Научная статья на тему 'THERMAL CRACKING RESISTANCE IN MASSIVE STEEL-REINFORCED CONCRETE STRUCTURES'

THERMAL CRACKING RESISTANCE IN MASSIVE STEEL-REINFORCED CONCRETE STRUCTURES Текст научной статьи по специальности «Строительство и архитектура»

CC BY
113
19
i Надоели баннеры? Вы всегда можете отключить рекламу.
Журнал
Magazine of Civil Engineering
Scopus
ВАК
RSCI
ESCI
Ключевые слова
СТАЛЕЖЕЛЕЗОБЕТОННЫЕ КОНСТРУКЦИИ / ТЕРМОНАПРЯЖЕННОЕ СОСТОЯНИЕ / ТЕРМИЧЕСКАЯ ТРЕЩИНОСТОЙКОСТЬ / РАСЧЕТНАЯ СХЕМА / СТРОИТЕЛЬНЫЙ ПЕРИОД / STEEL-REINFORCED CONCRETE / STRESSED STATE / CRACKING RESISTANCE / ANALYTIC MODEL / CONSTRUCTION PERIOD

Аннотация научной статьи по строительству и архитектуре, автор научной работы — Bushmanova A.V., Kharchenko D.K., Semenov K.V., Barabanshchikov Yu.G., Korovina V.K.

The work is dedicated to research of the thermal crack resistance in massive steel-reinforced concrete structures in construction period. The article examines the results of the analysis of the thermal stress state, which occurs in massive steel-reinforced concrete column. The steel part of the column is represented by a system of cross UC-beams. The study was conducted with using analytical models, which include the factor of steel profiles availability in comparison with simplified methods. Authors established that calculations of thermal stresses state of massive steel-reinforced concrete structures in construction period should be carried out with using analytical models, which assumed accounting of the availability steel profiles in cross-section of the column. Structure heating and tension stresses are significantly lower in this case. With all characteristics averaged, maximum tension stresses are less than real by 50.9% and thickness of the thermal insulation is less than required 5 times. Was defined, that calculations of thermal crack resistance in construction period of steel-reinforced concrete structures by simplified analytical model (which assume absence of steel profiles in cross-section of the column) lead to significant errors.

i Надоели баннеры? Вы всегда можете отключить рекламу.
iНе можете найти то, что вам нужно? Попробуйте сервис подбора литературы.
i Надоели баннеры? Вы всегда можете отключить рекламу.

ТЕРМИЧЕСКАЯ ТРЕЩИНОСТОЙКОСТЬ МАССИВНЫХ СТАЛЕЖЕЛЕЗОБЕТОННЫХ КОНСТРУКЦИЙ

Работа посвящена исследованию термической трещиностойкости массивных сталежелезобетонных конструкций в строительный период. В статье рассматриваются результаты анализа термонапряженного состояния массивной сталежелезобетонной колонны, стальная часть которой представлена системой перекрестных двутавров. Исследование проводилось с использованием расчетной схемы, предполагающей учет наличия в поперечном сечении стальных профилей, а также по упрощенным методикам. Авторами установлено, что расчеты термонапряженного состояния массивных сталежелезобетонных конструкций в строительный период следует проводить с использованием расчетных схем, предполагающих учет наличия в поперечном сечении стальных профилей: разогрев конструкции и растягивающие напряжения существенно меньше. Показано, что при осреднении всех характеристик максимальные растягивающие напряжения меньше реальных на 50.9 %, а толщина теплоизоляции меньше реально требуемой в 5 раз. Определено, что упрощенная расчетная схема (предполагающая отсутствие стальных профилей в поперечном сечении) также приводит к существенным погрешностям.

Текст научной работы на тему «THERMAL CRACKING RESISTANCE IN MASSIVE STEEL-REINFORCED CONCRETE STRUCTURES»

doi: 10.18720/MCE.79.5

Thermal cracking resistance in massive steel-reinforced

concrete structures

Термическая трещиностойкость массивных сталежелезобетонных конструкций

A.V. Bushmanova, Студент А.В. Бушманова,

D K Kharchenko студент Д.К. Харченко,

KS. Semenov канд. техн. наук, доцент К.В. Семенов,

YuG. Barabanshchikov д-р техн. наук, профессор

VK Korovina Ю.Г. Барабанщиков,

A.V. Dernakova, студент В.К. Коровина,

Peter the Great St. Petersburg Polytechnic студент А.В. Дернакова,

Ш^/ъ^ St. petersburg, Russia Санкт-Петербургский политехнический

университет Петра Великого, Санкт-Петербург, Россия

Key words: steel-re in forced concrete; stressed Ключевые слова: сталежелезобетонные state; cracking resistance; analytic model; конструкции; термонапряженное состояние; construction period термическая трещиностойкость; расчетная

