Published since 1923
DOI: 10.33622/0869-7019
Russian Science Citation Index (RSCI) на платформе Web of Science



Contents of issue № 7 (july) 2016

  • JUBILEE OF ORGANIZATION
  • The Department of Reinforced Concrete and Masonry Structures of MISI-MGSU: 85 Years
  • TAMRAZYAN A. G.
  • BUILDING MECHANICS
  • Assessing the Impact of Structural Parameters on the Reliability of a Platform Joint of Panel Buildings by the Method of Statistical Modeling
  • UDC 624.078:69.057.1
    Ashot G. TAMRAZYAN, e-mail: tamrazian@mail.ru
    Denis S. DEKHTEREV, e-mail: 9201177874@mail.ru
    National Research Moscow State University of Civil Engineering, Yaroslavskoe shosse, 26, Moscow 129337, Russian Federation
    Abstract. The development of panel house building in the middle of the XX century addressed the problem of safety of panel buildings at the expiration of their standard operational life. One of the major problems when assessing the reliability of the panel building is the assessment of the reliability of the platform panel joints. Improving methods of inspection and calculation of platform joints is a main way of improving the safety of operated prefabricated buildings. The paper lists the parameters that affect the bearing capacity and initial reliability of platform joints. The probability distribution function, reliability index and failure probability of structures are shown. To assess the influence of design parameters on the reliability of the platform joint, the statistical experiment was conducted. Results of scientific studies and in-place tests with real parameters of designs were the initial data for the experiment. A significant excess of the degree of influence of some parameters on the reliability of the joint has been established; this makes it possible to take into account the experiment results in the practice of design and construction of buildings.
    Key words: reliability and safety of structures, joint platform, probability distribution function, reliability index, probability of failure.
  • REFERENCES
    1. Dudina I. V., Tamrazjan A. G. Ensuring quality precast concrete at the manufacturing stage. Zhilishhnoe stroitel'stvo, 2001, no. 3, pp. 8-10. (In Russian).
    2. Tamrazyan A. G. The basic principles of risk assessment in the design of buildings and structures. Vestnik MGSU, 2011, no. 2-1, pp. 21-27. (In Russian).
    3. Sat'janov S. V., Pilipenko P. B., Kotel'nikov V. S., et. al. Risks in the construction activity in the construction, reconstruction and capital repairs of building objects and their minimization. Montazhnye i special'nye raboty v stroitel'stve, 2011, no. 3, pp. 12-13. (In Russian).
    4. Tamrazyan A. G., Filimonova E. A. On the effect of reducing the hardness of concrete slabs on the carrying capacity with long-term effect of load. Promyshlennoe i grazhdanskoe stroitel'stvo, 2012, no. 7, pp. 30-32. (In Russian).
    5. Kljueva N. V., Tamrazyan A. G. The fundamental properties of structural systems, reducing the risk of failure of the building elements. Izvestija Jugo-Zapadnogo gosudarstvennogo universiteta, 2012, no. 5-2(44), pp. 126-131. (In Russian).
    6. Tamrazyan A. G., et. al. Snizhenie riskov v stroitel'stve pri chrezvychajnyh situacijah prirodnogo i tehnogennogo haraktera [Reducing the risk in construction in emergency situations of natural and man-made]. Moscow, MISI-MGSU Publ., 2012. 304 p. (In Russian).
    7. Tamrazyan A. G. Calculation of structural elements at a given reliability and normal distribution and load bearing capacity. Vestnik MGSU, 2012, no. 10, pp. 109-115. (In Russian).
    8. Narushevich A. N. Vlijanie defektov platformennyh stykov na naprjazhenno-deformirovannoe sostojanie konstruktivnyh sistem krupnopanel'nyh zdanij [The influence of defects on the joint platform of the stress- strain state of structural systems of large buildings]. Novosibirsk, 2015. 202 p. Available at: http://search.rsl.ru/en/record/01007955326 (accessed: 10.06.2016). (In Russian).
    9. Tamrazyan A. G., Dudina I. V. Influence of variation of monitored parameters on the reliability of pre-stressed beams at the manufacturing stage. Zhilishhnoe stroitel'stvo, 2001, no. 1, pp. 16-17. (In Russian).
    10. Posobie po proektirovaniju zhilyh zdanij. CNIIJeP zhilishha Goskomarhitektury. Iss. 3. Konstrukcii zhilyh zdanij [Construction of residential buildings] (k SNiP 2.08.01-85). Moscow, Strojizdat Publ., 1989. 304 p. (In Russian).
    11. Tamrazyan A. G., Karpov A. E., Dehterev D. S., Laskovenko A. G. Determination of design parameters for evaluating the reliability of the platform joints of panel buildings. Sovremennye problemy rascheta zhelezobetonnyh konstrukcij, zdanij i sooruzhenij na avarijnye vozdejstvija [Modern problems of calculation of reinforced concrete structures, buildings and structures on the impact of emergency]. Sbornik dokladov Mezhdunar. nauch. konf. (19-20 Apr. 2016, Moscow). Moscow, NIU MGSU, 2016. 528 p. (In Russian).
    12. Moiseenko R. P. Nachal'naja nadjozhnost' jelementov stroitel'nyh konstrukcij [Starting reliability of structural elements]. Tomsk, Izd-vo Tom. gos. arhit.-stroit. un-ta Publ., 2014. 23 p. (In Russian).
    13. Rajzer V. D. Teorija nadezhnosti v stroitel'nom proektirovanii [Theory of reliability in building design]. Moscow, ASV Publ., 1998. 304 p. (In Russian).
    14. Promezhutochnyj otchet na temu: "Razrabotka metodiki rascheta naprjazhenno-deformirovannogo sostojanija i nesushhej sposobnosti 25-jetazhnogo zhilogo krupnopanel'nogo doma tipovoj serii na baze raschetno-jeksperimental'nyh issledovanij" [Development of the method of calculation of stress-strain state and the bearing capacity of a 25- storey residential house large- type series on the basis of settlement and experimental studies ]. Shifr № K.254-14. Moscow, MGSU Publ., 2014. 72 p. (In Russian).
    15. Tehnicheskoe zakljuchenie po rezul'tatam eksperimental'nyh issledovanij prochnosti i deformativnosti panel'nyh stykov [A technical report on the results of experimental studies of the strength and deformability of the panel joints. Moscow, OAO "NIC "Stroitel'stvo" Publ., 2014. 125 p. (In Russian).
  • Limit-State Calculation of Reinforced Concrete Structures with the Use of Probabilistic Method
  • UDC 624.012.45
    Boris S. RASTORGUEV
    Dahi S. VANUS, e-mail: dahiws@gmail.com
    National Research Moscow State University of Civil Engineering, Yaroslavskoe shosse, 26, Moscow 129337, Russian Federation
    Abstract. When designing various objects such as residential and industrial buildings, bridges, damps, offshore platforms etc. it is necessary to envisage all stages of their life cycle. Main parameters on which the process of deformation of the structure depends (loads, physical-mechanical properties of materials) are random values. When calculating the limit state of reinforced concrete structures, random functions are introduced in the field of random parameters of loads and structures. A zero value of the function corresponds to the limit state. In wide used structures (prefabricated in particular), an exit beyond the limit state of individual elements of the system is possible due to the appearance of rare combinations of random parameters. The probabilistic method makes it possible to reveal the influence of such combinations. It is found that among the random parameters, average values of which correspond to the limit state, there are parameters which don't satisfy the limit state as random values. For normal distribution of all these random values, analytical dependences when determining the probability of the system failure are presented with the use of the safety index.
    Key words: reinforced concrete structures, limit-state design, probabilistic method, random values.
  • REFERENCES
    1. Rzhanitsyn A. R. Teoriya rascheta stroitel'nykh konstruktsiy na nadezhnost' [The theory of calculation of building structures on the reliability]. Moscow, Stroyizdat Publ., 1978. 239 p. (In Russian).
    2. Rayzer V. D. Teoriya nadezhnosti v stroitel'nom proektirovanii [Theory of reliability in structural design]. Moscow, ASV Publ., 1998. 304 p. (In Russian).
    3. Rayzer V. D. Teoriya nadezhnosti sooruzheniy [Reliability theory of structures]. Moscow, ASV Publ., 2010. 384 p. (In Russian).
