- Durability and Deformability of Precast-Cast-in-Place Frameworks for Residential Buildings with Low Material Consumption at Beyond-Design-Basis Impacts
- UDC 624.016.5:728
Natalia V. KLUEVA, ň-mail: email@example.com
Vitaly I. KOLCHUNOV, e-mail: firstname.lastname@example.org
Dmitry A. RYPAKOV, e-mail: email@example.com
Anastasiya S. BUKHTIYAROVA, e-mail: firstname.lastname@example.org
Southwest State University, ul. 50 let Oktyabrya, 94, 305040 Kursk, Russian Federation
Abstract. Despite the diversity of the applied architectural-building systems, industrially constructed residential buildings of economy class are most widely used to solve the housing problem of the majority of Russians. In this context, the enhancement and development of new types of industrial systems of buildings are actual from the point of view of reducing the material consumption, increasing durability, improving environmental friendliness, energy efficiency and thermal performance. The paper presents a new constructive solution of precast-cast-in-place framework for residential buildings with low material consumption as well as results of its numerical studies under design loads and beyond-design-basis impacts. Features of the stress-strain state of structural elements of the precast-cast-in-place framework made of industrially manufactured lightweight panel-frames and proposals concerning the adaptation mechanisms of protection of the considered type of structures against progressive collapse in the event of unexpected beyond-design-basis impacts are analyzed. As the studies show the lightweight precast-cast-in-place framework of the multistory building made of panels-frames meets the requirements of limit states and can be used in housing construction. The spatial stability of the frame is ensured by the connection of panel posts and monolithic sections of girders with protruding bars, arrangement of the continuity of precast-cast-in-place girders of panel-frames and the mutually orthogonal location of disks of floor slabs. In some cases for protection against progressive collapse it is reasonable to split the framework into separate fragments pivotally connected with each other.
Key words: residential buildings, precast-cast-in-place framework, beyond-design- basis impact, progressive collapse.
1. Nikolev S. V. Panel and frame buildings of new generation. Zhilishchnoe stroitelstvo, 2013, no. 8. pp. 2-9. (In Russian).
2. Klueva N. V., Kolchunov V. I., Bukhtiyarova └. S. Resource-energy saving structural system for residential and public buildings with a preset level of structural safety. Promyshlennoe i grazhdanskoe stroitelstvo, 2014, no.2, pp. 37-41. (In Russian).
3. Ilyichev V. A., Kolchunov V. I., Kobeleva S. A. A criterion model of full resource cycle is a basis of ecological safety of construction. Promyshlennoe i grazhdanskoe stroitelstvo, 2014, no.12, pp. 3-6. (In Russian).
4. Bondarenko V. M., Kolchunov V. I. Raschetnye modeli silovogo soprotivleniya zhelezobetona [Settlement models of power resistance of reinforced concrete]. Moscow, ASV Publ., 2004. 472 p. (In Russian).
5. CTO-008-02495342-2009. Prevention of the progressing collapse of ferroconcrete monolithic designs. Moscow, 2009. 23 p. (In Russian).
6. Almazov V. O., Kjoy Cao Zuy. Dinamika progressiruyushchego razrusheniya monolitnykh mnogoetazhnykh karkasov [Dynamics of the progressing destruction of monolithic multystoried frameworks]. Moscow, ASV Publ., 2013. 128 p. (In Russian).
- Study Of Safe Operation Of Solid Reinforced Concrete Foundation Plates Under The Column Grid Using Reinforced Concrete Models
- UDC 624.153.5.012.45
Sergei I. POLITOV, e-mail: email@example.com
North-Caucasus Federal University (NCFU), branch of NCFU in Pyatigorsk, ul. 40 let Octyabrya, 56, Pyatigorsk 357500, Russian Federation
Sergey Ju. KALASHNIKOV, e-mail: firstname.lastname@example.org
Valeria A. PSHENICHKINA, e-mail: email@example.com
Volgograd State University of Architecture and Civil Engineering, ul. Academicheskaya, 1, Volgograd 400074, Russian Federation
Victor G. SHARAPOV, e-mail: firstname.lastname@example.org
INZHGEOPROEKT, Kuchury ul., 8, Pyatigorsk 357500, Russian Federation
Abstract. Actual issues of improving the safe operation of solid concrete foundation plates under the column grid are considered in the course of comprehensive research with the use of models. It is shown that during the study of the stress-strain state of the "base-foundation-aboveground structure" system it is necessary to observe the similarity of the system in terms of flexibility, which is maintained in compliance with the ratio of the deformation modulus of subsoil and a foundation slab both for a full-scale structure and for a model. The revealed regularity made it possible to develop a special stand for conducting the study in the course of the elastic stage of the system operation. After testing the system operation, the program was specified and research works with the use of reinforced concrete models of foundation slabs under regular and irregular column grids with the study of the picture of redistribution of stresses both in the foundation slab and in columns with measurement and construction of diagrams of contact normal and shear stresses, schemes of cracking formation and fracture patterns of models of base plates under the column grid were conducted. On the basis of results of the experimental study of solid foundation slabs in the full range of loads until the foundation failure, the kinematic method of limit equilibrium is used for calculation of similar designs. Previously, Prof. S. M. Krylov applied this method for calculation of beamless monolithic concrete floors. Unlike floors, reinforced concrete foundations operation is more complex due to the redistribution of contact normal stresses, emergence and further transformation of contact tangential stresses which provide unloading effect on the operation of the structure. The method can be used as a check calculation for designing solid reinforced concrete foundation slabs under the column grid, this will greatly improve the safety of the system "base- foundation-aboveground structure" operation.
Key words: safety, solid foundation slab, stress-strain state, column grid, fracture scheme, kinematic method of limit equilibrium.
