2. Endzhievsky L.V., Inzhutov I.S., Dmitriev P.P. Wooden Spatial Structures in Suberia. Spatial Structures in New and Renovation Projects of Buildings and Constructions: Theory, Investigations, Design, Erection. Proceedings of International Congress ICSS-98. June 22—26, 1998, Moscow, pp. 581—588.
  3. Dutko R. V?skum stanovenia spolup?sobiacej ?irky preglejkov?ch dosov?ch p?sov rebrov?ch panelov. Zbornik II. Celopolskeho symposia «V?skum uplatnenia dreva a materialov na b?ze dreva v stavebn?ch kon?trukci?ch». Politechnika ?tetinska, ?tetin, 1983, pp. 21—28.
  4. Grebenyuk G.I., Yan’kov E.V. Optimizatsiya parametrov bol’sherazmernykh rebristykh plit na osnove drevesiny [Optimization of Parameters of Big-sized Ribbed Slabs Made of Wood]. Problemy optimal’nogo proektirovaniya sooruzheniy [Problems of Optimal Design of Structures]. Sb. dokl. V-go Vseross. Seminara [Collected Reports of the 5th All-Russian Seminar]. Novosibirsk, NGASU (Sibstrin) Publ., 2005, pp. 110—119.
  5. Zhadanov V.I., Ukrainchenko D.A. Derevyannye panel’nye konstruktsii dlya seysmostoykogo maloetazhnogo stroitel’stva [Wood Panel Structures for Seismic Low-rise Construction]. Sovremennye stroitel’nye konstruktsii iz metalla i drevesiny [Modern Metal and Wooden Structures]. Odessa, OOO «Vneshreklamservis» Publ., 2011, No. 15, pp. 97—101.
  6. Zhadanov V.I., Tisevich E.V., Ukrainchenko D.A. Proektirovanie i raschet novykh konstruktivnykh form panel’nykh konstruktsiy na derevyannom karkase [Design and Analysis of New Constructions of Panel Structures Having Wooden Frames]. Orenburg, IPK GOU OGU Publ., 2011, 218 p.
  7. SP 64.13330.2011. Derevyannye konstruktsii [Construction Regulations 64.13330.2011. Wooden Structures]. Moscow, OAO «TsPP» Publ., 2011, 141 p.
  8. Inzhutov I.S., Deordiev S.V. Konstruktsiya i rezul’taty ispytaniy trekhugol’noy derevometallicheskoy blok-fermy [Structure and Testing Results Demonstrated by Three-angled Wood and Metal Frames]. Izvestiya vuzov. Stroitel’stvo. [News of Higher Education Institutions. Construction.] 1998, no. 10, pp. 129—134.
  9. Endzhievskiy L.V., Inzhutov I.S., Dmitriev P.A. Kombinirovannye iz stali, betona, dereva prostranstvennye konstruktsii blochnogo tipa [Composite Modular Spatial Structures Made of Steel, Concrete, Wood]. Krasnoyarsk, SFU Publ., IPK OGU Publ., 2008, 331 p.
  10. Kirilenko V.F., Lin’kov I.M. K voprosu eksperimental’nogo opredeleniya koeffitsienta privedennoy shiriny obshivki trekhsloynykh rebristykh paneley [Experimental Identification of Coefficient of Adjusted Width of Veneering for Three-layered Ribbed Panels]. Izvestiya vuzov. Stroitel’stvo i arkhitektura. [News of Higher Education Institutions. Construction and Architecture.] 1982, no. 6, pp. 127—129.

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Identification of pre-operation stresses and deformation of steel beams-ribsof composite floors

Вестник МГСУ 7/2013
  • Zamaliev Farit Sakhapovich - Kazan State University of Architecture and Civil Engineering (KazGASU) Candidate of Technical Sciences, Associate Professor, Department of Metal Constructions and Testing of Structures; +7 (843) 510-47-09., Kazan State University of Architecture and Civil Engineering (KazGASU), 1 Zelenaya St., Kazan, 420043, Russian Federation; Этот e-mail адрес защищен от спам-ботов, для его просмотра у Вас должен быть включен Javascript .