    4. Shpete G. Nadezhnost' nesushchikh stroitel'nykh konstruktsiy [Reliability of bearing structures]. Moscow, Stroyizdat Publ., 1994. 288 p. (In Russian).
    5. Baykov V. N., Sigalov E. E. Zhelezobetonnye konstruktsii [Reinforced concrete structures]. Moscow, Stroyizdat Publ., 1991. 767 p. (In Russian).
    6. Rastorguev B. S., Vanus D. S. Safety assessment of reinforced concrete structures in emergency situations of technogenic character. Stroitel'stvo i rekonstruktsiya, 2014, no. 6 (56), pp. 83-89. (In Russian).
    7. Tamrazyan A. G. Reliability and protection of Moscow mass series from the progressive collapse in case of emergencies of natural and technogenic character. Bezopasnost' zhiznedeyatel'nosti, 2002, no. 1, pp. 35-38. (In Russian).
    8. Tamrazyan A. G. On the calculation of reinforced concrete elements with due regard for creep and aging onthe basis of rheological model of concrete. Promyshlennoe i grazhdanskoe stroitel'stvo, 2012, no. 7, pp. 26-27. (In Russian).
    9. Shumilov K. A., Kozlova E. M. Veroyatnostnye metody v stroitel'noy mekhanike [Probabilistic methods in structural mechanics]. St. Petersburg, SPb GASU. 2015. 64 p. (In Russian).
    10. Sorensen J. D. Structural reliability theory and risk analysis. Institute of Building Technology and Structural Engineering Aalborg University Sohngaardsholmsvej 57, DK-9000 Aalborg, Denmark, 2004. 217 p.
  • Strength and Deformability of Masonry under Biaxial Stress State
  • UDC 624.012.2:624.042
    Oleg V. KABANTSEV, e-mail: ovk531@gmail.com
    National Research Moscow State University of Civil Engineering, Yaroslavskoe shosse, 26, Moscow 129337, Russian Federation
    Abstract. The paper provides the analysis of experimental study results of the elastic-plastic deformation and destruction of the masonry under conditions of biaxial stress state. The principle of simulating the masonry as a patch-homogeneous different-module composite is substantiated; this makes it possible to develop the structural model of the masonry. Various mechanisms of the formation of local masonry failure under the increasing load including basic materials (brick and mortar) and joints of their contact interaction are considered. The system of strength criteria corresponding to established mechanisms of local failures is proposed. On the basis of he analysis of results of numerical studies it is established that a key parameter, which determines both the strength and deformability of masonry, including plastic phase, is the strength of the adhesion interaction of basic materials in the masonry joints. The sequence of the formation of local failures of different types has been determined. The most important mechanisms of local failures, which cause the process of plastic deformation of the masonry, have been revealed. On the basis of the study results, values of coefficients of masonry plasticity have been obtained.
    Key words: masonry, brick, mortar, stress-strain state, modeling, calculation model, numerical methods.
  • REFERENCES
    1. Geniev G. A. On the criteria of strength of masonry in a plane stress state. Stroitel'naya mekhanika i raschet sooruzheniy, 1979, no. 2, pp. 7-11. (In Russian).
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    3. Polyakov S. V., Safargaliev S. M. Monolitnost' kamennoy kladki [The solidity of the masonry]. Alma-Ata, Gylym Publ., 1991. 160 p. (In Russian).
    4. Burago N. G. Simulation of damage of elastoplastic bodies. Vychislitel'naya mekhanika sploshnykh sred, 2008, vol.1, no. 4, pp. 5-20. (In Russian).
    5. Vil'deman V. E., Sokolkin Yu. V., Tashkinov A. A. Mekhanika neuprugogo deformirovaniya i razrusheniya kompozitsionnykh materialov [Mechanics of inelastic deformation and fracture of composite materials]. Moscow, Nauka Publ., 1997. 228 p. (In Russian).
    6. Trusov P. V. Some questions of nonlinear mechanics of deformable solids (in order of discussion). PNRPU Mechanics Bulletin, 2009, no. 17, pp. 85-95. (In Russian).
    7. Il'yushin A. A. Mekhanika sploshnoy sredy [Continuum mechanics]. Moscow, Moskow St. Univ. Publ., 1978, 287 p. (In Russian).
    8. Parton V. Z., Morozov E. M. Mekhanika uprugoplasticheskogo razrusheniya. Osnovy mekhaniki razrusheniya [Mechanics of elastic-plastic fracture. Fundamentals of fracture mechanics]. Moscow, LKI Publ., 2008. 352 p. (In Russian).
    9. Kabantsev O. V. A discrete model of masonry under conditions of biaxial stress state. Vestnik of TSUAB, 2015, no. 4, pp.113-134. (In Russian).
    10. Kabantsev O. V., Tamrazyan A. G. Modeling of elastic-plastic deformation of masonry under conditions of biaxial stress state. International Journal for Computational Civil and Structural Engineering, 2015, iss. 3, vol. 11, pp. 87-100. (In Russian).
    11. Kopanitsa D. G., Kabantsev O. V., Useinov E. S. Experimental studies of fragments of masonry on the static and dynamic loads. Vestnik of TSUAB, 2012, no. 4, pp. 157-178. (In Russian).
    12. Tonkikh G. P., Kabantsev O. V., Simakov O. A., Simakov A. B., Baev S. M., Panfilov P. S. Experimental study of seismic strengthening of masonry exterior concrete applications. Seysmostoykoe stroitel'stvo. Bezopasnost' sooruzheniy, 2011, no. 2, pp. 35-42. (In Russian).
    13. Kashevarova G. G., Zobacheva A. Yu. Modeling of process of destruction of brickwork. PNRPU Construction and Architecture Bulletin, 2010, no. 1, pp. 106-116. (In Russian).
    14. Pangaev V. V., Albaut G. I. , Fedorov A. V., Tabanyukhova M. V. Simulation studies of the stress-strain state of masonry in compression. Izvestia vuzov. Stroitel'stvo, 2003, no. 2, pp. 24-29. (In Russian).
    15. Sokolov B. S., Antakov A. B. The research results of masonry and reinforced masonry. Vestnik MGSU, 2014, no. 3, pp. 99-106. (In Russian).
    16. Ademoviг N., Hrasnica M. Capacity degradation and crack pattern development in a multi-storey unreinforced masonry building. Gradjevinar, 2015, no. 67 (4), pp. 351-361.
    17. Capozucca R. Shear behaviour of historic masonry made of clay bricks. The Open Construction and Building Technology Journal, 2011, no. 5. (Suppl 1-M6), pp. 89-96.
    18. Grishchenko A. I., Semenov A. S., Semenov S. G., Melnikov B. E. Influence of structural parameters of the masonry on effective elastic properties and strength. Inzhenerno-stroitel'nyy zhurnal, 2014, no. 5, pp. 95-106.
    19. Mohebkhah A., Tasnimi A. A. Distinct element modeling of masonry-infilled steel frames with openings. The Open Construction and Building Technology Journal, 2012, no. 6 (Suppl 1-M2), pp. 42-49.
    20. Schubert P., Bohene D. Schubfestigkeit von Mauerwerk aus Leichtbetonsteinen. Das Mauerwerk. 2002, heft 3, pp. 98-102.
    21. Kabantsev O. V., Tamrazyan A. G. Changes in the calculated scheme during the analysis of design. Inzhenerno-stroitel'nyy zhurnal, 2014, no. 5, pp. 15-26. (In Russian).
    22. Kabantsev O. V., Perel'muter A. V. Accounting for changes in stiffness of the elements in the process of installation and operation. Inzhenerno-stroitel'nyy zhurnal, 2015, no. 5, pp. 6-14. (In Russian).
    23. Karpilovskiy V. S., Kriksunov E. Z., Malyarenko A. A., Mikitarenko M. A., Perel'muter A. V., Perel'muter M. A. SCAD Office. Versiya 21. Vychislitel'nyy kompleks SCAD++ [SCAD Office. Version 21. Computing complex SCAD++] Moscow, SKAD SOFT Publ., 2015. 808 p. (In Russian).