схема; строительный период

Abstract. The work is dedicated to research of the thermal crack resistance in massive steel-reinforced concrete structures in construction period. The article examines the results of the analysis of the thermal stress state, which occurs in massive steel-reinforced concrete column. The steel part of the column is represented by a system of cross UC-beams. The study was conducted with using analytical models, which include the factor of steel profiles availability in comparison with simplified methods. Authors established that calculations of thermal stresses state of massive steel-reinforced concrete structures in construction period should be carried out with using analytical models, which assumed accounting of the availability steel profiles in cross-section of the column. Structure heating and tension stresses are significantly lower in this case. With all characteristics averaged, maximum tension stresses are less than real by 50.9% and thickness of the thermal insulation is less than required 5 times. Was defined, that calculations of thermal crack resistance in construction period of steel-reinforced concrete structures by simplified analytical model (which assume absence of steel profiles in cross-section of the column) lead to significant errors.

Аннотация. Работа посвящена исследованию термической трещиностойкости массивных сталежелезобетонных конструкций в строительный период. В статье рассматриваются результаты анализа термонапряженного состояния массивной сталежелезобетонной колонны, стальная часть которой представлена системой перекрестных двутавров. Исследование проводилось с использованием расчетной схемы, предполагающей учет наличия в поперечном сечении стальных профилей, а также по упрощенным методикам. Авторами установлено, что расчеты термонапряженного состояния массивных сталежелезобетонных конструкций в строительный период следует проводить с использованием расчетных схем, предполагающих учет наличия в поперечном сечении стальных профилей: разогрев конструкции и растягивающие напряжения существенно меньше. Показано, что при осреднении всех характеристик максимальные растягивающие напряжения меньше реальных на 50.9 %, а толщина теплоизоляции меньше реально требуемой в 5 раз. Определено, что упрощенная расчетная схема (предполагающая отсутствие стальных профилей в поперечном сечении) также приводит к существенным погрешностям.

1. Introduction

Most of massive steel-reinforced concrete structures are made of rigid steel profiles placed inside of reinforced concrete part of the structure [1-3]. Such kinds of structures are usually used for designing massive beam system, columns, and pillars. During the construction period, massive concrete and reinforced concrete structures may suffer from hard cracking [4-10]. In general, the cause of this phenomenon should be called irregular temperature fields at the body of the structure [11-17]. These fields generate significant tensile surface thermal stresses [18-26].

Many researches are devoted to the analysis of possible methods of steel and concrete calculations: definition of the analytical model [27-31]; estimation of different affects, such as concreting conditions, characteristics of materials, application of various technologies [32-36]; etc.

According to the paper [27], material modeling plays a major role in how reinforced concrete beams and frames react to temperature variation. Hence, the nonlinear temperature gradient, which is the realistic profile, is important to implement in the analysis.

In the paper [29], the ultimate strength behavior of the RC beams under different low temperatures is investigated by the methods of experiment, analysis and evaluation. The accuracies of the analytical models and FEM simulations were checked through validations of the predictions by different models against the test results.

In the article [35], a fibre beam element is perceived as a degenerated solid element, and for the last an unified concrete constitutive model is proposed. Beam/column members with a wide range of shear span-to-depth ratios can be simulated with the degenerated solid element considering normal-shear interaction.

Structural calculation methods involve usage of structural models made with certain simplifications that greatly facilitate the calculation. Calculation with a wrong structural model cannot be valid qualitative.

For the foregoing reasons, the vital task is to estimate the necessity of steel elements' presence in structure's cross-section model for the construction period. Since the presence or absence of steel elements in calculation of thermal crack resistance may cause a significant distortion of the real thermal stresses diagram while calculation with an incorrectly chosen structural model cannot be valid qualitative, even when using the most accurate methods.

The purpose of article is to estimate the necessity of steel elements' presence in structure's cross-section calculations of thermal crack resistance in massive steel-reinforced concrete structures for the construction period. These calculations are partly carried out by simplified method. It is important to identify possible mistakes in this approach to calculation.

As initial data (thermophysical and stress-related characteristics of concrete, cement heat radiation) the results or research, obtained in laboratory "Polytech-SKiM-Test" in CUBS department by Professor Y.G. Barabanschikov were accepted.