Страницы 33-39

Steel rib-reinforced beams are frequently used in the reconstruction of architectural monuments as a replacement for timber slabs. Insufficient amount of information about the stress-strain state of composite steel and concrete slabs limits their use in the domestic construction practice. The author describes the composition and geometric parameters of the structural solution. The author provides illustrations representing the reinforcement slab and anchors needed to track the behavior of composite concrete floors, the photographs featuring the voltage sensors attached to the shelves and the wall of a steel beam, the instrument used to measure the relative strain in the bottom of the beam. The technique employed by the author is used to track the dynamics of strains in the fiber discs, steel beams, and development of deflections. The author also describes the nature of stress on the top of the beam section. The experimental research has confirmed the assumption that the concrete setting time influences the stress-strain state of the steel beams as the basic elements of composite load-bearing floors. The author also provides the findings of the pilot studies.

DOI: 10.22227/1997-0935.2013.7.33-39

Библиографический список
  1. Streletskiy N.N. Stalezhelezobetonnye proletnye stroeniya mostov [Composite Steel and Reinforced Concrete Span Structures of Bridges]. Moscow, Transport Publ., 1981, 360 p.
  2. Gibshman E.E. Teoriya i raschet predvaritel’no napryazhennykh zhelezobetonnykh mostov s uchetom dlitel’nykh deformatsiy [Theory and Analysis of Pre-stressed Reinforced Concrete Bridges with Account for Long-term Deformations]. Moscow, Transport Publ., 1966., 366 ð.
  3. Golyshev A.B., Polishchuk V.P., Kolpakov Yu.A. Raschet sborno-monolitnykh konstruktsiy s uchetom faktora vremeni [Analysis of Prefab Monolithic Structures with Account for the Time Factor]. Kiev, Budivilnik Publ., 1969, 220 p.
  4. Sattler K. Composite Construction in Theory and Practice. The Structural Engineer, 1961, vol. 39, no. 4, p. 163.
  5. Bresler, Boris. Reinforced Concrete Engineering. Materials, Structural Elements, Safety. Vol. 1, Tohu Wiley and Sons, pp. 236—241.
  6. Perekrytiya stalezhelezobetonnye s monolitnoy plitoy STO 0047 [Reinforced Concrete Floor with a Monolithic Slab. Standards of Organizations 0047]. Moscow, TsNIIPSK, 2005, 43 p.
  7. EN 1992-1-1: Eurocode 2: Design of Concrete Structures — Part 1.1. General Rules and Rules for Buildings. CEN, 2007, 224 p.
  8. Almazov V.O. Problemy ispol’zovaniya Åvrokodov v Rossii [Problems of Application of the Eurocodes in Russia]. Promyshlennoe i grazhdanskoe stroitel’stvo [Industrial and Civil Engineering]. 2012, no. 7, pp. 36—38.
  9. Mirsayapov I.T., Zamaliev F.S., Shaymardanov R.I. Otsenka prochnosti normal’nykh secheniy stalezhelezobetonnykh izgibaemykh elementov pri odnokratnom staticheskom nagruzhenii [Assessment of Strength of Regular Sections of Composite Steel and Reinforced Concrete Elements in Bending If Exposed to Single-time Static Loading]. Sbornik statey RAASN [Collected Works of the Russian Academy of Architecture and Civil Engineering]. Nizhny Novgorod, NGASU Publ., 2001, pp. 247—250.
  10. Zamaliev F.S., Mirsayapov I.T. Raschet prochnosti stalezhelezobetonnykh izgibaemykh konstruktsiy na osnove analiticheskikh diagram [Strength Analysis of Composite Steel and Reinforced Concrete Structures in Bending on the Basis of Analytical Diagrams]. Razrabotka i issledovanie metallicheskikh i derevyannykh konstruktsiy. Sbornik nauchnykh trudov [Development of and Research into Metal and Timber Structures. Collection of Research Papers]. Kazan, KGASA Publ., 1999, pp. 142—149.