    24. Kabantsev O. V. Deformation properties of masonry as a heterogeneous piecewise-homogeneous medium. Seysmostoykoe stroitel'stvo. Bezopasnost' sooruzheniy, 2013, no. 4, pp. 36-40. (In Russian).
    25. Popov N. N., Rastorguev B. S. Dinamicheskiy raschet zhelezobetonnykh konstruktsiy [Dynamic analysis of reinforced concrete structures]. Moscow, Stroyizdat Publ., 1974. 207 p. (In Russian).
  • To Assessing the Reliability Reinforced Concrete Flat Slabs for Punching under the Action of Concentrated Force at High Temperatures
  • UDC 624.012.45+624.073
    Ashot G. TAMRAZYAN, e-mail: tamrazian@mail.ru
    Yury N. ZVONOV, e-mail: gss416@mail.ru
    National Research Moscow State University of Civil Engineering, Yaroslavskoe shosse, 26, Moscow 129337, Russian Federation
    Abstract. Authors have considered one of the perspective innovative approaches to the calculation of reinforced concrete elements of buildings and constructions on punching with use of the theory of reliability under conditions of beyond design basis impact. On the basis of the determined decision, it is shown that methods of mathematical statistics and probability theory when calculating on punching from the concentrated force of reinforced concrete flat slabs without cross reinforcement under the impact of high temperatures, in particular in the conditions of the fire, taking into account variability of fire effect and variability of warming up of concrete by height of section of an element and fittings make it possible to reliably determine the probability of emergence of refusal of an element of a design of buildings and constructions. The authors consider the change in properties of concrete under the influence of high temperatures. The method of calculation of the reliability of floor slabs for punching under fire conditions with due regard for its stochastic character is presented. It is shown that the accounting of variability of strength properties of concrete under conditions of high temperatures, and also variability of temperature conditions of the fire leads to the increased probability of failure of reinforced concrete slabs on punching. The authors draw a conclusion that the existing technique of calculations of slabs on punching under conditions of the fire on the basis of private stock coefficients doesn't ensure the trouble-free operation of the construction.
    Key words: reinforced concrete slab, punching, fire impacts, fire resistance, standard temperature regime of fire, variability of temperature regime of fire, failure probability, reliability.
  • REFERENCES
    1. Rzhanitsyn A. R. Teoriya rascheta stroitel'nykh konstruktsiy na nadezhnost' [The theory of calculation of building constructions on reliability]. Moscow, Stroyizdat Publ., 1978. 239 p. (In Russian).
    2. Tamrazyan A. G., Zvonov Y. N. To an assessment of reliability of the bent reinforced concrete plates at fire influences. Scientific review, 2015, no. 14, pp. 130-133. (In Russian).
    3. Duc Toan Pham, Patrik de Buhan, Celine Florence, Jean-Vivien Heck, Hohg Hai Nguyen. Interaction diagrams of reinforced concrete sections in fire. A yield design approach. Engineering Structures, 2015, vol. 90, pp. 38-47.
    4. Tamrazyan A. G., Avetisyan L. A. Experimental research in eccentrically compressed reinforced concrete elements during short-term dynamic loadings under fire conditions. Promyshlennoe i grazhdanskoe stroitel'stvo, 2014, no. 4, pp. 24-28. (In Russian).
    5. Tamrazyan A. G., Mekhralizadekh A. B. Features of manifestation of fire impacts when calculating designs on the progressing destruction of buildings with transitional floors. Fire and explosion safety, 2012, no. 12, pp. 41-44. (In Russian).
    6. Tamrazyan A. G. Reduce the impact of dynamic strength of concrete under fire conditions on bearing capacity of reinforced concrete columns. ICSMIM 2013. 2nd International conference on sensors, measurement and intelligent materials. Guangzhou, China, Nov. 16-17, 2013. Pp. 1563-1566.
    7. Gmurman V. E. Teoriya veroyatnostey i matematicheskaya statistika [Probability theory and mathematical statistics], Moscow, Yurayt Publ., 2015. 479 p. (In Russian).
    8. Anderberger Y., Thelandersson S. Stress and deformation characteristics of concrete at high temperatures. Experimental investigation and material behavior model. Lund Institute of Technology, Sweden, 1976, bull. 54, 84 p.
    9. Bolgov A. N., Sokurov A. Z. Numerical modeling of punching flat slabs strengthened by shear reinforcement. "Beton i zhelezobeton - vzglyad v budushchee". Nauch. tr. III Vserossiyskoy (II Mezhdunarodnoy) konferentsii po betonu i zhelezobetonu. ["Concrete and reinforced concrete - cleance at future". Scientific works of the III All Russian (II International) conference on concrete and reinforced concrete: in 7 vol.]. Moscow, MGSU Publ., 2014. Vol. 4. Pp. 139-149. (In Russian).
    10. Filatov V. B. Power resistance of reinforced concrete monolithic flat plates of overlappings at breakdown by columns of rectangular section. News of the Samara scientific center of the Russian Academy of Sciences, 2012, no. 4-5, pp. 1322-1324. (In Russian).
    11. Krasnoshchekov Y. V., Komlev A. A. Experimental check of durability of flat plates of overlappings on breakdown. 64-ya nauch.-tekhn. konf. GOU "SibADI" v ramkakh yubileynogo mezhdunarodnogo kongressa "Kreativnye podkhody v obrazovatel'noy, nauchnoy i proizvodstvennoy deyatel'nosti", posvyashchennogo 80-letiyu akademii [The 64th scientific and technical conference of SIBADI Public Educational Institution within the anniversary international congress "Creative approaches in an educational, scientific and production activity" devoted to the 80 anniversary of academy]. Omsk, SibADI Publ., 2010, pp. 219-222. (In Russian).
  • Effect of Non-Bearing Structures on Dynamic Parameters of Frame Buildings and Structures under Low-Intensity Loads
  • UDC 624.016.5:624.042.7
    Gennady P. TONKIKH, e-mail: 5059144@mail.ru
    National Research Moscow State University of Civil Engineering, Yaroslavskoe shosse, 26, Moscow 129337, Russian Federation
    Abstract. This article describes the basic modeling principles that must be followed during the tests on models made of different materials. As an example, the results of tests on the model of the 3-story frame-panel barrack building made of plexiglas and intended for the use in seismically active regions with earthquake intensity of 7-9 points. The standard series was used for the barracks design. The tests were carried out to assess the influence of curtain walls on the frequency characteristics of the building under the action of low-intensity dynamic loads. On the basis of studies conducted and obtained dependencies of change in the self-oscillations of the frame building model, it is proposed to us to use the influence coefficient кв for assessing the influence of non-bearing structures during the field tests of frame buildings with impacts of low intensity. Values of this coefficient are selected depending on the actual filling with non-bearing structures (the number of partitions, their location in the plan and on the floors), as well as on the availability of curtain wall panels. On the basis of the test conducted, it is established that depending on the filling with non-bearing structures the coefficient кв almost doubles.
    Key words: modeling, frame buildings, self-oscillation period, non-bearing structures, low-intensive dynamic loads.
  • REFERENCES
    1. Karpatskoe zemletryasenie 1986 g. [The Carpathian earthquake of 1986]. Pod red. A. V. Drumya, N. V. Shebalina, N. N. Skladneva, S. S. Grafova, V. I. Oyzermana. Kishenev, 1990. 334 p. (In Russian).
    2. Tikhonov I. N., Shevchenko G. V. Shikotanskoe zemletryasenie i tsunami 4(5) oktyabrya 1994 g. Khronika sobytiy, analiz posledstviy i sovremennoe sostoyanie problemy [Shikatanai earthquake and tsunami, 4(5) Oct 1994. Chronicle of events, evaluation of impacts, and current state of the problem]. Yuzhno-Sakhalinsk, Institut morskoy geologii i geofiziki Dal'nevostochnogo otdeleniya RAN Publ., 2014. 114 p. (In Russian).
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    4. Tarasov A. M. Opredelenie kriteriev podobiya i perekhodnykh sootnosheniy pri modelirovanii mostovykh konstruktsiy [Definition of criteria of similarity and transition ratios in modeling bridge structures]. Trudy TsNIIS. Moscow, 1974, no. 80, 64 p. (In Russian).