1. Skibin G. M., Shmatkov V. V., Borlikov G. M. Experimental and theoretical study of linear and nonlinear methods of calculation bases and foundations with the use of information technology. Aktual'nye problemy fundamentostroeniya na Yuge Rossi. Materialy nauchno-prakt. konf., posvyashchennoy pamyati professorov Yu. N. Murzenko i A. P. Pshenichkina (14-15 iyulya 2010 g., YuRGTU - NPI) [Actual problems of foundation in the south of Russia. Materials of scientific-practical use. conf., dedicated to the memory of professors Y. N. Murzenko and A. P. Pshenichkina]. Novocherkassk, YuRGTU Publ., 2010, pp. 5-13. (In Russian).
2. Ulitskiy V. M., Shashkin A. G. Field studies as the basis for developing a methodology for the calculation of stress-strain state of an ground at the device of underground structures. Osnovaniya, fundamenty i mekhanika gruntov, 2011, no. 4, pp. 2-8. (In Russian).
3. Obozov V. I., Tolstykh M. A. Analysis of stress-strain state of a base plate on collapsible soils under seismic loads. Osnovaniya, fundamenty i mekhanika gruntov, 2011, no. 1, pp. 20-23. (In Russian).
4. Sapozhnikov A. I., Egupov K. A. Work of the precast slab in its plane and ways to increase its strength and stiffness. Promyshlennoe i grazhdanskoe stroitel'stvo, 2014, no. 5, pp. 54-58. (In Russian).
5. Politov S. I. Features of calculation of solid concrete slabs on the kinematic method of limit equilibrium. Akademicheskie chteniya "Aktual'nye problemy betona i zhelezobetona. Materialy i konstruktsii, raschet i proektirovanie", Kislovodsk, 2010, pp. 140-143. (In Russian).
- Heat Treatment Of Concrete Mix In Cast-In-Situ Structures
- UDC 693.547.3
Alexander P. SVINTSOV, e-mail: email@example.com
Yury V. NIKOLENKO, e-mail: firstname.lastname@example.org
Vladimir V. KURILKIN, e-mail: email@example.com
Peoples' Friendship University of Russia, Miklukho-Maklaya ul., 6, Moscow 117198, Russian Federation
Abstract. Cast-in-situ construction in the cold season is associated with the need to prevent the freezing of chemically unrelated mixing water in the initial period of structural formation of concrete. This is especially important for the climatic conditions of Russia, where the cold season lasts 6-7 months. One of the methods of concreting in winter is the heat treatment of casted structure during its hardening and the acquiring of a critical or design strength before the freezing. Heat treatment using the infrared heating for a diurnal cycle makes it possible to obtain approximately 70% of the design strength of concrete. However, intensive evaporation from the surface of un-shuttered concrete mix leads to the shrinkage stresses in the concrete and reduce its quality parameters. The option of improving the technology of cast-in-situ concrete and reinforced concrete structures erection in the cold season for concrete heating using the infrared radiation is presented. On the un-shuttered surface of laid concrete, we installed without gaps the elements of covering made of several layers of transparent material, for infrared ray, fixed with pulling on the frame. A closed air space between the transparent layers serves as a thermal insulator, and a closed air space on the concrete surface restrains the evaporation to the atmosphere. For the practical purposes of concrete heating, in the conditions of construction, as a transparent material for infrared ray, it is appropriate to use the polyethylene-terephthalate film. The developed technology of heat treatment of the laid and compacted concrete mix with the use of infrared heating and dual-chamber transparent covering for infrared rays ensures the conditions for normal chemical reaction of hardening and strengthening. This allows us to successfully meet challenges of winter concreting in the course of construction of buildings and structures of cast-in-situ concrete and reinforced concrete.
Key words: concrete, strength, temperature, heating, infrared radiation.
1. Khrenkov N. N., Shishkin V. V. To the choice of a method of electrothermy at winter concreting. Promyshlennoe i grazhdanskoe stroitel'stvo, 2010, no. 6, pp. 58-60. (In Russian).
2. Svintsov A. P., Nikolenko Yu. V., Patrakhal'tsev N. N., Ivanov V. N. Improvement of technology of concrete works in monolithic housing construction. Stroitel'nye materialy, 2012, no. 1, pp. 28-32. (In Russian).
3. Patent RF 2135713. Afanas'ev A. A. Termoaktivnyy opalubochnyy shchit [Thermoactive shuttering board]. 1999. (In Russian).
4. Patent RF ╣ 2178492. Abdullin I. B., Kazakov M. E., Kazimirov I. A., Blagodarov Yu. A., Afanas'ev A. A. Termoaktivnaya opalubka [Thermoactive timbering]. 2002. (In Russian).
5. Svintsov A. P., Nikolenko Yu. V., D'yakonov V. V. Technology of capital repairs of engineering silage constructions. Vestnik RUDN. Inzhenernye issledovaniya, 2012, no. 1, pp. 19-24. (In Russian).
6. Patent RF ╣ 113287. Svintsov A. P., Svintsova N. K., Nikolenko Yu. V., Gladchenko L. K. Ustroystvo dlya teplovoy obrabotki betonnoy smesi v monolitnykh konstruktsiyakh [The device for thermal treatment of concrete mix in monolithic designs]. 2012. Byul. ╣ 4. (In Russian).
7. Plaksin Yu. M., Filatov V. V., Doronin A. F., Goncharov M. V., Kulikova M. G. Osnovy teorii infrakrasnogo nagreva [Bases of the theory of infrared heating]. Moscow, MGUPP Publ., 2007. 168 p. (In Russian).