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STEPWISE CALCULATION OF THE TRANSVERSE BENT OF A BUILDING FRAME

Вестник МГСУ 9/2016
  • Shishov Ivan Ivanovich - Vladimir State University named after Alexander and Nikolay Stoletovs (VISU) Candidate of Technical Sciences, Associate Professor, Department of Building Structures, Vladimir State University named after Alexander and Nikolay Stoletovs (VISU), 87 Gor’kogo str., Vladimir, 600000, Russian Federation; Этот e-mail адрес защищен от спам-ботов, для его просмотра у Вас должен быть включен Javascript .
  • Ryazanov Maksim Aleksandrovich - Vladimir State University named after Alexander and Nikolay Stoletovs (VISU) postgraduate student, Department of Building Structures, Vladimir State University named after Alexander and Nikolay Stoletovs (VISU), 87 Gor’kogo str., Vladimir, 600000, Russian Federation; Этот e-mail адрес защищен от спам-ботов, для его просмотра у Вас должен быть включен Javascript .
  • Maksimenko Marina Olegovna - Vladimir State University named after Alexander and Nikolay Stoletovs (VISU) Master student, Department of Building Structures, Vladimir State University named after Alexander and Nikolay Stoletovs (VISU), 87 Gor’kogo str., Vladimir, 600000, Russian Federation; Этот e-mail адрес защищен от спам-ботов, для его просмотра у Вас должен быть включен Javascript .
  • Vichuzhanina Yuliya Aleksandrovna - Vladimir State University named after Alexander and Nikolay Stoletovs (VISU) Master student, Department of Building Structures, Vladimir State University named after Alexander and Nikolay Stoletovs (VISU), 87 Gor’kogo str., Vladimir, 600000, Russian Federation; Этот e-mail адрес защищен от спам-ботов, для его просмотра у Вас должен быть включен Javascript .

Страницы 51-61

Deformation of plane core systems consisting of vertical and horizontal cores, which are rigidly or hingedly interconnected in the assembly, is considered in the article. Building frames of industrial and civil buildings, the columns of which undergo eccentrical compression and geometrically nonlinear deformation, have been investigated. There arises a necessity to solve the issues of strength, rigidity and stability. An algorithm and a computer program for solving this issue is proposed. The basic system of the deflection method and its suppositions has also been applied. The solution indicated stable convergence. Dependability between internal stresses of the cross section has been determined with account of the arising deformations and the effect of the linear compressing force that provides the accounting of geometrical nonlinearity. The examples illustrating high accuracy of the dislocation determination for the deformed-compressed core and the crippling load of the core system have been given. Finite-difference method that allows employing the cores the rigidity of which vary within their length limits has been used. The stability of the building under the core increment has also been investigated. An algorithm and a computer program for a plane core system calculation made up of vertical or horizontal cores rigidly or hingedly interconnected in the assembly have been worked out. Auxiliary core offsets and displacements of the system core joints have been taken as the basic unknown variables that allow making calculations with pre-set safety factor, rigidity and stability. The proposed stepwise method of the core system calculation is notable for its simplicity for programming. As the calculations testify, this method provides high accuracy of solutions. The applied method of finite differences may serve as a prerequisite for taking physical non-linearity of reinforced concrete into account.

DOI: 10.22227/1997-0935.2016.9.51-61

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Stress-strain properties of concrete made of the chip of crushed concrete