2. Methods and Materials

This paper demonstrates calculation of stressed state with the help of TERM software developed by the Institute of Civil Engineering at the Peter the Great St.Petersburg Polytechnic University [23]. This software calculates nonstationary fields of temperature and thermal stresses in slabs.

In order to estimate the cracking resistance of the concrete column, we would use the deformation criterion suggested by P.I. Vasiliev [26]. According to this criterion, concrete elongation deformations, determined in view of the concrete creep factor and variable deformation modulus, should not exceed the ultimate concrete elongation.

The article examines the results of the analysis of the thermal stress state in construction period, which occurs in massive steel-reinforced concrete column (Figure 1) with dimension in cross-section 1500 x 1500mm. The steel part of the column is represented by a system of cross-UC beams.

Figure 1. The steel-reinforced concrete column

The research was carried out in three principal analytical models:

- The first analytical model implied a simplified approach, which means it did not take into account the presence of metal profiles in cross-section of the column. The entire cross-section of the column should be considered to consist of concrete. The calculations are made for the cross-section quarter (the symmetry of the section along the horizontal and vertical axes is used).

- The second analytical model implied accurate estimation of the availability of the steel profiles -UC-beams. The calculations are made for the cross-section quarter (Figure 2) (the symmetry of the section along the horizontal and vertical axes is used).

Figure 2. Analytical model

- The third analytical model implied averaging of material characteristics within the limits of the column cross-section and subsequent use of simplified model with homogeneous medium.

Consider B80 steel-reinforced concrete column the cement consumption of 450 kg/m3 constructed in summer. Thermal and physical characteristics of the concrete B80 are defined by the concrete thermal conductivity A =2.67 W/(m0C) and thermal capacity c = 1.0 kJ/(kg0C). For modulus of concrete deformation Emax = 45000 kg/cm2, a = -0.37, y = 0.72 [22]. Thermal and physical characteristics of the steel are defined by the steel thermal conductivity A =45 W/(m-°C) and thermal capacity c = 0.48 kJ/(kg0C). The reinforcing steel is assumed to be elastic-perfectly plastic material in both tension and compression with elasticity modulus E = 2*105 MPa and Poisson's ratio equal to 0.2.

The heat dissipation process follows the I.D. Zaporozhets equation [12].

Qt 00 = Qmax<l -

1 + a2

L

J FQ[T(T)dT]

(1)

The equation parameters I.D. Zaporozhets gets from experimental evidence on concrete heat dissipation [20] Qmax = 157500 kJ/m3, A20 = 1.97 x 10-6 c-1.

The following technological specifications of concrete pouring were taken into account: the concrete mix temperature is 15 0C and air temperature is 15 0C. Primary there was no thermal insulation on the surface of the column. Then the required thickness of thermal insulation was selected to provide crack resistance.

3. Results and Discussion

3.1. Results of applying the first analytical model Temperature fields and stress direction fields in cross-section of the column are mentioned below. Moreover, the analysis of possible cracking pattern for the most dangerous moments has been conducted. The maximum of the column tension surface stresses occurs at the first day after concreting. This stresses are equal 23.8 kg/cm2. Temperature maximum in the cross-section at the first day was 57.1 0C.

Figure 3. Thermal fields in section of the column at the first day

-14.7 -9.9 -5.1 -.3 4.5 9.3 14.1 18.9 23.7 28.5 kg/cm2

Figure 4. Stress direction fields in section of the column at the first day

Figure 5. Stress cracks position at the first day

m-1

on the edge surface - in the center

Figure 6. Graphs of changing temperatures in section of the column

To provide full crack resistance of the column during construction period a covering of surfaces with special thermal insulation requires pred = 3.24 W/m20C (pred match to the thermal insulation thickness 8 mm, using thermal insulation with A = 0.03 W/m0C).

3.2. Results of applying the second analytical model The maximum of the column tension surface stresses occurs at the first day after concreting. This stresses are equal a = 17.2 kg/cm2. Temperature maximum in the cross-section at the first day was 40.2 0C.

12.5 15.7 19.0 22.2 25.4 28.7 31.9 35.2 38.4 41.7

Figure 7. Thermal fields in section of the column at the first day

-45.6 -38.2 -30.9 -23.5 -16.2 -8.S -1.5 5.9 13.3 20.6 kg/cm2

Figure 8. Stress direction fields in section of the column at the first day

Stress cracks position on the X-axis 1 sut

Without crack I With crack

Figure 9. Stress cracks position at the first day

Changing temperatures in ttie center and on the edge surface of the column

--------------------

j -----. —--------— h—--------

D 1 2 3 4 5 6 7 S 9 1D 11 12 13 14 15 16 17 1S 15 20 21

Time, days

- on the edge surface - In tiie center

Figure 10. Graphs of changing temperatures in section of the column

To provide full crack resistance of the column in construction period, a covering of surfaces with special thermal insulation requires pred = 4.92 W/m20C (pred match to the thermal insulation thickness 5 mm using thermal insulation with A = 0.03 W/m0C).