8. Rukovodstvo po progrevu betona v monolitnykh konstruktsiyakh [The guide to warming up of concrete in monolithic designs]. Pod red. B. A. Krylova, S. A. Ambartsumyana, A. I. Zvezdova. Moscow, Krasnyy proletariy Publ., 2005. 275 p. (In Russian).
9. Podgornov N. I. Termoobrabotka betona s ispol'zovaniem solnechnoy energii [Heat treatment of concrete with use of solar energy]. Moscow, ASV Publ., 2010. 328 p. (In Russian).
- Ways Of Improving The Competitiveness Of Foam Concrete In Present Conditions And Prospects Of Its Application In Construction
- UDC 691.327.33:666.973
Nabi T. DAUZHANOV1, e-mail: Dauzhanov@mail.ru
Boris A. KRYLOV2, e-mail: Krylov-BA@mail.ru
Liazat B. ARUOVA1, e-mail: firstname.lastname@example.org
1 Korkyt Ata Kyzylorda State University, Aiteke bie str., 29A, City of Kyzylorda 120014, Republic of Kazakhstan
2 NIIZhB named after A. A. Gvozdev, 2 Institutskaya ul., 6, Moscow 109428, Russian Federation
Abstract. The issues being discussed are the ways of improving the competitiveness of foam concrete in modern conditions by creating the simple energy-saving technology which eliminates the most energy-intensive redistributions (autoclaving, steam heating), and their replacement with energy-saving ways of intensification of hardening - solar heating. This makes it possible to ensure high physical and mechanical properties of foam concrete and the expansion of areas of its application. The results of experiments on solar heat treatment of products from foam concrete under conditions of dry and hot climate of Kazakhstan are presented. For intensification of the hardening of foam concrete products by solar heating in order to ensure its uniformity and reduce temperature gradients in the hardening concrete, the use, along with solar energy, of additional electrical energy, the impact of which on the hardening concrete can be periodic and of short duration, is justified. The kinetics of heating and gain in strength of foam concrete products with different thickness has been studied. The obtained data indicate that the favorable humidity environment for hardening and mild temperature conditions of the solar heat treatment promote the formation of the optimal structure and improved physical and mechanical properties of the foam concrete. The information about the micro-composition of some elements of the structure has been received with the help of methods of scanning electronic microscopy.
Key words: foam concrete, hardening intensification, helioheating, soft modes, energy-saving technology, hot dry climate, exothermicity of cement.
1. Sakharov G. P., Strel'bitskiy V. P. Development prospects of production and improve the quality of cellular concrete on the basis of traditional and alternative. Beton i zhelezobeton, 2010, no. 1 (562), pp. 5-9. (In Russian).
2. Sokov V. N., Zhabin D. V., Zemlyanushnov D. Yu. On the issue of foam concrete creation in hydro-heat-force field. Promyshlennoe i grazhdanskoe stroitel'stvo, 2013, no. 3, pp.12-14. (In Russian).
3. Dauzhanov N. T., Aruova L. B. Using solar energy to heat treatment of concrete in Kazakhstan. ALITinform, 2010, no. 3 (20), pp. 14-18. (In Russian).
4. Zasedatelev I. B., Malinski E. N., Temkin E. S. Geliotermoobrabotka sbornogo zhelezobetona [Solar heat treatment of reinforced concrete]. Moscow, Stroyizdat Publ., 1990. 312 p. (In Russian).
5. Shchukina T. V., Akopyan A. V., Semenova E. U. Solar energy resources CCA for use in the manufacture of building products. Tekhnologiya betonov, 2014, no. 9, pp. 45-47. (In Russian).
6. Podgornov N. I. Termoobrabotka betona s ispol'zovaniem solnechnoj jenergii [Heat treatment of concrete by solar energy]. ╠oscow, └Đ┬ Publ., 2010. 328 p. (In Russian).
7. Krylov B. A., Ambarcumjan S. A., Zvezdov A. I. Rukovodstvo po progrevu betona v monolitnyh konstrukcijah [Manual for heating concrete in monolithic structures]. ╠oscow, Krasniy proletariy Publ., 2005. 276 p. (In Russian).
8. Pivovarova Z. I., Stadnik V. V. Klimaticheskie kharakteristiki solnechnoi radiatsi kak istochnika energii na territorii SSSR [Climatic characteristics of solar radiation as an energy source in the USSR]. ╠oscow, Gidrometeoizdat Publ., 1988. 18 p. (In Russian).
9. Zhumagulov B. T. A New Kazakhstan will be built according to world standards of quality. Promyshlennoe i grazhdanskoe stroitel'stvo, 2013, no. 7, pp. 96-98. (In Russian).
10. Malinina L. A. Teplovlazhnostnaja obrabotka tjazhelogo betona [Heat and humidity treatment of heavy concrete]. Moscow, Stroyizdat Publ., 1977. 160 p. (In Russian).
- Study of Work of Decorative Plates under Operation Conditions
- UDC 691:693.69:699.86
Viktor P. YARTSEV, e-mail: email@example.com
Aleksandňr V. EROFEEV, e-mail: AV.Erofeev@yandex.ru
Tambov State Technical University, ul. Sovetskaya, 106, Tambov 392000, Russian Federation
Abstract. The influence of weather on the operational properties of the decorative plates, intended for finishing the facades of buildings is investigated. Atmospheric effects were simulated by climatic tests: freezing - thawing cycles, thermal aging and ultra-violet radiation. Durability at cross-bending, hardness of the decorative layer, thermal expansion, water absorption, and swelling processes are considered as the main operational properties. The choice of these properties is caused by the specificity of decorative plates work. The article presents experimental dependences of the change in operational characteristics of decorative plates on the duration of atmospheric factors impact and considers the causes of such changes. The technique of definition of operational durability of decorative plates is given. The influence of aggressive liquid media on the strength characteristics of plates is also considered. It is experimentally established that in the course of the cyclic freezing-thawing, the operational characteristics of decorative plates are reduced due to the destruction of the material's base when the liquid transfers from one aggregate state to another one.