    5. Tonkikh G. P., Kabantsev O. V., Dorofeev M. L. Posobie po uchetu vliyaniya nenesushchikh konstruktsiy na dinamicheskie kharakteristiki obshchevoyskovykh karkasnykh zdaniy pri otsenke ikh seysmostoykosti [The manual on account of the influence of curtain designs on the dynamic characteristics of the combined frame buildings to assess their seismic resistance]. Moscow, 26 TsNII MO RF Publ., 2004. 43 p. (In Russian).
    6. Tonkikh G. P., Kabantsev O. V., Dorofeev M. L. Experimental study of the influence of nonconstructive elements on periods of oscillation of frame buildings. Seysmostoykoe stroitel'stvo. Bezopasnost' sooruzheniy, 2002, no. 6, pp. 12-16. (In Russian).
    7. Tonkikh G. P. Modelirovanie zdaniy i sooruzheniy pri provedenii ispytaniy na malointensivnye dinamicheskie nagruzki [Modeling of buildings and structures when carrying out tests on low-intensity dynamic loads]. Sb. dokl., posvyashchennykh 100-letiyu N. N. Popova. Moscow, MGSU Publ., 2016. Pp. 440-445. (In Russian).
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  • Optimal Design of Reinforced Concrete Floor Slabs According to the Criterion of Minimum Cost
  • UDC 624.073.4
    Ashot G. TAMRAZYAN, e-mail: tamrazian@mail.ru
    Ekaterina A. FILIMONOVA, e-mail: FilimonovaEA@mgsu.ru
    National Research Moscow State University of Civil Engineering, Yaroslavskoe shosse, 26, Moscow 129337, Russian Federation
    Abstract. Traditional design methods of reinforced concrete floor slabs with due regard for the risk analysis necessitate to significant increase the material stock. The purpose of optimization of reinforced concrete slabs is to find a rational solution which would meet such main requirements as strength, reliability, safety. That's why in the tasks of optimal design of structures a certain target function is formed together with the requirement to minimize or maximize it and complex of requirements with due regard for efficiency and manufacturability, operating costs and risks as well as limitations on material and labor resources. The most common optimality criterion is the minimum cost. The method for calculation and optimization of building structures can be significantly improved by increasing the use of risk analysis. The magnitude of the risk of structural systems, which are under the influence of outside forces, is determined by the magnitude of the destruction of structures and responsibility of structures. The use of probabilistic apparatus makes it possible to quantitatively determine the safety level of structures and the use of search algorithms - to design them according to the criterion of minimum cost. When choosing search optimization techniques, the imperative requirement is simultaneous account of changes in the target function and boundary conditions in the course of moving towards the optimum. The algorithm based on the method of random search meets this requirement. The proposed improved search technique makes it possible to assuredly solve the problem of the optimizing choice of parameters of structures, both with the non-linear constraints and with a non-linear target function.
    Key words: target function, search optimization, reinforced concrete slab, criterion of minimum cost, risk, failure probability, damage.
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    6. Tamrazyan A. G., Filimonova E. A. Criteria for the formation of a complex objective function reinforced concrete slab with risk analysis. Vestnik MGSU, 2013, no. 10, pp. 68-74. (In Russian).
    7. Lychev A. S. Nadezhnost' stroitel'nykh konstruktsiy [Reliability of building structures]. Moscow, ASV Publ., 2008. 184 p. (In Russian).
    8. Pichugin S. F., Semko A. V., Makhin'ko A. V. Determination of the safety factor for the purpose considering the risks in construction. Izvestiya vuzov. Stroitel'stvo, 2005, no. 11-12, pp. 104-109. (In Russian).
    9. Laptin U. P. One approach to solving nonlinear constrained optimization problems. Cybernetics and Systems Analysis, 2009, no. 3, pp. 182-187.
    10. Tamrazyan A. G., Filimonova E. A. Optimization concrete slabs on the criterion of minimum cost with risk analysis. Promyshlennoe i grazhdanskoe stroitel'stvo, 2014, no. 9, pp. 19-22. (In Russian).
    11. Rastorguev B. S., Mutoka K. N. Deformation structures overlap frame buildings after the sudden destruction of one column. Seysmostoykoe stroitel'stvo. Bezopasnost' sooruzheniy, 2006, no. 1, pp. 12-15. (In Russian).
    12. Rastorguev B. S. Methods for calculating the stability of buildings against progressive collapse. Vestnik Otdeleniya stroitel'nykh nauk Rossiyskoy akademii arkhitektury i stroitel'nykh nauk, 2009, no. 13, pp. 15-20. (In Russian).
    13. Dinamicheskiy raschet spetsial'nykh inzhenernykh sooruzheniy i konstruktsiy [Dynamic calculation of special engineering structures and constructions]. Spravochnik proektirovshchika. Moscow, Stroyizdat Publ.,1986. (In Russian).
    14. Rastorguev B. S., Plotnikov A. I. Calculation of load-bearing structures of reinforced concrete monolithic buildings in the progressive destruction considering dynamic effects. Sbornik nauchnykh trudov Instituta stroitel'stva i arkhitektury MGSU. Moscow, 2008, iss. 1, pp. 68-75. (In Russian).
    15. Filimonova E. A. Method of searching optimal parameters of reinforced concrete structures with risk of failure. Vestnik MGSU, 2012, no. 10, pp. 128-133. (In Russian).
  • BUILDING STRUCTURES, BUILDINGS AND FACILITIES
  • On Calculation of Concrete Flexural Elements with Indirect Reinforcement of a Compressed Zone
  • UDC 624.012.45
    Ashot G. TAMRAZYAN, e-mail: tamrazian@mail.ru
    Ivan K. MANAENKOV, e-mail: manaenkov.i.k@gmail.com
    National Research Moscow State University of Civil Engineering, Yaroslavskoe shosse, 26, Moscow 129337, Russian Federation
    Abstract. At present, engineering solutions improving the structures made of traditional material are widely applied. For this reason, reducing the cost of construction is closely connected with the improvement of reinforced concrete structures which are the basis of capital construction in most countries of the world. In the contemporary design, there is a tendency to use structures and methods of calculation providing a choice of rational and cost effective design solutions. Indirect reinforcement is one of the ways to improve the strength and deformation characteristics of concrete by limiting transverse strains and creating the volumetric stress state in the amplification zone. The article describes the features of work of flexural concrete elements with indirect reinforcement of the compressed zone. It shows the physical meaning of the boundary relative height of the compressed zone of flexural concrete elements. An example of the most used frames with indirect reinforcement in the form of welded grids is given. On the basis of conducted studies, factors which determine the height of the compressed zone for beams with indirect reinforcement are revealed. The article highlights the difficulties in determining the fracture mechanism of concrete flexural elements with indirect reinforcement of the compressed zone and identifies the ways of carrying out further experimental and theoretical studies.
    Key words: reinforced concrete flexural element, boundary relative height of compressed zone, indirect reinforcement, confined concrete, ultimate compressibility.
  • REFERENCES
    1. Tamrazyan A. G., Manaenkov I. K. On the calculation of flat ferroconcrete floors with the consideration of the actual rigidity of section. Nauchnoe obozrenie, 2015, no 8. pp. 87-92. (In Russian).
    2. Krishan A. L., Rimshin V. I., Zaikin A. I. Calculation of the strength of compressed reinforced concrete elements with indirect reinforcement. "Beton i zhelezobeton - vzgljad v budushhee". Nauchnye trudy III Vserossijskoj (II Mezhdunarodnoy) konferencii po betonu i zhelezobetonu ["Concrete and reinforced concrete - glance at future". Scientific papers of the III all-Russian (II International) conference on concrete and reinforced concrete]. Moscow, MGSU Publ., 2014. Vol. 1. Teorija zhelezobetona. Zhelezobetonnye konstrukcii. Raschet i konstruirovanie, pp. 308-313. (In Russian).
    3. Jarkin R. A., Anisimov S. V., Strulev V. M. Theoretical bases of application of lateral reinforcement in flexural reinforced concrete elements. Proc. Tambovskogo gos. techn. unt-ta, iss. 10. Tambov, TGTU Publ., 2001, pp. 74-78. (In Russian).