3.3. Results of applying the third analytical model

When all thermophysical characteristics of steel and concrete have been averaged, the maximum of the column tension surface stresses at the first day after concreting were equal a = 11.4 kg/cm2. Temperature maximum in the cross-section at the first day was equal 41.50C. Required thickness of the thermal insulation was 1 mm (pred = 13.2 W/m20C).

If the characteristics of heat release of materials were averaged, then maximum tension surface stresses of the column would occur at the first day after concreting and would be equal a = 21.0 kg/cm2. Maximum temperature in the cross-section at the first day was equal 53.7 0C. Required thickness of the thermal insulation was 7 mm (pred = 3.7 W/m20C).

3.4. Discussion

Thus, according to the paper [27, 28] it is important to possess knowledge of aspects having the greatest influence on data calculated while researching the thermal cracking resistance of massive concrete and reinforced structures. Calculation with an incorrectly chosen structural model or calculation implying a simplified approach could not be valid qualitative [30-32, 35, 36]. According to studies, those calculations of thermal stresses state of the massive steel-reinforced concrete structures in construction period by analytical models, which include the factor of steel profiles availability, are more appropriate and accurate in comparison with simplified methods.

4. Conclusion

The results of the experiments conducted lead us to the following conclusions:

1. The calculations of thermal crack resistance in construction period of steel-reinforced concrete structures by simplified analytical model (which assume absence of steel profiles in cross-section of the column) lead to significant errors. In comparison with the real situation (the second analytical model), maximum tension stresses from the simplified case more on 27.7 %. Required thickness of the thermal insulation is too high, which means that the first analytical model is economically unreasonable.

2. Averaging of thermophysical characteristics of steel and concrete in cross-section of the column also does not bring a satisfactory result. With all characteristics averaged, maximum tension stresses are less then real by 50.9% and thickness of the thermal insulation is less than required 5 times. Consequently, the calculation by this model may lead to the appointment of an incorrect stowage technique and cracking with subsequent full or partial destruction of the structure. When we are only averaging heat release characteristic, like in the first case, stresses rise and required thickness is too high.

3. The calculations of thermal stresses state of massive steel-reinforced concrete structures in construction period should be carried out with using analytical models, which assumed accounting of the

availability steel profiles in cross-section of the column. Structure heating and tension stresses are significantly lower in this case. This calculation should be called the most effective, economically feasible and structurally accurate.

References

1. Kashevarova G.G., Martirosjan A.S., Travush V.I. Raschetno-jeksperimental'noe issledovanie processa razrushenija svjazej sceplenija pri vdavlivanii sterzhnja zhestkoj armatury v beton [Computational and experimental study of the process of destruction of bonding bonds when pressing a rod of rigid reinforcement into concrete]. Vestnik permskogo nacional'nogo issledovatel'skogo politehnicheskogo universiteta. Mehanika. 2016. No. 3. Pp. 62-75.

2. Seryh I.R., Chernysheva E.V. Stalebeton v sovremennom stroitel'stve [Steel concrete in modern construction]. Naukoemkie tehnologii i innovacii: sb. dokl. Jubilejnoj Mezhdunar. nauch.-prakt. konf., posvjashhennoj 60-letiju BGTU im. V.G.Shuhova. Belgorod: Izd-vo BGTU, 2014. Vol. 2. Pp. 112-115.

3. Seryh I.R., Degtjar' A.N., Naumov A.E. Jeffekt primenenija stalebetonnyh kolonn [The effect of using steel-reinforced concrete columns]. Vestnik BGTU im. V.G. Shuhova. 2014. No. 5. Pp. 63-66.

4. Holt E., Leivo M. Cracking risks associated with early age shrinkage. Cement and Concrete Composites. 2004. No. 26(5). Pp. 521-530.

5. Larson M. Thermal crack estimation in early age concrete-models and methods for practical application. Division of Structural Engineering, Lulea University of Technology, Doctoral Thesis, 2003. 190 p.

6. Miyazawa S., Koibuchi K., Hiroshima A., Ohtomo T., Usui T. Control of thermal cracking in mass concrete with blast-furnace slag cement. Concrete Under Severe Conditions. 2010. No. 7-9. Pp. 1487-1495.