Вестник МГСУ 10/2016
  • Bezgodov Igor’ Mikhaylovich - Moscow State University of Civil Engineering (National Research University) (MGSU) research worker, Moscow State University of Civil Engineering (National Research University) (MGSU), 26 Yaroslavskoe shosse, Moscow, 129337, Russian Federation; Этот e-mail адрес защищен от спам-ботов, для его просмотра у Вас должен быть включен Javascript .
  • Pakhratdinov Alpamys Abdirashitovich - Moscow State University of Civil Engineering (National Research University) (MGSU) postgraduate student, Department of Construction Materials, Moscow State University of Civil Engineering (National Research University) (MGSU), 26 Yaroslavskoe shosse, Moscow, 129337, Russian Federation; Этот e-mail адрес защищен от спам-ботов, для его просмотра у Вас должен быть включен Javascript .
  • Tkach Evgeniya Vladimirovna - Moscow State University of Civil Engineering (National Research University) (MGSU) Doctor of Technical Sciences, Professor, Department of Construction Materials, Moscow State University of Civil Engineering (National Research University) (MGSU), 26 Yaroslavskoe shosse, Moscow, 129337, Russian Federation; Этот e-mail адрес защищен от спам-ботов, для его просмотра у Вас должен быть включен Javascript .

Страницы 24-34

The use of crushed concrete scrap, the volume of which is quite essential, is constrained by the regulatory framework and poor studies of stress-strain characteristics of concrete. In order to solve this problem it is necessary to conduct comparative experiments with the aim of obtaining the strength and deformation characteristics of concrete, which will allow determining the possible list of structures for industrial and civil objects. Tests were carried out on the assessment of prism strength, modulus of elasticity, coefficient of lateral deformation, the maximum compression strain, tensile strength in bending as well as tests of reinforced concrete beams produced of the same compositions for evaluation of failure load, strain and deflection diagram construction with the aim of identifying distinctive characteristics of strength and deformation characteristics of concrete obtained of crushed concrete waste in comparison with the characteristics of concrete made of granite macadam. The results of the investigation show that the use of crushed concrete waste in reinforced concrete structures is quite allowable and there is no need in serious adjustments in the calculations, especially for concretes of low grades.

DOI: 10.22227/1997-0935.2016.10.24-34

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ON THE INFLUENCE OF A FREE SUPPORT RAKE ON THE RIGIDITY OF A GIRDER BEAM

Вестник МГСУ 10/2016
  • Kirsanov Mikhail Nikolaevich - National Research University, “Moscow Power Engineering Institute” (MPEI) Doctor of Physical and Mathematical Sciences, Professor, Department of Robotics, Mechatronics, Dynamics and Strength of Machines, National Research University, “Moscow Power Engineering Institute” (MPEI), 14 Krasnokazarmennaya str., Moscow, 111250, Russian Federation; Этот e-mail адрес защищен от спам-ботов, для его просмотра у Вас должен быть включен Javascript .

Страницы 35-44

Analytical solutions have definite advantages over numerical ones. It is quite complicated to find solutions for a whole class of structures different in the number of bars or panels if we speak about girder trusses. The solutions obtained in a symbol form may be analytically investigated depending on all the parameters characterizing the structure. This allows educing the distinctive features of the systems and finding possibilities for optimization in terms of mass, strength and rigidity. At the present time the induction method is the most efficient to obtain analytical solutions for a number of trusses. Using computer mathematics system Maple the author obtained analytical expressions for deflection of a flat statically determinate parallel-flanged elastic truss depending on the number of panels at uniform and concentrated load. It is shown that the rake angle of a free support greatly influences the stiffness of a structure. The graphic charts of the dependence of deflection from the number of panels at a fixed span length and a given load show extremum. The author obtains asymptotic characteristics of the deflection and expressions for stresses in the most compressed and tension bars. It is also shown that the solution type for a deflection isn’t changed in case of different loading types and has a form of a polynomial of not more than third degree in correspondence with the number of panels in half of a span.

DOI: 10.22227/1997-0935.2016.10.35-44

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ANALYTICAL STUDY ON THE RIGIDITY OF STATICALLY DETERMINATE SPATIAL TRUSS

Вестник МГСУ 2/2017 Том 12
  • Kirsanov Mikhail Nikolaevich - National Research University Moscow Power Engineering Institute (MPEI) Doctor of Physical and Mathematical Sciences, Professor, Department of the Theoretical Mechanics and Mechatronics, National Research University Moscow Power Engineering Institute (MPEI), 14 Krasnokazarmennaya str., Moscow, 111250, Russian Federation.