    4. Rastorguev B. S., Vanus D. S. Calculation of bent reinforced-concrete elements with indirect reinforcement mesh compression zone. Promyshlennoe i grazhdanskoe stroitel'stvo, 2010, no. 12, pp. 58-60. (In Russian).
    5. Rastorguev B. S, Jakovlev S. K. On the question of the application of indirect reinforcement in girders of multi-storey industrial buildings. Izvestiya vuzov. Stroitel'stvo i arhitektura, 1985, no. 9. pp. 1-4. (In Russian).
    6. Zhaoynan Chen, Zihao Wang, Qingin Zhao. Use of hich-strength concrete in blast-resistand structures. Tsinghua university, Beising, China. 1992. 138 p.
    7. Grinev V. D., Belevich S. D. Work with reinforced concrete beams condensed area. Promyshlennoe i grazhdanskoe stroitel'stvo, 1993, no. 10, p. 12. (In Russian).
    8. Bajkov V. N., Sigalov Je. E. Zhelezobetonnye konstrukcii. Obshhij kurs [Reinforced concrete structures. General course]. Moscow, Strojizdat Publ., 1991. 761 p. (In Russian).
    9. Vasil'ev A. P., Matkov N. G., Filippov B. N. Durability and deformation struts with indirect reinforcement. Beton i zhelezobeton, 1973, no. 4, pp. 16-26. (In Russian).
    10. Shahvorostov A. I. Povyshenie jeffektivnosti zhelezobetonnyh jelementov s kosvennym armirovaniem za schet ispol'zovanija betonov na rasshirjajushhemsja vjazhushhem. Sb. materialov vserossijskoj nauchno-prakticheskoj konferencii molodyh uchenyh "Stroitel'nye konstrukcii - 2000" [The collection of materials of all-Russian scientific.-practical conference of young scientists "Building construction - 2000"]. Moscow, MGSU Publ., 2000. Part. 1. Zhelezobetonnye i kamennye konstrukcii. pp. 118-123. (In Russian).
  • Bearing Capacity of Elements of Masonry Reinforced with Steel-Fiber Concrete Casings
  • UDC 624.012.2
    Anatoly I. BEDOV, e-mail: mgsu@gbk.ru
    National Research Moscow State University of Civil Engineering, Yaroslavskoe shosse, 26, Moscow 129337, Russian Federation
    Abstract. The method for assessment of bearing capacity of centrally compressed brickwork elements reinforced by the steel-fiber casing is described. The equation of surface limiting the area of masonry resistance under conditions of 3-axial stress-strain state is presented; by its conversion a formula for determining the bearing capacity of a compressed element included in the casing has been obtained. Results of the analysis of assessment of the bearing capacity of brickwork element without damages enforced by the casing reinforced with steel fiber and rod reinforcement (combined reinforcement) as well as by the casing reinforced with steel fiber only are presented. Comparison of values of bearing capacities of these two types of casing shows that for the combined casing it is higher by 45% at the factor of reinforcement with fiber of 2% in comparison with the reinforced concrete casing. At reinforcement of the casing with fiber only at the minimal percentage of fiber reinforcement, the bearing capacity of the element is higher than for the usual reinforced concrete one. An analysis of the stress-strain state of the brickwork included in the casing with the use of ANSYS 14.0, was made; it showed a good similarity with the results obtained according to the proposed method.
    Key words: masonry, strengthening of masonry structures, casing, steel fiber concrete, bearing capacity, stress-strain state.
  • REFERENCES
    1. Tonkih G. P., Kabantsev O. V., Granovskij A. V., at el. Experimental study of seismic strengthening of masonry system of external reinforcement based on carbon fiber. Vestnik of TSUAB, 2014, no. 6 (47), pp. 57-69. (In Russian).
    2. Ivlev M. A. Konstruktivnye osobennosti fibrobetonnyh peremychek sten zdanija [Design features fiber jumpers the walls of the building]. Diss. kand. tehn. nauk. Ufa, 2013. 260 p. Available at: http://www.dslib.net/stroj-konstrukcii/konstruktivnye-osobennosti-fibrobetonnyh-peremychek-sten-zdanij.html (accessed 10.05.2016).
    3. Gasiev A. A., Granovskij A. V. To the question of evaluation of load-bearing capacity of brick piers reinforced with sheets of carbon-fiber fabric under the action of shearing loads. Promyshlennoe i grazhdanskoe stroitel'stvo, 2015, no. 6, pp. 36-42. (In Russian).
    4. Geniev G. A., Kissjuk V. N., Tjupin G. A. Teorija plastichnosti betona i zhelezobetona [Theory of plasticity of concrete and reinforced concrete]. Moscow, Stroyizdat Publ., 1974. 316 p. (In Russian).
    5. Kabantsev O. V. Particular criteria of strength of masonry for the analysis of elastic-plastic deformation. Sejsmostojkoe stroitel'stvo. Bezopasnost' sooruzhenij, 2013, no. 3, pp. 36-41. (In Russian).
    6. Kabantsev O. V., Tamrazyan A. G. Uchet izmenenij raschetnoj shemy pri analize raboty konstrukcii. Inzhenerno-stroitel'nyj zhurnal, 2014, no. 5 (49), pp. 15-26. (In Russian).
    7. Posobie po proektirovaniju kamennyh i armokamennyh konstrukcij (k SNiP II-22-81* "Kamennye i armokamennye konstrukcii. Normy proektirovanija") [A manual for design of masonry and reinforced masonry structures (to SNiP II-22-81* "Stone and reinforced masonry structures. Design standards"]. Moscow, CITP Gosstroja SSSR Publ., 1989. 152 p. (In Russian).
    8. Terjanik V. V. Some results of the study strengthening of eccentrically compressed reinforced concrete elements clips. Izvestija vuzov. Stroitel'stvo. 2001, no. 8, pp. 146-149. (In Russian).
    9. ANSYS Mechanical 11.0 User`s guide. Constitutive model for the triaxial behavior of concrete. Proc. of the International Association for Bridge and Structural Engineering. Italy, ISMES, Bergamo, 1975. 174 p.
  • Behavior of Statically Indeterminable Reinforced Concrete Members under Negative Temperatures
  • UDC 624.142:624.012.45
    Andrey D. ISTOMIN, e-mail: nauka.07@mail.ru
    Alexandr V. KUDRYAVTSEV, e-mail: alexandrkav@mail.ru
    National Research Moscow State University of Civil Engineering, Yaroslavskoe shosse, 26, Moscow 129337, Russian Federation
    Abstract. In the course of construction of buildings in regions with complex temperature-humidity terms it is necessary to provide the durability, reliability and efficiency of operating reinforced concrete structures. Till present time, statically indeterminable structures, in which forced efforts arise due to the discrepancy between the operational temperature and temperature of shorting, remain little studied. In this connection the experimental study of behavior of such reinforced concrete members at joint power and low-temperature loading is very important. On the basis of results of the conducted experiments on research in behavior of concrete at negative temperatures, dependences for the coefficient of temperature deformations, module of concrete elasticity depending on the temperature of freezing and humidity have been obtained. Formulas for determining the rigidity of reinforced concrete elements working at negative temperatures are presented. It is established that when determining the rigidity of reinforced concrete members under negative temperatures, forces arising due to the difference of coefficients of linear thermal deformations of concrete and reinforcement play a significant role.
    Key words: temperature, humidity, deformations, module of deformations, statically indeterminable constructions, rigidity, efforts.
  • REFERENCES
    1. Tamrazyan A. G. Concrete and reinforced concrete: problems and prospects. Promyshlennoe i grazhdanskoe stroitel'stvo, 2014, no. 8, pp. 30-33. (In Russian).
    2. Kurnavina S. O. Cyclic bending of reinforced concrete structures based on elastic-plastic deformations of reinforcement and concrete. Vestnik MGSU, 2010, no. 2, vol. 1, pp. 154-158. (In Russian).
    3. Almazov V. O., Istomin A. D. Influence of the water saturation on temperature deformation of concrete under freezing. Vozdeystviya vneshnikh faktorov na gidrotekhnic heskie sooruzheniya [The effects of external factors on hydrotechnical structures]. Moscow, MISI Publ., 1986. Pp. 162-169. (In Russian).