7. Se-Jin J. Advanced Assessment of Cracking due to Heat of Hydration and Internal Restraint. ACI Materials Journal. 2008. No. 105. Pp. 325-333.

8. Shengxing W., Donghui H. Estimation of cracking risk of concrete at early age based on thermal stress analysis. Journal of Thermal Analysis and Calorimetry. 2011. Vol. 105. No. 1. Pp. 171-186.

9. Zhang Z., Zhang X., Wang X., Zhang T. Merge concreting and crack control analysis of mass-concrete base slab of nuclear power plant. Applied Mechanics and Materials. 2011. No. 94-96. Pp. 2107-2110.

10. Lee Y., Kim J-K. Numerical analysis of the early age behavior of concrete structures with a hydration based microplane model. Computers and Structures. 2009. No. 7. Pp. 1085-1101.

11. Gorshkov A., Vatin N., Nemova D., Tarasova D. The brickwork joints effect on the thermotechnical uniformity of the exterior walls from gas-concrete blocks. Applied Mechanics and Materials. 2015. No. 725-726. Pp. 3-8.

12. Zaporozhets I.D., Okorokov S.D., Pariyskiy A.A., Teplovydeleniye betona [Heat Liberation by concrete]. Leningrad-Moscow: Stroyizdat, 1966. 316 p. (rus)

13. Ginzburg S.M., Sheynker N.Y., Dobretsova I.V. , Voznesenskaya N.V., Issledovaniya po termike betonnykh sooruzheniy [Studies of thermal processes in concrete structures]. Proc. of the VNIIG. 2011. Vol. 263. Pp. 87-97. (rus)

14. Korsun V., Vatin N., Franchi A., Korsun A., Crespi P., Mashtaler S. The strength and strain of high-strength concrete elements with confinement and steel fiber reinforcement including the conditions of the effect of elevated temperatures. Procedia Engineering. 2015. Vol. 117. Pp. 970-979.

15. Jaafar M.S, et.al. Development of finite element computer code for thermal analysis of roller compacted concrete

Литература

1. Кашеварова Г.Г., Мартиросян А.С., Травуш В.И. Расчетно-экспериментальное исследование процесса разрушения связей сцепления при вдавливании стержня жесткой арматуры в бетон // Вестник пермского национального исследовательского политехнического университета. Механика. 2016. № 3. С. 62-75.

iНе можете найти то, что вам нужно? Попробуйте сервис подбора литературы.

2. Серых И.Р., Чернышева Е.В. Сталебетон в современном строительстве // Наукоемкие технологии и инновации: сб. докл. Юбилейной Междунар. науч.-практ. конф., посвященной 60-летию БгТу им. В.Г. Шухова. Белгород: Изд-во БГТУ, 2014. Ч. 2. С. 112-115.

3. Серых И.Р., Дегтярь А.Н., Наумов А.Е. Эффект применения сталебетонных колонн // Вестник БГТУ им. В.Г. Шухова. 2014. № 5. С. 63-66.

4. Holt E., Leivo M. Cracking risks associated with early age shrinkage // Cement and Concrete Composites. 2004. № 26(5). Pp. 521-530.

5. Larson M. Thermal crack estimation in early age concrete-models and methods for practical application. Division of Structural Engineering, Lulea University of Technology, Doctoral Thesis, 2003. 190 p.

6. Miyazawa S., Koibuchi K., Hiroshima A., Ohtomo T., Usui T. Control of thermal cracking in mass concrete with blast-furnace slag cement // Concrete Under Severe Conditions. 2010. № 7-9. Pp. 1487-1495

7. Se-Jin J. Advanced Assessment of Cracking due to Heat of Hydration and Internal Restraint // ACI Materials Journal. 2008. № 105. Pp. 325-333.

8. Shengxing W., Donghui H. Estimation of cracking risk of concrete at early age based on thermal stress analysis // Journal of Thermal Analysis and Calorimetry. 2011. Vol. 105. № 1. Pp. 171-186.

9. Zhang Z., Zhang X., Wang X., Zhang T. Merge concreting and crack control analysis of mass-concrete base slab of nuclear power plant // Applied Mechanics and Materials. 2011. № 94-96. Pp. 2107-2110.

10. Lee Y., Kim J-K. Numerical analysis of the early age behavior of concrete structures with a hydration based microplane model // Computers and Structures. 2009. № 87. Pp. 1085-1101.

11. Gorshkov A., Vatin N., Nemova D., Tarasova D. The Brickwork Joints Effect on the Thermotechnical Uniformity of the Exterior Walls from Gas-Concrete Blocks // Applied Mechanics and Materials. 2015. № 725-726. Pp. 3-8.