Страницы 165-171

Beamlike spatial two-layer symmetric truss is formed by four plane trusses connected by the long sides, and rests on four corner points. Stresses in truss components are defined in a symbolic manner by the method of joint isolation using the Maple computer algebra system. Matrix of the set of equilibrium equations is formed in a cycle according to the number of bars of the truss. For calculation of deflection the Maxwell-Mohr formula is used. The solution is framed for the case of various bar sectional areas and is generalized to an arbitrary number of panels by the method of induction. Operators for formation and solution of recurrence equations are involved for determination of general terms of sequences of coefficients. Certain limit performance and asymptotic characteristics of the structure are found. Formulas for stresses in the most compressed and stretched truss components are derived. Model of statically determinate spatial two-layer truss is proposed. Exact analytical expression for deflection of the truss under action of a concentrated force is found. The used algorithm allows to expand the solution to an action of other loads and methods of supporting. Inhomogeneous distribution of material throughout the structure bars is taken into account in the solution. It enables a designer to choose the most optimal combination of design parameters without making numerical calculations in specialized packages. The proposed two-layer trusses may find practical use in roofs of buildings and structures where a natural interior volume creates additional thermal protection, herewith providing an improvement of strength.

DOI: 10.22227/1997-0935.2017.2.165-171

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EXPERIMENTAL RESEARCH INTO THE INFLUENCE PRODUCED BY PROCESS-RELATED AND STRUCTURAL PARAMETERSON THE BEARING CAPACITY OF METAL BEAMS WITH CORRUGATED WEBS

Вестник МГСУ 2/2013
  • Zubkov Vladimir Aleksandrovich - Samara State University of Architecture and Civil Engineering (SSUACE) Candidate of Technical Sciences, Professor, Department of Steel and Timber Structures, Samara State University of Architecture and Civil Engineering (SSUACE), 194 Molodogvardeyskaya st., Samara, 443001, Russian Federation; Этот e-mail адрес защищен от спам-ботов, для его просмотра у Вас должен быть включен Javascript .
  • Lukin Aleksey Olegovich - Samara State University of Architecture and Civil Engineering (SSUACE) assistant lecturer, Department of Metal and Timber Structures; +7 (846) 332-14-65, Samara State University of Architecture and Civil Engineering (SSUACE), 194 Molodogvardeyskaya st., Samara, 443001, Russian Federation; Этот e-mail адрес защищен от спам-ботов, для его просмотра у Вас должен быть включен Javascript .

Страницы 37-46

The article covers the experimental research into corrugated web beams exposed to the concentrated static load that has varied values of the width of load exposure. The authors describe the methodology of the experiment, instruments and machines involved in it, as well as the findings of the tests.Six beams with sinusoidal webs were selected for testing purposes. The beams were 6, 9 and 12 m long, and their cross sections were 500, 750 and 1,250 mm long. All beams were tested as single-span simply supported structures with hinged rigidly or loosely fixed supports.Beam tests have demonstrated that any failure to adhere to the beam manufacturing technology may seriously affect the load-bearing capacity of a beam. Any deviation of longitudinal axis flanges of beams from the longitudinal axis of a corrugated web in excess of 3 mm adversely affects the bearing capacity of beams and contributes to the overall beam stability loss.The research findings have demonstrated that the limit state of tested beams arises due to the stress in the web corrugation.