    4. Moskvin V. M., Kapkin M. M., Savitskiy A. N., Yarmakovskiy V. N. Beton dlya stroitel'stva v surovykh klimaticheskikh usloviyakh [Concrete construction in extreme climatic conditions]. Leningrad, Stroyizdat Publ., 1973. 172 p. (In Russian).
    5. Milovanov A. F. Raschet zharostoykikh zhelezobetonnykh konstruktsiy [Design of heat-resistant reinforced concrete structures]. Moscow, Stroyizdat Publ., 1975. 232 p. (In Russian).
    6. Rzhanitsyn A. R. Stroitel'naya mekhanika [Structural mechanics]. Moscow, Vysshaya shkola Publ., 1982. 400 p. (In Russian).
    7. Posobie po proektirovaniyu betonnykh i zhelezobetonnykh konstruktsiy bez predvaritel'nogo napryazheniya armatury (k SP 52-101-2003) [Manual for the design of concrete and reinforced concrete without rebar voltage (to SP 52-101-2003)] Moscow, FGUP TsPP Publ., 2005. 151 p. (In Russian).
    8. Zalesov A. S., Kodysh E. N., Lemysh L. L., Nikitin I. N. Raschet zhelezobetonnykh konstruktsiy po prochnosti, treshchinostoykosti i deformatsiyam [Design of reinforced concrete structures for strength, fracture toughness and deformation]. Moscow, Stroyizdat Publ., 1988. 320 p. (In Russian).
    9. Murashev V. I. Treshchinoustoychivost', zhestkost' i prochnost' zhelezobetona [Crack resistance, stiffness and strength of the concrete]. Moscow, Mashstroyizdat, 1950. 136 p. (In Russian).
    10. Suslov Yu. A. Stiffness research of conventional and prestressed bent concrete members. Zhelezobetonnye konstruktsii i krupnye paneli [Reinforced concrete structures and large panels]. Moscow, Vysshaya shkola Publ., 1966. Pp. 110-119. (In Russian).
    11. Almazov V. O., Istomin A. D. Temperature efforts in the reinforced concrete structures of marine hydraulic structures. Morskie neftegazopromyslovye sooruzheniya [The offshore oil and gas facilities]. Riga, VNIImorgeo Publ., 1989. Pp. 104-110. (In Russian).
  • Strength and Bearing Capacity of Compressed Reinforced Concrete Elements under Dynamic Loading at High Temperatures
  • UDC 624.012.45.042.5
    Ashot G. TAMRAZYAN, e-mail: tamrazian@mail.ru
    Levon A. AVETISYAN, e-mail: avetisyanlevon@inbox.ru
    National Research Moscow State University of Civil Engineering, Yaroslavskoe shosse, 26, Moscow 129337, Russian Federation
    Abstract. The article presents the results of dynamic calculation of an eccentrically compressed reinforced concrete column under different temperatures of the fire, which show that the dynamic strength of the column is greatly reduced compared to the static one. The transition from one working stage of the element to another one under the dynamic loading occurs faster. The time of transition from the elastic to elastic-plastic stage under the fire impact is 1.32 times less than after cooling. For calculation case, the opening angle of plastic hinge of the reinforced concrete column after cooling is 1.35 times less than he opening angle of plasticity under fire effects. Results of the non-linear dynamic calculation of the reinforced concrete frame at elevated temperatures with the help of opening angle of plastic hinge in bearing members of the frame are presented.
    Key words: reinforced concrete column, fire effect, dynamic loading, coefficient of dynamic strengthening, eccentricity.
  • REFERENCES
    1. Kurlapov D. V. Exposure high temperatures of fire on building structures. Inzhenerno-stroitel'nyj zhurnal, 2009, no. 4, pp. 41-43. (In Russian).
    2. Milovanov A. F., Solomonov V. V., Kuznecova I. S. Fire and Ognissanti of buildings and structures. Promyshlennoe i grazhdanskoe stroitel'stvo, 2002, no. 9, pp. 39-40. (In Russian).
    3. Mindeguia J. C., Carrй H., Pimienta P. & La Borderie C. Nouvelle technique de mesure des dйformation sradiales du bйton а hautes tempйratures. In Rencontres Universitaires de Gйnie Civil. La Grande Motte. June 1-2 2006, pp. 44-49.
    4. Tamrazyan A. G. To assess the risk of emergencies on the main features of its manifestation in the construction. Beton i zhelezobeton, 2001, no. 5, p. 8. (In Russian).
    5. Tamrazyan A. G. Features the work of high-rise buildings. Zhilishhnoe stroitel'stvo, 2004, no. 3, pp. 19-20. (In Russian).
    6. Madatyan S. A. Diagram of stretching of the reinforcement and the bearing capacity of reinforced concrete structures. Beton i zhelezobeton, 1985, no. 5, pp.12-13. (In Russian).
    7. Tamrazyan A. G., Avetisjan L. A. Dynamic calculation of compressed reinforced concrete elements taking into account the effects of fire. Svidetel'stvo o gosudarstvennoj registracii programmy dlja JeVM no. 2015615847. (In Russian).
    8. Tamrazyan A. G., Avetisjan L. A. The calculation of eccentrically compressed reinforced concrete elements for transient dynamic load. Stroitel'stvo: nauka i obrazovanie, 2013, no. 4, p. 2. (In Russian).
    9. Tamrazyan A. G., Avetisjan L. A. To account of the dynamic hardening factor in the calculation of reinforced concrete columns under fire effects. Vestnik Irkutskogo gosudarstvennogo tehnicheskogo universiteta, 2014, no. 9 (92), pp. 133-138. (In Russian).
    10. Tamrazyan A. G., Avetisyan L. A. Estimation of load bearing capacity of eccentrically compressed reinforced concrete elements under dynamic loading in fire conditions. Applied Mechanics and Materials, 2014, vol. 638-640, pp. 62-65.
    11. Tamrazyan A. G. Reduce the impact of dynamic strength of concrete under fire conditions on bearing capacity of reinforced concrete columns. ICSMIM 2013. 2nd International Conference on Sensors, Measurement and Intelligent Materials. Guangzhou, China, November 16-17, 2014, vol. 475-476, pp. 1563-1566.
    12. Mamin A. N. Primenenie metoda diskretnyh svjazej pri nelinejnyh raschetah zhelezobetonnyh konstrukcij. Promyshlennoe i grazhdanskoe stroitel'stvo, 2004, no. 6, pp. 27-28. (In Russian).
    13. Kokot S., Anthoine A., Negro P. and Solomos G. Static and dynamic analysis of a reinforced concrete flat slab frame building for progressive collapse. Engineering Structures, 2012, no. 40, pp. 205-217.
    14. Li yi, Lu Xingzheng, Li yi. Design method to resist progressive collapse for a three story RC frame. Journal of PLA University of Science and Technology, 2007, no. 8(6), pp. 659-664.
    15. Lie T. T., Lin T. D., Allen D. E., Abrams M. S. Fire resistance of Reinforced Concrete Columns. National research council Canada division of building research. Journal of Fire Protection Engineering, 1984, no. 5, pp. 53-59.
  • Calculation of Plate-Stem Reinforced Concrete Trusses According to the Second Group of Limit States
  • UDC 624.074.1
    Alexander N. TOPILIN, e-mail: alex-topilin@mail.ru
    National Research Moscow State University of Civil Engineering, Yaroslavskoe shosse, 26, Moscow 129337, Russian Federation
    Absract. Plate-stem trusses consist of plate elements capable to work in bending out of structures plane and can be designed in two types. In one of them all elements have the plate configuration; in another one, a part of elements (stretched) can be linear-stem. A method for calculation of a plate-stem truss according to deformations caused by bending and torque moments is presented; this method is based on using known laws of physics and material resistance that improves its reliability. A solution of very difficult problem of determining the torsion angle of the truss at the stage after cracking of its elements is proposed. These structures are economically efficient because all the elements of the truss, subjected to the force action complicated by torsion, operate under conditions of more simple force effect. Experimental studies confirmed the correctness of evaluation of the forces in the elements of the plate-stem structure design and calculations of its strength and deformability.
    Key words: plate-stem truss, static analysis of trusses, reinforced concrete structures, truss torsion angle, bending and torque moments.