Key words: decorative plates, hardness of decorative layer, atmospheric factors, heat expansion, water absorption and swelling, aggressive liquid media.
1. Ponomarev O. I., Verenkova E. M., Stepanova V. F. [et al.]. Protective and decorative coverings of bearing designs and facades of buildings. Promyshlennoe i grazhdanskoe stroitel'stvo, 2007, no. 3, pp. 37-39. (In Russian).
2. Starodubtsev V. G., Povetkin S. V. Ensuring operational properties of protecting designs. Promyshlennoe i grazhdanskoe stroitel'stvo, 2009, no. 5, pp. 45-46. (In Russian).
3. Erofeev A.V. Influence of atmospheric actions on the hardness of decorative plates. Vestnik Cherepovetskogo gosudarstvennogo universiteta, 2013, vol. 2, no. 1(46), pp. 14-17. (In Russian).
4. Kiseleva O. A., Yartsev V. P. Influence of structure and structure on durability, durability and water resistance of wood materials in construction products and designs. Vestnik Voronezhskogo gosudarstvennogo arhitekturno-stroitelnogo universiteta. Ser. Stroitelstvo i arhitektura, 2008, no. 4, pp. 91-100. (In Russian).
5. Erofeev A. V. Influence of atmospheric actions on processes of water absorption and swelling of decorative plates. Vestnik grazhdanskih inzhenerov, 2013, no. 3 (38), pp. 113- 116. (In Russian).
6. Yartsev V. P., Erofeev A. V. Influence of hostile environment on durability of decorative plates. Voprosyi sovremennoy nauki i praktiki, 2012, no. 2(40), pp. 14-17. (In Russian).
- The Use of Saponite-Containing Material for Producing Frost-Resistant Concretes
- UDC 691.535:666.972.53
Marina V. MOROZOVA, e-mail: firstname.lastname@example.org
Arkady M. AYZENSTADT, e-mail: email@example.com
Tatiana A. MAKHOVA, e-mail: firstname.lastname@example.org
Northern (Arctic) Federal University, Severnaya Dvina Emb. 17, Arkhangelsk 163002, Russian Federation
Abstract. A method for controlling the water-cement ratio of the concrete mix in the process of its hardening by the introduction of finely-dispersed additives of saponite-containing material (SCM), extracted from tailings of kimberlite ores of the diamond mining industry of the Arkhangelsk Region (deposit named after M. V. Lomonosov) is proposed. It is shown that the most efficient additive has an average particle size in the range of 400-600 nm. The dependence between the water absorption and the degree of dispersion of the material, which makes it possible to calculate the necessary amount of the additive in the composite mixture, has been obtained. Tests of prototypes of fine concrete with SCM for compressive strength were conducted; the brand of frost resistance of the concrete composite has been determined. Results of the test of prototypes for compressive strength show that the optimal amount of the SCM additive is 7% of the mix. This makes it possible more than to double the strength of concrete, improve the brand of frost resistance of the concrete composite up to F150.
Key words: saponite, concrete, strength, frost resistance, specific surface, water absorption, water-cement ratio, particle size, finely-dispersed material.
1. Dobshits L. M. Osnovy polucheniya dolgovechnykh betonov [Fundamentals of concrete durability]. Stroitel'noe materialovedenie. Teoriya i praktika. sb. tr. Vseros. nauch.-prakt. konf. Moscow, SIP RIA Publ., 2006. Pp. 39-45. (In Russian).
2. Bazhenov Yu. M. Tekhnologiya betona [Concrete technology]. Moscow, ASV Publ., 2002. 500 p. (In Russian).
3. Morozova M. V., Ayzenstadt A. M., Tutygin A. S. Water absorption of saponite-containing tails of kimberlite ore dressing. Promyshlennoe i grazhdanskoe stroitel'stvo, 2013, no. 11, pp. 29-31. (In Russian).
4. Smirnov V. A., Korolev E. V., Al'bakasov A. I. Size effects and topological features of nano-modified composites. Nanotekhnologii v stroitel'stve, 2011, no. 4 (14), pp. 17-26. (In Russian).
5. Tutygin A. S. Nanodispersnye modifikatory iz otkhodov obogashcheniya almazodobyvayushchey promyshlennosti [Nanodispersed modifiers of the tailings of the diamond industry]: dis. ... kand. tekhn. nauk. Belgorod : BGTU im. V. G. Shukhova, 2013. 160 p. (In Russian).
6. Tutygin A. S., Ayzenshtadt M. A., Ayzenshtadt A. M., Makhova T. A. Influence of the nature of the electrolyte on the coagulation process saponite-containing suspension. Geoekologiya, 2012, no 5, pp. 379-383. (In Russian).
7. Tutygin A., Shinraruk A., Frolova M., Aisenstadt A. Improvement of water recycling systems for water mining enterprises. J. of International Scientific Publications: Egology & Safety, 2012, vol. 6, part 1, pp. 45-54.