DOI: 10.22227/1997-0935.2013.2.37-46

Библиографический список
  1. Azhermachev G.A. Ob ustoychivosti volnistoy stenki pri deystvii sosredotochennoy nagruzki [On Stability of a Wavy Wall Exposed to the Concentrated Load]. Izvestiya vuzov. Stroitel’stvo i arkhitektura [News of Higher Education Institutions. Construction and Architecture]. Novosibirsk, 1963, no. 3, pp. 50—53.
  2. Baranovskaya S.G. Prochnost’ i ustoychivost’ gofrirovannoy stenki stal’noy dvutavrovoy balki v zone prilozheniya sosredotochennykh sil [Strength and Stability of the Corrugated Steel Web I-beam Exposed to Concentrated Forces]. Novosibirsk, 1990, 18 p.
  3. Biryulev V.V., Ostrikov G.M., Maksimov Yu.S., Baranovskaya S.G. Mestnoe napryazhennoe sostoyanie gofrirovannoy stenki dvutavrovoy balki pri lokal’noy nagruzke [Local Stress State of the Corrugated Web of I-beams Exposed to the Local Load]. Izvestiya vuzov. Stroitel’stvo i arkhitektura [News of Higher Education Institutions. Construction and Architecture]. Novosibirsk, 1989, no. 11, pp. 11—13.
  4. Krylov I.I., Kretinin A.N. Effektivnye balki iz tonkostennykh profiley [Effective Thin-walled Beams]. Izvestiya vuzov. Stroitel’stvo. [News of Higher Education Institutions. Construction]. Novosibirsk, 2005, no. 6, pp. 11—14.
  5. Laznyuk M.V. Balki z tonkoyu poperechno gofrovanoyu st³nkoyu pri d³¿ statichnogo navantazhennya [Beams with a Thin Transversely Corrugated Web Exposed to the Static Load]. Kiev, 2006, 18 p.
  6. Stepanenko A.N. Issledovanie raboty metallicheskikh balok s tonkimi gofrirovannymi stenkami pri staticheskom zagruzhenii [Research into Behaviour of Thin-walled Corrugated Web Metal Beams Exposed to Static Loading]. Sverdlovsk, 1972, 20 p.
  7. Stepanenko A.N. Ispytanie alyuminievykh balok s gofrirovannoy stenkoy [Testing of Aluminum Beams with a Corrugated Web]. Izvestiya vuzov. Stroitel’stvo i arkhitektura [News of Higher Education Institutions. Construction and Architecture]. Novosibirsk, 1970, no. 1, pp. 31—35.
  8. Pichugin S.F., Chichulina K.V. Eksperimental’n³ dosl³dzhennya balok z prof³l’ovanoyu st³nkoyu [Experimental Researches into Beams with Profiled Surfaces]. Visnik DNABA [Proceedings of Donbas National Academy of Civil Engineering and Architecture]. 2009, no. 4 (78), pp. 161—165.
  9. Pasternak H., Kubieniec G. Plate Girders with Corrugated Webs. Journal of Civil Engineering and Management. 2010, no. 16 (2), pp. 166—171.
  10. Gao J., Chen B.C. Experimental Research on Beams with Tubular Chords and Corrugated Webs. Tubular Structures XII. Proceedings of Tubular Structures XII. Shanghai, China, 8—10 October 2008, pp. 563—570.

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STUDYING DEFORMATIONS OF AN FLAT TRUSS STRUCTURE STATICALLY INDETERMINATED EXTERNALLY

Вестник МГСУ 8/2017 Том 12
  • Kirsanov Mikhail Nikolaevich - National Research University Moscow Power Engineering Institute (MPEI) Doctor of Physical and Mathematical Sciences, Professor, Department of the Theoretical Mechanics and Mechatronics, National Research University Moscow Power Engineering Institute (MPEI), 14 Krasnokazarmennaya str., Moscow, 111250, Russian Federation.
  • Suvorov Alexander Pavlovich - Moscow State University of Civil Engineering (National Research University) (MGSU) Candidate of Technical Sciences, Senior Lecturer, Department of Applied Mathematics, Moscow State University of Civil Engineering (National Research University) (MGSU), 26 Yaroslavskoe shosse, Moscow, 129337, Russian Federation.