12. Запорожец И.Д., Окороков С.Д., Парийский А.А. Тепловыделение бетона. М.: Стройиздат, 1966. 316 с.

13. Гинзбург С.М., Шейнкер Н.Я., Добрецова И.В., Вознесенская Н.В. Исследования по термике бетонных сооружений // Известия ВНИИГ. 2011. Т. 263. С. 87-97.

14. Korsun V., Vatin N., Franchi A., Korsun A., Crespi P., Mashtaler S. The Strength and Strain of High-strength Concrete Elements with Confinement and Steel Fiber Reinforcement Including the Conditions of the Effect of Elevated Temperatures // Procedia Engineering. 2015. Vol. 117. Pp. 970-979.

15. Jaafar M.S, et.al. Development of finite element computer code for thermal analysis of roller compacted concrete dams // Advances in Engineering Software. 2007. № 38. Pp. 886-895.

16. Kim S.G. Effect of heat generation from cement hydration on mass concrete placement, Civil Engineering, Iowa State University, Master of Science Thesis, 2010. 126 p.

17. Пуляев И.С. Методы регулирования теплового режима бетона при ускоренном возведении железобетонных

dams. Advances in Engineering Software. 2007. No. 38. Pp. 886-895.

16. Kim S.G. Effect of heat generation from cement hydration on mass concrete placement. Civil Engineering, Iowa State University, Master of Science Thesis, 2010. 126 p.

17. Pulyayev I.S. Metody regulirovaniya teplovogo rezhima betona pri uskorennom vozvedenii zhelezobetonnykh elementov pilonov vantovykh mostov. Diss. na soisk. uchen. step. kand. teh. nauk: Spets 05.23.05 [Methods of concrete thermal regime regulation during accelerated construction of reinforced concrete pier elements in cable bridges. Cand. Tech. sci. diss.]. Moscow: 2010. 207 p. (rus)

18. Korsun V.I., Korsun A.V. Vliyanie masshtabnogo faktora i povyshennykh temperatur na prochnost' i deformatsii vysokoprochnogo modifi tsirovannogo betona [The Influence of the Scale Effect and high Temperatures on the Strength and Strains of High Performance Concrete]. Vestnik MGSU. 2014. No. 3. Pp. 179—188.

19. Korsun V.I. Napryazhenno-deformirovannoe sostoyanie zhelezobetonnykh konstruktsiy v usloviyakh temperaturnykh vozdeystviy [Stress and Strain State of Reinforced Concrete Structures under Thermal Impacts]. Makeevka, DonGASA Publ., 2003, 153 p.

20. Chekalkin A.V. Termonapryazhennoe sostoyanie betona fundamenta turboagregata LAES-2 v stroitelnyi period: Dis. na soisk. uchen. step. magistra: Spets. 270800.68.09 [Thermo-stressed state of concrete foundation of turbine unit of LNPP-2 in construction period. M. Sci. Eng. Tech], URL:http://elib.spbstu.ru/dl/2/3330.pdf/view, 2014 (rus)

21. Yamkova E.V. Treschinostoikost i termonapryazhennoe sostoyanie massivnoy fundamentnoy plity LAES-2: Dis. na soisk. uchen. step. magistra: Spets. 08.04.01.09 [Thermal crack resistance and thermo-stressed state of massive fundamental slab of LNPP-2. M. Sci. Eng. Tech] URL: http://elib.spbstu.ru/dl/2/v16-1267.pdf/view, 2015 (rus)

22. Malinin N.A. Issledovaniye termonapryazhennogo sostoyaniya massivnykh betonnykh konstruktsiy s peremennymi deformativnymi kharakteristikami: Diss. na soisk. uchen. step. kan. teh. nauk: Spets 05.23.01. [Research of thermal stressed state of mass concrete structures with changing deformations characteristics. Cand. tech. sci. diss.]. Leningrad, 1977. 186 p. (rus)

23. Semenov K.V. Temperaturnoye i termonapryazhennoye sostoyaniye blokov betonirovaniya korpusa vysokogo davleniya v stroitelnyy period: Dis. na soisk. uchen. step. kan. teh. nauk: Spets 05.23.01 [Temperature and thermal stressed state of concreting blocks in a high pressure shell during the building period]. Leningrad, 1990. 156 p. (rus).