- Technological Aspects Of Operational Durability Of Mineral Fibers
- UDC 519.23:621.926.08:622.73
Boris M. RUMAYNCEV, e-mail: email@example.com
Alexey D. ZHUKOV, e-mail: firstname.lastname@example.org,
Moscow State University of Civil Engineering, Yaroslavskoe shosse, 26, Moscow 129337, Russian Federation
Ekaterina Yu. BOBROVA, e-mail: email@example.com
Development of low-rise building Center źHigher School of Economics╗, ul. Myasnitskaya, 20, Moscow 101000, Russian Federation
Tatyana V. SMIRNOVA, e-mail: firstname.lastname@example.org
ZAO źMineralnaya Vata╗, ul. Zemlyanoy val, 9, Moscow 121069, Russian Federation
Abstract. Stone or glass wool and basalt fiber thermal insulation materials are the most common. Mineral fibers are manufactured using rocks of gabbro-basalt group, carbonates, slag, various additives which positively influence on the fusibility of melts and their viscosity as well as on the formation of required construction properties and the operational durability of mineral-wool heat insulating materials. Production of high-quality mineral fibers with high strength characteristics and operational stability depends on the component composition of the charge, conditions and methods of melting and process refining of the melt into fiber. Indirectly, these parameters define the viscosity of the melt. Results of the research in the viscosity of mineral melts and the water resistance of mineral wool, depending on its chemical composition, the acidity module and oxide content in particular, are presented in the article. It is established that the water and chemical resistance of mineral fibers with the constant module of acidity depends on the content of calcium and magnesium oxides and their ratios in the charge. Results of the work make it possible to solve practical tasks for the optimization of chemical and mineralogical compositions of the charge components in the course of producing thermal insulation materials based on mineral fibers.
Key words: thermal insulation material, viscosity, thermal conductivity, mineral fiber, charge, operational durability, energy intensity.
1. Ovcharenko E. G. Trends in the development the production of thermal insulation in Russia. Uralstroyinfo. Moscow, 2002. URL: www.uralstroyinfo.ru. (accessed 31.08.13). (In Russian).
2. Gagarin V. G. Thermal protection and energy efficiency in update version of SNIP "Thermal protection of buildings". III International Congress. Energy efficiency XXI century. Sankt-Peterburgs, 2011, pp. 187-191. (In Russian).
3. Zhukov A. D., Smirnova T. V., Gudkov P. K. Dual density thermal insulation in the insulation envelope of buildings. Promyshlennoe i grazhdanskoe stroitel'stvo, 2013, no. 3, pp. 21-23. (In Russian).
4. Zhukov A. D., Naumova N.V., Mustafaev P. M., Mayorova N. A. Modeling properties of highly porous materials with combined structure. Promyshlennoe i grazhdanskoe stroitel'stvo, 2014, no. 7, pp. 48-51.
5. Zhukov A. D., Smirnova T. V., Zelenshchikov D. B., Khimich A. O. Thermal treatment of the mineral wool mat. Advanced Materials Research (Switzerland). 2014, vol. 838-841, . 196-200.
6. Zhukov A. D., Bessonov I. V., Sapelin A. N., Naumova N. V., Chkunin A. S. Composite wall materials. Italian Science Review. Iss. 2 (11). February 2014, pp. 155-157.
7. Goryaynov K. E., Bobrov Yu. L. Effect of chemical composition and fiber diameter on durability mineral wool. Stroitelnye materialy, 1974, no. 9, pp. 12-14. (In Russian).
8. Ponomarev V. B. Improvement of production technology and quality of thermal insulation and composite materials based on glass and mineral fibers. Mezhdunarodnaya nauch.-prakt. konf. "Effektivnye teplo- i zvukoizolyatsionnye materialy v sovremennom stroitel'stve i ZhKKh" [International Scientific-Practical Conference "Effective thermal and sound insulation materials in modern construction and Housing and Utilities"]. Moscow, MGSU Publ., 2006, pp. 109-118. (In Russian).
9. Hall C. A. Introduction to Special Issue on New Studies in EROI (Energy Return on Investment). Sustainability. 2011, no. 3 (10), pp. 1773-1777. URL: www.mdpi.com/2071-1050/3/10/1773. (accessed 20.01.2014).
10. Larkin B. K., Churchill W. Heat transfer by radiation through porous insulation. A. I. Ch. E.-jornal, 1959, no. 4, pp. 71-78.
11. Bessonov I. V., Starostin A. V., Os'kina V. M. About thermostability fibrous insulation. Vestnik MGSU, 2011, no. 3, pp. 134-139. (In Russian).
12. Rumyantsev B. M., Zhukov A. D. The principles of creation of new building materials. Mezhdunarodnaya nauch. konf. "Integratsiya, partnerstvo i innovatsii v stroitel'noy nauke i obrazovanii" [International scientific conference "Integration, partnership and innovation in building science and education"]. Moscow, MGSU Publ., 2011, pp. 150-154. (In Russian).
13. Zhukov A. D., Bobrova E. Yu., Naumova N. V. Operational insulation resistance. Vserossiyskaya nauch.-prakt. konf. "Povyshenie effektivnosti stroitel'nogo proizvodstva na osnove novykh materialov i innovatsionnykh tekhnologiy" [All-Russian scientific-practical conference "improving the efficiency of construction industry based on new materials and innovative technologies"]. Ryazan', 2013, pp. 11-19. (In Russian).
- Energy Efficiency of Operation of Ventilation Units and Central Air Conditioners
- UDC 697.9
Vladimir A. PAVLENKO, e-mail: email@example.com
Alexandr S. MARKEVICH, e-mail: firstname.lastname@example.org
Moscow State University of Civil Engineering, Yaroslavskoe shosse, 26, Moscow 129337, Russian Federation
Abstract. Ways of the saving of all forms of energy in the course of operation of ventilation and air conditioning systems of various buildings and structures are considered. Opportunities for reducing the energy consumption for heating and cooling of the air supplied to the premises to ensure their microclimate are analyzed. It is recommended to refine and optimize the norms of air exchange as well as the temperature of air inside these premises. It is shown that it's necessary to pay special attention to processes of energy utilization in the supply and exhaust ventilation units through the use of rotating regenerator blocks as the most efficient systems of energy utilization. Great potential for the use of heat pumps in the systems of ventilation and air conditioning is noted. Special attention is focused on the saving of electric power spent for operation of ventilator groups. Methods for assessment of electric power consumed by electric motors of ventilators are shown. On the basis of the European Standard EN 1886:2007, the basic characteristics and performance of ventilating units which influence on the efficiency of operation of the whole ventilation system are analyzed: mechanical strength and rigidity of the structure, tightness of the central air-conditioner body, "heat bridges" influencing on power losses at thermodynamic treatment of the air, heat transfer coefficient of the body, air overflows in the filtering section increasing the amount of unfiltered air.