Страницы 869-875

A flat statically determinate parallel-chord truss structure has a cross-shaped grid and rests upon two rigid pin-bearing supports. Loads in bars are determined in a symbol form using the method of joint isolation by the computer mathematics Maple system. The peculiarity of the considered truss structure is its external static indeterminacy. In fact, all efforts and reactions of supports can be determined from the equilibrium conditions. But the inconvenience is necessary to consider the equilibrium of all the nodes of the truss. The Ritter cross-section method is not applicable to this truss structure. The sections that cut the truss into two parts and pass through the three rods, here exist only for several rods of the extreme panels. The purpose of this paper is to calculate a truss structure with a different number of panels in analytical and numerical form. Finite element calculation method with the use of software LISA 8.0 is applied. It’s noted that a truss structure is kinetically changeable when the number of spans is odd. The corresponding plan of probable velocities is given. In order to receive analytic dependence of deflection on the span number, the induction method and Maxwell-Moor formula has been applied. The operators of the compilation and solution of recurrence equations are involved in determining the general terms of the coefficient sequences. The formulas for calculation of loads in the most compressed bars of a truss structure were received.

DOI: 10.22227/1997-0935.2017.8.869-875

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INFLUENCE OF HIGH-STRENGTH REINFORCEMENT WITHOUT ADHESION TO CONCRETE ON STRENGTH OF CAST-IN-SITU BEAMLESS FLOORS

Вестник МГСУ 8/2017 Том 12
  • Osipenko Yuri Grigoryevich - «Monolit» Candidate of Technical Sciences, Associate Professor, First Deputy General Director, «Monolit», 50 Olimpiyskiy prospekt, Mytischi, Moscow region, 141006, Russian Federation.
  • Kuznetcov Vitaliy Sergeevich - National Research Moscow State University of Civil Engineering Candidate of Technical Sciences, Associate Professor, Department of Architecture and Construction Design, National Research Moscow State University of Civil Engineering, 26 Yaroslavskoe shosse, Moscow, 129337, Russian Federation.
  • Shaposhnikova Yulia Alexandrovna - National Research Moscow State University of Civil Engineering Senior Lecturer, Department of Reinforced Concrete and Stone Structures, National Research Moscow State University of Civil Engineering, 26 Yaroslavskoe shosse, Moscow, 129337, Russian Federation.

Страницы 885-891

The influence and location of prestressed high-strength reinforcement without adhesion to concrete on the strength of a beamless floor panel is considered. The work is aimed at clarifying the methodology for calculating the strength of cast-in-situ beamless floor with mixed reinforcement, where reinforcement is used in a plastic shell of monostrend type without adhesion to concrete for the most complete use of the strength characteristics of the panel material. The aim of the study is to determine the level of influence and location of prestressed reinforcement without adhesion to concrete on the strength of a panel of cast-in-situ beamless floor, as well as comparison of the results obtained for the stresses of ropes in panels with contour and diagonal arrangement of prestressed reinforcement. The shape of the rope position is represented by a part of the parabola passing through the points of the rope support. On the support, the vertical and horizontal components of the reaction are determined by the longitudinal force in the rope and the exit angle of the guy rope. 9х9m cast-in-situ beamless floor panels in two variants were investigated: with diagonal and contour stressing steel. The values of increment in stresses in the ropes and the resulting values at various prestress and deflection levels, presented in the form of tables and graphs, have been calculated. According to the results of the study, the use of high-strength prestressed ropes without adhesion to concrete, as an additional working reinforcement, reduces deflections of the panels and lowers consumption of common reinforcement. The results indicate a relative decrease in efficiency of using rope strength along with an increase in the initial prestress level. From the point of ensuring load-bearing capacity, the contour positioning of ropes is preferable, due to more complete use of strength of high-tensile reinforcement. To meet the requirements of ultimate limit states, the establishment of the pre-stress level of ropes should be carried out taking into account probable achievement of the design stress in high-strength reinforcement .

DOI: 10.22227/1997-0935.2017.8.885-891

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ANALYTICAL CALCULATION OF DEFLECTION OF RECTANGULAR SPATIAL ROOF STRUCTURE

Вестник МГСУ 5/2018 Том 13
  • Kirsanov Mikhail Nikolaevich - National Research University, “Moscow Power Engineering Institute” (MPEI) Doctor of Physical and Mathematical Sciences, Professor, Department of Robotics, Mechatronics, Dynamics and Strength of Machines, National Research University, “Moscow Power Engineering Institute” (MPEI), 14 Krasnokazarmennaya str., Moscow, 111250, Russian Federation; Этот e-mail адрес защищен от спам-ботов, для его просмотра у Вас должен быть включен Javascript .