  • REFERENCES
    1. Chanakya Arya. Design of Structural Elements. Concrete, steelwork, masonry and timber designs to British Standards and Eurocodes. USA, Taylor&Francis e-Library, 2009. 502 p.
    2. Almazov V. O., Topilin A. N. Rukovodstvo dlya proektirovshchikov k Evrokodu 4: proektirovanie stalezhelezobetonnykh konstruktsiy EN 1994-1-1 [Eurocode 4. Guidebook for engineers: design of reinforced concrete structures]. Moscow, MGSU Publ., 2012. 412 p. (In Russian).
    3. Topilin A. N. Plate-stem reinforced concrete structures with high torsion resistance. Vestnik MGSU, 2011, no. 2-1, pp. 105-109. (In Russian).
    4. Tamrazyan A. G., Orlova M. A. Experimental research of strain-stress distribution of cracked bended elements made of reinforced concrete. Vestnik TGASU, 2015, no. 6, pp. 98-105. (In Russian).
    5. Tamrazyan A. G., Mkrtychev O. V., Dorozhinskiy V. B. Design of long span structure with danger exposures using nonlinear dynamics methods. Nauchno-tekhnicheskiy vestnik Povolzh'ya, 2012, no. 5, pp. 331-334. (In Russian).
    6. Klyueva N. V., Tamrazyan A. G. Main properties of structure systems, which are decreasing failure risk in elements of the building. Izvestiya Yugo-Zapadnogo gosudarstvennogo universiteta, 2012, no. 5-2 (44), pp. 126-131. (In Russian).
    7. Ivanchev I. I., Topurov K. H., Topilin A. N., Ivanenko N. I. Zhelezobetonnye avtodorozhnye mosty [Reinforced concrete road bridges]. Moscow, ASV Publ., 2008. 280 p. (In Russian).
    8. Alekseev Yu. V., Topilin A. N., Komarova I. M. The influence of external forces from additional structures and zigzag traced mansard roofs to 1950-60 years-built domestic houses. Promyshlennoe i grazhdanskoe stroitel'stvo, 2001, no. 3, pp. 39-40. (In Russian).
  • To Accounting Profiled Sheeting Аs Working Reinforcement In The Calculation Of Monolithic Steel-Concrete Floor Slabs
  • UDC 624.016.5:624.12.35:624.07.73
    Ashot G. TAMRAZYAN, e-mail: tamrazian@mail.ru
    Sevak N. HARUTYUNYAN, e-mail: sevak.harutyunyan@mail.ru
    National Research Moscow State University of Civil Engineering, Yaroslavskoe shosse, 26, Moscow 129337, Russian Federation
    Abstract. An analysis of the work of monolithic composite slabs of overlaps from profiled decking as working reinforcement has been made. It is shown that even under the action of vertical loads several stages of work that are very different from each other appear. Due to the maturity of the theory of conventional reinforced concrete, the calculated model of such structures is to be built as for a reinforced concrete slab in which steel profiled decking is used as external working reinforcement providing the joint work of profiled decking with concrete. Different calculation methods for determining the bearing capacity of such structures by shear according to Russian recommendations and recommendation of the Eurocode 4 are presented. For calculation according to the Eurocode 4, it is necessary to have experimental data of nature samples, and the calculations according to the Russian methodology provide the anchorage of profiled decking with concrete with due regard for the coefficient of conditions of profiled decking operation, which is adopted depending on the type of forge on walls and the availability of anchor supports. It is concluded that when calculating the monolithic steel-reinforced concrete overlap slabs with profiled decking as working reinforcement, it is necessary to take into account parameters influencing on the joint operation of profiled decking and concrete, forms of profile decking corrugations, thickness of the profiled decking and the slab.
    Key words: steel composite slab, profiled decking, joint work of profiled decking with concrete, shearing strength, coefficient of profiled decking work.
  • REFERENCES
    1. Eurocode 4: Design of steel and concrete structures. CEN. Brussel, 2004. 118 p.
    2. STO 0047-2005. Perekrytiya stalezhelezobetonnye s monolitnoy plitoy po stalnomu profilirovannomu nastilu. Raschyot i proektirovanie [Overlap with monolithic steel-concrete composite slab on steel decking. Calculation and design]. Moscow, TsNIIPSK im. Mel'nikova Publ., 2005. 65 p. (In Russian).
    3. Ayrumyan E. L., Kameneshikov N. I., Rumyanceva I. A. Features of design of monolithic slabs for steel concrete ceiling on profiled steel decking. Promyshlennoe I grazhdanskoe stroitelstvo, 2015, no. 9, pp. 21-26. (In Russian).
    4. Rumyanceva I. A. Determination of specific-conditions-of-use factors for the steel profiled decking jointly with reinforced concrete floor constructions for calculation of strenght along normal sections at the stage of operation. Stroitelnaya mekhanika inzhenernykh konstrukciy i sooruzheniy, 2009, no. 1, pp. 24-28. (In Russian).
    5. Namdeo А. H., Namdeo R., Laxmikant М. G. Composite concrete slabs with profiled steel decking: comparison between. Experimental and simulation study. American Journal of Civil Engineering, 2015, vol. 3, no. 5, pp. 157-169.
    6. Porter M. L., Ekberg C. E., Greimann L. F., Elleby H. A. Shear bond analysis of steel deck reinforced slabs. ASCE Journal of the Structural Division, 1976, vol. 102, no. 12, pp. 2255-2268.
    7. Tamrazyan A. G., Harutyunyan S. N. To the assessment of reliability of composite steel reinforced concrete floor slabs with a profiled decking. Vestnik grazhdanskikh inzhenerov, 2015, no. 6(53), pp. 52-57. (In Russian).
    8. Almazov V. O., Harutyunyan S. N. Design of composite reinforced concrete slabs according to Eurocode 4 and russian recommendations. Vestnik MGSU, 2015, no. 8, pp. 51-65. (In Russian).
  • Causes and Mechanisms of Maintenance Damage of Reinforced Concrete Balcony Slabs of Residential Buildings
  • UDC 69.022.385:699.8
    Anna N. MALAKHOVA, e-mail: GBK@mgsu.ru
    National Research Moscow State University of Civil Engineering, Yaroslavskoe shosse, 26, Moscow 129337, Russian Federation
    Abstract. Balconies belong to the bearing elements of a building, but in contrast to the floor slabs protected against atmospheric impacts, balcony slabs are under difficult operating conditions. The article discusses the power loads and climatic impacts on balcony slabs of residential buildings. A constructive solution, reinforcement and fracture character of balcony slabs under load are shown. The causes and mechanisms of the concrete and reinforcement destruction due to the atmospheric precipitation, temperature drop of outdoor air, heating of structures because of the intensive solar radiation etc are described. Results of the survey of the technical state of balcony slabs of the apartment building, which operates over 40 years, are presented. Recommendations for maintenance of open balconies are made; examples of modern apartment buildings with glazed balconies are presented. The use of up-to-date efficient finishing and waterproofing materials makes it possible to ensure the proper durability of residential building balconies.
    Key words: maintenance damages, reinforced concrete balcony slabs, constructive solution, reinforcement, fracture character, climatic impacts.
  • REFERENCES
    1. Popov G. T., Burak L. A. Tehnicheskaja jekspertiza zhilyh zdanij staroj zastrojki [The technical expertise of old residential buildings]. Leningrad, Stroyizdat Publ., 1986. 240 p. (In Russian).
    2. Mikhalko V. R. Remont konstrukcij krupnopanel'nyh zdanij [The Renovation of building constructions of large panels buildings]. Moscow, Stroyizdat Publ., 1986. 312 p. (In Russian).
    3. Kolotilkin B. M. Dolgovechnost' zhilyh zdanij [The durability of residential buildings]. Moscow, Stroyizdat Publ., 1965. 249 p. (In Russian).
    4. Grassnik A., Grun E., Fiks B., et al. Preduprezhdenie defektov v stroitel'stve: zashhita materialov i konstrukcij [Preventing of defects in the construction: protection materials and Structures]. Moscow, Stroyizdat Publ., 1989. 216 p. (In Russian).