Key words: power efficiency, system of heating, ventilation and air-conditioning, ventilation unit, central air-conditioner, air-tightness of body.
1. Kuvshinov Yu. Ya. Teoreticheskie osnovy obespecheniya mikroklimata pomeshcheniya [Theoretical framework for ensuring the indoor climate]. Moscow, ASV Publ., 2007. 104 p. (In Russian).
2. Naumov A. L., Kapko D. V., Efremov V. V., Budza A. O. Main directions to increase efficiency of ventilation and air conditioning systems. Promyshlennoe i grazhdanskoe stroitel'stvo, 2013, no. 6, pp. 56-59. (In Russian).
3. Livchak V. I. On the norms of the ventilation of public buildings and the consequences of their inflated. AVOK, 2007, no. 6, pp. 4-10. (In Russian).
4. Pavlenko V. A. The rate of electricity consumption SFP to estimate the cost of ventilation and air-conditioning. Vestnik MGSU, 2009, no. 3, pp. 150-155. (In Russian).
5. Global trends in the field of HVAC: opinions of experts. AVOK, 2014, no. 8, pp. 40-46. (In Russian).
- Formation of Weakened Zones over the Karst Cavity (experimental confirmation)
- UDC 624.131.3:556.332.46
Vadim S. KRASHENINNIKOV, e-mail: email@example.com
Moscow State University of Civil Engineering, Yaroslavskoe shosse, 26, Moscow 129337, Russian Federation
Abstract. In the overburden soil above the karst cavities, some areas, characterized by abnormally low values of soil strength in comparison with the surrounding array, so-called "weakened" zones, come into being. In the article, devoted to the actual theme of ensuring the safety of buildings and structures constructed in karst-dangerous areas, the possibility to forecast the sinkhole formation under conditions of the covered karst is considered. In this article, the author gives a description of an experiment performed by physical modeling of the "karst cavity - overburden soil" system, followed by an imitation of the collapse of the cavity roof and the formation of weakened zone over it. Detection of these zones is possible with the help of static or dynamic probing of soils. For the first time the author presents the experimental confirmation that above the karst cavities in overburden soils, the areas with abnormally low strength characteristics come into being that makes it possible to detect the dangerous areas before the beginning of the sinkhole development.
Key words: karst, overburden soil, karst cavity, weakened zone, softening of soil, stress-strain state of soil, dynamic probing, forecast of soil collapse.
1. Kutepov V. M., Kozhevnikova V. N. Ustojchivost' zakarstovannyh territorij [The stability of the karst areas]. Moscow, Nauka Publ., 1989. 151 p. (In Russian).
2. Savarenskij I. A., Mironov N. A. Rukovodstvo po inzhenerno-geologicheskim izyskanijam v rajonah razvitija karsta [Guidance on geotechnical investigations on the karst ares]. Moscow, PNIIIS Publ., 1995. 167 p. (In Russian).
3. Anikeev A. V., Kalinin Je. V., Tarakanov S. I. Determination of the stress state of a ground layer of karst cavity. Inzhenernaya geologija, 1991, no. 5, pp. 64-70. (In Russian).
4. Krasheninnikov V. S. Staticheskoe zondirovanie kak odin iz instrumentov ocenki karstovoj opasnosti [The Cone Penetration Test as a tool for assessment of karst hazard]. Sbornik trudov nauchnoj konferencii "Rol' inzhenernoj geologii i izyskanij na predproektnyh jetapah stroitel'nogo osvoenija territorij". Moscow, RAEN Publ., 2012, pp. 22-23. (In Russian).
5. Bondarik G. K. Osnovy teorii izmenchivosti inzhenerno-geologicheskih svojstv gornyh porod [Foundations of the theory of variation of geotechnical properties of rocks]. Moscow, Nedra Publ., 1971. 272 p. (In Russian).
6. Homenko V. P., Kolomenskij E. N. Influence of underground cavities on the state of the overlying soils. Promyshlennoe i grazhdanskoe stroitel'stvo, 2000, no. 8, pp. 39-41. (In Russian).
7. Homenko V. P. Zakonomernosti i prognoz suffozionnyh processov [The regularities and prediction of suffusion processes]. Moscow, GEOS Publ., 2003. 216 p. (In Russian).
- Constrained Concrete Shrinkage As A Factor Of Defect Development In Cast-In-Place Slabs Of Multistory Buildings
- UDC 692.522.2:721.25
Nikolay G. GOLOVIN, e-mail: firstname.lastname@example.org
Anatoliy I. BEDOV, e-mail: email@example.com
Aleksandr S. SILANT'EV, e-mail: firstname.lastname@example.org
Moscow State University of Civil Engineering, Yaroslavskoe shosse, 26, Moscow 129337, Russian Federation
Aleksandr A. VORONOV
GUP MO źMOSOBLSTROYTSNIL╗, Olympic prosp., vl. 29, str. 2, of. 602, Mytisci 141006, Russian Federation
Abstract. Results of the study of the nature and causes of cracks formation in beams and slabs of cast-in-place floors of multistory buildings with the wall structural system in the seismically dangerous area are presented. In surveyed buildings the vertical bearing structures are longitudinal and lateral walls as well as pylons connected by beams along the external and internal axes. The space stiffness of buildings is ensured by the joint operation of vertical bearing walls united by floor and roof slabs rigidly braced with them. After completion of the construction, cracks were found in floor slabs under the incomplete constant load and the absence of temporary load. It is established that the main cause of cracks formation in floor slabs is concrete shrinkage as well as some deviations in the technology of building erection. With the help of software complex "Abaqus" the computer simulation of the process of shrinking deformations and their influence on the crack formation and growth in floor structures was conducted. The calculation of crack resistance using the non-linearly deformed model showed the absence of forceful cracks. Identified defects in monolithic reinforced concrete slabs and beams of ceilings don't significantly influence on the bearing capacity and operational suitability and in the course of repairing works - on the durability of buildings.