Страницы 579-586

Subject: obtaining an analytical solution to the problem of deflection of a spatial structure with an arbitrary number of panels, which remains valid for a wide class of constructions of the proposed structure. Research objectives: the main purpose of this work is to derive dependence of truss deflection on the number of panels, on the magnitude of the load and dimensions of the structure. Materials and methods: the deformability of a truss over rectangular plan with vertical supports on all lateral sides, made of steel or aluminum alloys is estimated by the vertical displacement of the central node, to which the force is applied. The forces in the rods and supports are determined by the method of joints. Generalization of the particular solutions found for a sequence of trusses with various number of panels to an arbitrary number of panels is obtained by induction. All symbolic transformations and solutions are performed in the computer mathematics system Maple. Using special operators of the Maple software, homogeneous linear recurrence equations are derived and solved, which are satisfied by the terms in the sequences of coefficients of the desired formula. Results: the resulting deflection formula constitutes a cubic polynomial expressed in terms of the number of panels. The graphs of the dependence of deflection on the number of panels and on the height are plotted. Formulas for forces in characteristic rods are derived. Conclusions: the proposed model of a statically determinate spatial truss structure with supports all over the contour allows an analytical solution for deflection and its generalization to an arbitrary number of panels. The results are numerically verified and can be used as benchmark cases for estimation of the accuracy of numerical solutions. The obtained formulas are most effective for large number of panels, i.e., when numerical methods based on solving high-order linear systems require significant machine resources and are prone to uncontrolled accumulation of round-off errors.

DOI: 10.22227/1997-0935.2018.5.579-586

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Calculating model of a frame type planar truss having an arbitrary number of panels

Вестник МГСУ 10/2018 Том 13
  • Mikhail N. Kirsanov - National Research University “Moscow Power Engineering Institute” (MPEI) Doctor of Phisical and Mathematical Sciences, Professor, Department of robotics, mechatronics, dynamics and strength of machines, National Research University “Moscow Power Engineering Institute” (MPEI), 14 Krasnokazarmennaya st., Moscow, 111250, Russian Federation.

Страницы 1184-1192

ABSTRACT Introduction. The subject of the study is the kinematic variability and deformations of a planar statically-determinate elastic truss with a horizontal bolt, lateral supporting trusses and a cross-shaped grid under the action of various types of static loads. The structure has three movable supports and one fixed support. Objectives - derivation of formulas giving the dependence of the deflection of the structure in the middle of the span and the displacement of one of the three movable supports from the dimensions, load and number of panels; analysis of the kinematic variability and derivation of the analytical dependence of the forces in the rods of the middle of the span from the number of panels. Materials and methods. Forces in the rods of the truss are calculated in symbolic form by cutting out nodes using the Maple symbolic and numeric computational environment. In order to calculate the deflection, the Maxwell - Mohr formula was used. Calculation formulas for the deflection and displacement of the support were derived using the induction method based on the results of analytical calculations of a number of trusses with a different number of panels in the crossbar and lateral support trusses. The special operators of the genfunc package for managing the rational generating functions of the Maple system were used to identify and solve the recurrence equations satisfied by the sequences of coefficients of the formulas for deflection and forces. It is assumed that all the rods of the truss have the same rigidity. Results. Several variants of loads on the truss are considered. A combination of panel numbers is found in which the truss becomes kinematically variable. The phenomenon is confirmed by the corresponding scheme of possible velocities. All required dependences have a polynomial form by the number of panels. The curves of the dependence of the deflection on the number of panels and on the height of the truss are constructed in order to illustrate the analytical solutions. Conclusions. The proposed scheme of a statically determinate truss is regular, allowing a fairly simple analytic solution of the deflection problem. The curves of the identified dependencies have significant areas of abrupt changes, which can be used in problems of optimising the design by weight and rigidity.

DOI: 10.22227/1997-0935.2018.10.1184-1192

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