    5. Bedov A.I., Znamensky V. V., Gabitov A. I. Ocenka tehnicheskogo sostojanija, vosstanovlenie i usilenie osnovanij i stroitel'nyh konstrukcij jekspluatiruemyh zdanij i sooruzhenij [Evaluation of technical condition, restoration and strengthening of foundations and building structures of exploited buildings]. Part 1. Moscow, ASV Publ., 2014. 704 p. (In Russian).
    6. Malakhova A. N., Malakhov D. Y. Ocenka nesushhej sposobnosti stroitel'nyh konstrukcij pri obsledovanii tehnicheskogo sostojanija zdanij [The evaluation of the bearing capacity of building structures during the survey of technical condition of buildings: a training manual]. Moscow, MGSU Publ., 2015. 96 p. (In Russian).
    7. Shereshevskii I. A. Konstruirovanie grazhdanskih zdanij [Designing of civil buildings]. Moscow Arkhitektura-S Publ., 2005. 176 p. (In Russian).
    8. Tamrazyan A. G. To the tasks of monitoring of the risk of buildings. Stroitel'nye materialy, oborudovanie, tekhnologii XXI veka, 2013, no. 3 (170), pp. 19-21. (In Russian).
    9. Dudin I. V., Tamrazyan A. G. Providing the quality of precast reinforced concrete structures at the manufacturing stage. Zhilishchnoe stroitel'stvo, 2001, no. 3, pp. 8-10. (In Russian).
  • Calculation for the Formation of Normal Cracks on the Basis of Deformation Model
  • UDC 666.972:691.620.192
    Nikolai N. TREKIN, e-mail: otks@narod.ru
    National Research Moscow State University of Civil Engineering, Yaroslavskoe shosse, 26, Moscow 129337, Russian Federation
    Emil N. KODYSH, e-mail: otks@narod.ru, Dmitriy N. TREKIN
    TSNIIPromzdanii, Dmitrovskoe shosse, 46, korp. 2, Moscow 127238, Russian Federation
    Abstract. Concrete as a composite material has many initial cracks arising during hardening. But the effort (the moment or longitudinal force) is accepted as an estimate indicator of cracking formation when micro-cracks unite in macro- cracks and become visible. Basic provisions for definition of the moment of normal cracks formation in the flexural elements on the basis of the deformation theory recommended by the СП 63.13330.2012 are presented. On the basis of the bilinear settlement chart of concrete deformation at compression and stretching, expressions for definition of the moment of cracks formation with due regard for the ordinary and pre-stressed reinforcement have been obtained. According to these dependences numerical studies have been conducted and results have been compared with known experimental data. It is revealed that the received dependences on the basis of recommendations of the СП 63.13330.2012 give underestimated indicators of the moment of crack formation. Proposal for adjusting the parameters of the bilinear settlement chart of conditions of concrete for better convergence with experimental data have been developed.
    Key words: stress-strain state, crack resistance, deformation model, deformation chart of concrete, width of crack growth.
  • REFERENCES
    1. Zalesov A. S., Kodysh E. N., Lemysh L. L., Nikitin I. K. Raschet zhelezobetonnyh konstruktsiy iz tyazhelogo betona po prochnosti, treshchinostoykosti i deformatsiyam [The calculation of reinforced concrete structures for strength, fracture toughness and deformation]. Moscow, Stroyizdat Publ., 1988. 320 p. (In Russian).
    2. Polozhnov V. I., Trifonov V. I., Polognov A. V. Evaluation of cracking in pre-stressed decks, reinforced with mild steel. Beton I zhelezobeton, 2006, no. 2, pp. 14-17. (In Russian).
    3. Murashev V. I. Treshchinoustoychivost', zhestkost' I prochnost' zhelezobetona [Tremendoustomato, the stiffness and strength of reinforced concrete]. Moscow, Mashstroyizdat Publ., 1950. 268 p. (In Russian).
    4. Bondarenko V. M., Ivanov A. M., Baydin O. V., Tsareva A. D. Some questions of the theory of reinforced concrete. Stroitel'stvo i rekonstruktsiya, 2012, no. 4, pp. 25-29. (In Russian).
    5. Karpenko N. I., Sokolov B. S., Radaykin O. V. Analysis and enhancement of curvilinear diagrams of concrete deformations for calculation of reinforced concrete structures on the basis of a deformation model. Promyshlennoe I grazhdanskoe stroitelstvo, 2013, no. 1, pp. 28-30. (In Russian).
    6. Kodysh E. N., Trekin N. N., Trekin D. N. Influence of parameters of the idealized concrete deformation diagrams on the calculated values of strength, fracture toughness and bending deformations and eccentrically compressed elements. "Beton i zhelezobeton - vzglyad v budushchee". Nauch. tr. III Vserossiyskoy (II Mezhdunarodnoy) konferentsii po betonu i zhelezobetonu. ["Concrete and reinforced concrete - cleance at future". Scientific works of the III All Russian (II International) conference on concrete and reinforced concrete: in 7 vol.]. Moscow, MGSU Publ., 2014. Vol. I. Pp. 69-75. (In Russian).
  • BUILDING MATERIALS AND PRODUCTS
  • The Use of Polymer Composite Rebar for Supports of the Contact-Line with Anchorage on Foundations
  • UDC 691.87:693.554:691.175
    Valeriy N. NIKOLAEV
    OOO «Galen», ul. K. Marksa, 52, Chuvashskaya Respublika, Cheboksary 428008, Russian Federation
    Valentina F. STEPANOVA, e-mail: vfstepanova@mail.ru
    NIIZHB named after A. A. Gvozdev Research Center of Construction, 2-ya Institutskaya ul., 6, Moscow 109428, Russian Federation
    Abstract. The technology for pre-stressing and anchoring of composite rebar which makes it possible to reinforce concrete products and produce the contact-line supports of high quality, which possess advantages in comparison with the reinforced concrete, has been developed. The prototypes of the posts of supports with the use of composite basalt-plastic reinforcement, which were tested for strength, rigidity and crack resistance in NIIZHB named after A. A. Gvozdev, have been prepared. In the course of testing, the value of deflection of the post in the plane of application of the control load was determined. Posts with composite reinforcement (with vibro-loading and after vibro-loading) and metallic posts were tested. Results of the study show that the vibro-loading had no significant impact on the properties of supports, reinforced with composite rebar. The results obtained confirm the possibility to use concrete posts of contact-line supports, reinforced with pre-stressed composite rebar. In the future, it is necessary to develop the working drawings for the replacement of steel reinforcement by composite polymer rebar and the technical conditions for supports of the contact-lines of Russian Railways as well as the technical regulations for their manufacturing.
    Key words: composite rebar, supports of contact-line, railways, pre-stressed reinforced concrete, multiple re-loading.
  • REFERENCES
    1. Lapshinov A. E. Prospects of application of non-metallic composite reinforcement as a non-stressed working in compressed elements. Vestnik MGSU, 2015, no. 10, pp. 96-106. (In Russian).
    2. Aftab A. M., Kennelt W. N. State of the art of FRP and SHM application in bridge structures in Canada. Composite Research Journal, vol. 2, iss. 2, spr. 2008, рp. 60-69.
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    4. Stepanova V. F., Stepanov A. Yu. Non-metallic composite reinforcement for concrete structures. Promyshlennoe i grazhdanskoe stroitel'stvo, 2013, no. 1, pp. 45-47. (In Russian).
    5. Stepanova V. F. The production and application of composite materials, products and structures in construction industry. Stroitel'nye materialy, oborudovanie, tekhnologii XXI veka, 2014, no. 2, pp. 27-29. (In Russian).
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    7. Patent 2388878 RU. Armatura kompozitnaya [Fittings composite]. A. S. Shakhov, S. V. Shakhov, S. I. Shabalin, E. V. Lyalin, V. F. Stepanova. Available at: http://www.freepatent.ru/patents/2388878 (accessed 22.06.2006). (In Russian).
    8. Patent 2203372 RU. Ustanovka dlya vypolneniya ankernykh zatsepov na armaturnykh sterzhnyakh [An installation for performing the anchor hooks on reinforcing bars]. V. N. Nikolaev. Available at: http://www.findpatent.ru/patent/220/2203372.html (accessed 10.11.2011). (In Russian).
  • The Use Of Penoplex® Boards As An Effective Filler For The Systems Of Deformation Joints Of Designs Of Buildings And Structures