Key words: wall structural system, cast-in-place reinforced structures, crack formation causes, cracking resistance, shrinking deformations.
1. Rekomendacii po uchetu polzuchesti i usadki betona pri raschete betonnyh i zhelezobetonnyh konstrukcij [Recommendations on concrete's creep and shrinkage for concrete and reinforced concrete structures calculations]. Moscow, Stroyizdat Publ., 1988. 122 p. (In Russian).
2. Tamrazyan A. G., Esayan S. G. Mehanika polzuchesti betona [Concrete creep mechanics]. Moscow, MGSU Publ., 2013. 490 p. (In Russian).
3. Mohamed Abou-Zeid. Control of Cracking in Concrete Structures. Reported by ACI Committee 224. 2008. 46 p.
4. Darwin D., Browning J. Evaluating free shrinkage of concrete for control of cracking in bridge decks. A Report on Research. The university of Kansas center for research. 2007. 266 p.
5. Halit Cenan Mertol, Sami Rizkalla, Paul Zia, Amir Mirmiran. Creep and shrinkage behavior of high-strength concrete and minimum reinforcement ratio for bridge columns. PCI Journal, summer 2010. . 2-18.
6. Galustov K. Z. Nelinejnaja teorija polzuchesti betona i raschet zhelezobetonnyh konstrukcij [Nonlinear concrete creep theory and reinforced concrete structures calculations]. Moscow, Fizmathlit Publ., 2006. 248 p. (In Russian).
7. Galustov K. Z. Development of concrete creep theory and perfecting of calculation method of reinforced concrete structures. Dis. doct. tehn. nauk. Moscow, 2008. 312 p. (In Russian).
- Peculiarities of Checking Calculation of Structural Designs Based on Four Points with Uneven Misalignment
- UDC 624.014.046
Nikolai N. DEMIDOV, e-mail: email@example.com
Moscow State University of Civil Engineering, Yaroslavskoe shosse, 26, Moscow 129337, Russian Federation
Abstract. The problem in question relates to the spatial beam structures, which, as a result of many years of operation, have received various damages, including those due to uneven misalignment. Domestic experience in construction and operation showes a number of positive qualities of structural designs. However, the buildings, which are in operation for over 10-20 years, require the survey and assessment of residual life. Vertical misalignment occurs in more than 90% of surveyed typical designs. The article analyzes the influence of the vertical misalignment of support assemblies on the stress-strain state of structural designs. The way to calculate bearing joints for vertical misalignment with the use of methods of descriptive geometry is offered. Practical recommendations on accounting for the influence of vertical distortions on forces in the bars of the structure are given. An example of calculation for vertical distortion with the use of descriptive geometry methods and also the matrix unit of linear algebra is made. The ways of further development of the methodology applied to the spatial constructions, based on more points than four, are outlined.
Key words: structural design, inspection, defects, vertical distortion, redistribution of efforts.
1. Trofimov V. I., Begun G. B. Strukturnye konstruktsii [Structural design]. Moscow, Stroyizdat Publ., 1972. 266 p. (In Russian).
2. Khromets Yu. N. Sovremennye konstruktsii promyshlennykh zdaniy [Modern design of industrial buildings]. Moscow, Stroyizdat Publ., 1982. 347 p. (In Russian).
3. Mengerinhausen Raumfachwerke aus Staben und Knoten. Wiesbaden und Berlin: Bauverlag GMBH, 1975. 335 p.
4. Butner, Stenker Metalleichtbauten Ebene Raumstabwerke. Berlin, VEB Verlag fŘr Bauwesen. 1970. 224 p.
5. Demidov N. N. Features of the actual work of structural designs with bolted joints, their examination and strengthening. Vestnik MGOU, 2009, no. 1(3), pp. 34-43. (In Russian).
6. Demidov N. N. Assessment of influence of vertical oblignity of supporting units of steel spac-grid structures. Promyshlennoe i grazhdanskoe stroitel'stvo, 2013, no. 12, pp. 82-83. (In Russian).
7. Bel'skiy M. R. Usilenie metallicheskikh konstruktsiy pod nagruzkoy [Strengthening of metallic structures under load]. Kiev, Budivel'nik Publ., 1975. 120 p. (In Russian).