24. Krat T.Y., Rukavishnikova T.N. Otsenka temperaturnogo rezhima i termonapryazhennogo sostoyaniya blokov vodosliva pri razlichnykh usloviyakh betonirovaniya [Assessment of temperature regime and thermo-stressed state of spillway units at different concreting conditions]. Proc. of the VNIIG. 2007. Vol. 248. Pp. 77-85. (rus)

25. Tsybin A.M. Programma bystrogo rascheta termonapryazhennogo sostoyaniya sistemy narashchivayemykh betonnykh blokov [Program for rapid calculation routine for thermal stress state of a system of concrete blocks under construction]. Proc. of the VNIIG. Vol. 237. Pp. 69-76.

26. Vasilyev P.I., Ivanov D.A., Kononov Yu.I., Semenov K.V., Starikov O.P. Raschetnoye obosnovaniye razmerov blokov i posledovatelnosti betonirovaniya korpusa reaktora VG-400 s proverkoy na modeli 1/5 naturalnoy velichiny [Calculation analysis of concreting blocks and VG-400 reactor shell concreting sequence using a 1/5 scale model]. Problems of atomic science and technology. 1988. No. 1. Pp. 62-68. (rus)

27. El-Tayeb E.H., El-Metwally S.E., Askar H.S., Yousef A.M. Thermal analysis of reinforced concrete beams and frames. HBRC Journal. 2017. Vol. 13. No. 1. Pp. 8-24.

элементов пилонов вантовых мостов: дисс. на соиск. учен. степ. к. т. н.: Спец. 05.23.05. М., 2010. 207 с.

18. Корсун В.И., Корсун А.В. Влияние масштабного фактора и повышенных температур на прочность и деформации высокопрочного модифицированного бетона // Вестник МГСУ. 2014. № 3. С. 179-188.

19. Корсун В.И. Напряженно-деформированное состояние железобетонных конструкций в условиях температурных воздействий. Макеевка: ДонГАСА, 2003. 153 с.

20. Чекалкин А.В. Термонапряженное состояние бетона фундамента турбоагрегата ЛАЭС-2 в строительный период: Дис. на соиск. учен. степ. магистра: Спец 08.04.01 [Электронный ресурс]: Систем. требования: Google Chrome. URL: http://elib.spbstu.rU/dl/2/3330.pdf/view (дата обращения: 5.09.2016)

21. Ямкова Е.В. Трещиностойкость и термонапряженное состояние массивной фундаментной плиты ЛАЭС-2: Дис. на соиск. учен. степ. магистра: Спец 08.04.01 [Электронный ресурс]: Систем. требования: Google Chrome. URL: http://elib.spbstu.rU/dl/2/v16-1267.pdf/view (дата обращения 5.09.2016)

22. Малинин Н.А. Исследование термонапряженного состояния массивных бетонных конструкций с переменными деформативными характеристиками: Дис. на соиск. учен. степ. к. т. н.: Спец. 05.23.01. Л., 1977. 186 с.

23. Семенов К.В. Температурное и термонапряженное состояние блоков бетонирования корпуса высокого давления в строительный период: Дис. на соиск. учен. степ. к. т. н.: Спец. 05.23.01. Л., 1990. 156 с.

24. Крат Т.Ю., Рукавишникова Т.Н. Оценка температурного режима и термонапряженного состояния блоков водослива при различных условиях бетонирования // Известия ВНИИГ. 2007. Т. 248. С. 77-85.

25. Цыбин А.М. Программа быстрого расчета термонапряженного состояния системы наращиваемых бетонных блоков // Известия ВНИИГ. 2000. Т. 237. С. 69-76.

26. Васильев П.И., Иванов Д.А., Кононов Ю.И., Семенов \ К.В., Стариков О.П. Расчетное обоснование размеров блоков и последовательности бетонирования корпуса реактора VG-400 с проверкой на модели 1/5 натуральной величины // Вопросы атомной науки и техники. 1988. № 1. С. 62-68.

27. El-Tayeb E.H., El-Metwally S.E., Askar H.S., Yousef A.M. Thermal analysis of reinforced concrete beams and frames // HBRC Journal 2017. Vol. 13. № 1. Pp. 8-24.

28. Васильев А.А. Оценка прочности бетона и ее прогнозирование для бетонных и железобетонных конструкций // Вестник гомельского государственного технического университета им. П.О. Сухого. 2005. № 4(23). С. 16-22.

29. Плевков В.С., Малиновский А.П., Балдин И.В. Оценка прочности и трещиностойкости железобетонных конструкций по российским и зарубежным нормам // Вестник томского государственного архитектурно-строительного университета. 2013. № 2(39). С. 144-153.