- On the Need to Determine Optimal Parameters for Room Temperature in Building Regulations RT 23-02-2009 źThermal Protection of Buildings╗ According to Indices of Thermal Comfort PMV and PPD
- UDC 628.87
Shuhrat Z. USMONOV, e-mail: firstname.lastname@example.org
Moscow State University of Civil Engineering, Yaroslavskoye shosse, 26, Moscow 129337, Russian Federation; Khujand Polytechnical Institute of Tajik Technical University, ul. Lenina, 26, Khujand 735700, Tajikistan
Abstract. Issues of the integral assessment of microclimatic conditions within the indoor environment on the basis of the analytical determination and interpretation of thermal comfort using calculation of the indices PMV and PPD are considered. This method of temperature conditions evaluation is based on the need to ensure the heat balance of the human with due regard for the complex of such factors as temperature, humidity, velocity of air motion, mean radiant temperature, clothing, and physical activity. The result of the evaluation of microclimatic conditions is a prediction of the human sensation of heat index ("Predicted Mean Vote (PMV)" and the level of his discomfort (indicator "Predicted Percentage of Dissatisfaction (PPD)". Formulae for calculating the thermal comfort indices PMV and PPD are presented. This article offers results of the analysis of microclimatic parameters of the internal environment using a comprehensive, integral assessment with the use of indexes PMV and PPD, on the basis of which the conclusion about the need to determine the optimal parameters of indoor temperature in the Building Regulations "Thermal Protection of Buildings" according to thermal comfort indices PMV and PPD is made. Examples of the recommended categories for the design of heating and cooling of buildings are presented. The estimated average internal temperature of the building adopted for the calculation of enclosing structures of residential buildings for all regions of the Republic of Tajikistan in Building Regulations RT "Thermal Protection of Buildings" is within the range of 20-22 ░C that does not correspond to the extreme conditions of the dry hot climate of the Northern Tajikistan. On the basis of mathematical simulation of climatic conditions of this region the optimal temperatures of indoor environment in the heating and cooling periods have been determined.
Key words: microclimate, heat comfort, thermal conditions, dry hot climate, indexes of heat comfort PMV and PPD.
1. Fanger P. O. Thermal comfort analysis and applications in environmental engineering. McGraw-Hill, New York, 1970, 244 p.
2. Myagţv M. S., Guberskiy Y. D., Kononova L. I., Litzkevich V. ╩. Gorod, architectura, chelovec i climat [Urban, architecture, human and climate]. ╠oscow, Architectura-S Publ., 2007. 344 p. (In Russian).
3. Usmonov Sh. Z. Simulation of Energy Demand for Heating and Cooling of a 5-Storey Residential Building and Evaluation of Thermal Conditions Based on PMV and PPD Thermal Comfort Indices. Vestnik MGSU, 2013, no. 10, pp. 216-229. (In Russian).
4. Olesen B. W. Information paper on EN 15251. Indoor environmental input parameters for design and assessment of Energy performance of buildings addressing indoor air quality, thermal environment, lighting and acoustics. Energy Performance of Buildings GENSE, 15. 02.2010, pp. 1-7.
5. Usmonov Sh. Z. Identification of Thermal Comfort Zone on Residential Premises in the Dry Hot Climate of Central Asia. Vestnik MGSU, 2013, no. 7, pp. 152-156. (In Russian).
- Development of Methodology for Defining the Index of Combination of Construction Processes with the Use of Minimum Technological Volume
- UDC 69.05:658.512.626
Zinur R. MUKHAMETZYANOV, e-mail: email@example.com
Ufa State Petroleum Technological University, ul. Kosmonavtov, 1, Ufa 450062, Russian Federation
Abstract. Existing methods for defining the degree of combination of processes are analyzed. On the basis of this analysis conclusions about the necessity of development of the universal method for defining the index of combination with the help of which it is possible to describe the dependences of continuous, flow- line and parallel realization of processes, and reflect the optimum borders of process combination are made. In the course of formation of a model for defining optimum borders of processes combination it is reasonable to use the directed graph for the description of which a certain process and variety of processes immediately preceding the process, and the type of connection as well as the parameter of minimal technological volume should be known. The proposed calculation of the value of the maximal displacement of the beginning of executing and preceding processes is the final stage in the algorithm of defining the index of combination of building processes with the use of the minimal technological volume.
Key words: combination of construction processes, minimum technological volume, organizational-technological design, modeling, directed graph, calculated maximal displacement.
1. Mukhametzyanov Z. R., Razyapov R. V. Accounting technological factors for identifying the possibility of combining construction works. Promyshlennoe i grazhdanskoe stroitel'stvo, 2013, no. 11, pp. 86-87. (In Russian).
2. Kaplan L. M. Ekonomicheskie problemy intensifikatsii stroitel'nogo proizvodstva [Economic problems of the intensification of building production]. L. : Stroyizdat. Leningr. Otd-nie Publ., 1990. 157 p. (In Russian).
3. Mukhametzyanov Z. R. Methodology of calculation of the quantitative assessment of technological interrelations between construction processes. Nauchnyy vestnik Voronezhskogo GASU. Stroitel'stvo i arkhitektura, 2014, no. 2 (34), pp. 44-51. (In Russian). 4. Oleynik P. P., Brodsky V. I. Methods for determining the duration of construction of objects. Promyshlennoe i grazhdanskoe stroitel'stvo, 2012, no. 12, pp. 30-32. (In Russian).
5. Gusakov A. A. Problems of science and projection in matters of management of construction. Promyshlennoe stroitel'stvo, 1977, no. 11, pp. 43-45. (In Russian).
6. Mukhametzyanov Z. R., Gusev E. V. Problems of enhancement of organizational-technological models of object construction. Promyshlennoe i grazhdanskoe stroitel'stvo, 2012, no. 4, pp. 68-69. (In Russian).
7. Kharari F. Teoriya grafov. Moscow, Editorial URSS Publ., 2003. 297 p. (In Russian).
8. Nebritov B. N., Zelentsov L. B., Lazarev G. I., et al. Avtomatizatsiya resheniya zadach podgotovki stroitel'nogo proizvodstva i operativnogo upravleniya [Automation of the solving with problem of preparation of construcrion production and operating control]. Moscow, Stroyizdat Publ., 1993. 416 p. (In Russian).
9. Mukhametzyanov Z. R. Laws of interrelation of civil work as component of technology of building of objects. Privolzhskiy nauchnyy zhurnal, 2013, no. 2, pp. 52-56. (In Russian).