30. Yan J.-B., Xie J. Behaviours of reinforced concrete beams under low temperatures // Construction and Building Materials. 2017. Vol. 141. Pp. 410-415.

31. Lantsoght E.O.L., de Boer A., der Veen C. Distribution of peak shear stress in finite element models of reinforced concrete slabs // Engineering Structures. 2017. Vol. 148. Pp. 571-583.

32. Hu B., Wu Y.-F. Quantification of shear cracking in reinforced concrete beams // Engineering Structures. 2017. Vol. 147. Pp. 666-678.

33. Moallemi S., Pietruszczak S. Analysis of localized fracture in 3D reinforced concrete structures using volume

28. Vasil'ev A.A. Ocenka prochnosti betona i ee prognozirovanie dlja betonnyh i zhelezobetonnyh konstrukcij [Evaluation of the strength of concrete and its prediction for concrete and reinforced concrete structures]. Vestnik gomel'skogo gosudarstvennogo tehnicheskogo universiteta im. P.O. Suhogo. 2005. No. 4(23). Pp. 16-22. (rus)

29. Plevkov V.S., Malinovskij A.P., Baldin I.V. Ocenka prochnosti i treshhinostojkosti zhelezobetonnyh konstrukcij po rossijskim i zarubezhnym normam [Evaluation of strength and fracture toughness of reinforced concrete structures according to Russian and foreign norms] Vestnik tomskogo gosudarstvennogo arhitekturno-stroitel'nogo universiteta. 2013. No. 2(39). Pp. 144-153. (rus)

30. Yan J.-B., Xie J. Behaviours of reinforced concrete beams under low temperatures. Construction and Building Materials. 2017. Vol. 141. Pp. 410-415.

31. Lantsoght E.O.L., de Boer A., der Veen C. Distribution of peak shear stress in finite element models of reinforced concrete slabs. Engineering Structures. 2017. Vol. 148. Pp. 571-583.

32. Hu B., Wu Y.-F. Quantification of shear cracking in reinforced concrete beams // Engineering Structures. 2017. Vol. 147. Pp. 666-678.

33. Moallemi S., Pietruszczak S. Analysis of localized fracture in 3D reinforced concrete structures using volume averaging technique. Finite Elements in Analysis and Design. 2017. Vol. 125.Pp. 41-52.

34. Chen W., Hao H., Chen S. Numerical analysis of prestressed reinforced concrete beam subjected to blast loading. Materials and Design. 2015. Vol. 65. Pp. 662-674.

35. Long X., Bao J.Q., Tan K.H., Lee C.K. Numerical simulation of reinforced concrete beam/column failure considering normal-shear stress interaction. Engineering Structures. 2014. Vol. 74. Pp. 32-43.

36. Dede T., Ayvaz Y. Nonlinear analysis of reinforced concrete beam with/without tension stiffening effect. Materials and Design. 2009. Vol. 30. No. 9. Pp. 3846-3851.

37. Rabczuk T., Akkermann J., Eibl J. A numerical model for reinforced concrete structures. International Journal of Solids and Structures. 2005. Vol. 42. No. 5-6. Pp. 1327-1354.

averaging technique // Finite Elements in Analysis and Design. 2017. Vol. 125. Pp. 41-52.

34. Chen W., Hao H., Chen S. Numerical analysis of prestressed reinforced concrete beam subjected to blast loading // Materials and Design. 2015. Vol. 65. Pp. 662-674.

35. Long X., Bao J.Q., Tan K.H., Lee C.K. Numerical simulation of reinforced concrete beam/column failure considering normal-shear stress interaction // Engineering Structures. 2014. Vol. 74. Pp. 32-43.

36. Dede T., Ayvaz Y. Nonlinear analysis of reinforced concrete beam with/without tension stiffening effect // Materials and Design. 2009. Vol. 30. № 9. Pp. 3846-3851.

37. Rabczuk T., Akkermann J., Eibl J. A numerical model for reinforced concrete structures // International Journal of Solids and Structures. 2005. Vol. 42. № 5-6. Pp. 1327-1354.

Aleksandra Bushmanova, +7(981)822-34-63; [email protected]

Daria Kharchenko,

+7(952)242-65-44; dashulity@gmail. com Kirill Semenov,

+7(921)781-19-57; [email protected]

Yuriy Barabanshchikov, +7(812)534-12-86; [email protected]

Victoria Korovina,

+7(911)785-54-29; [email protected]

Aleksandra Dernakova, +7(911)774-90-23; [email protected]

Александра Васильевна Бушманова, +7(981)822-34-63; эл. почта: [email protected]

Дарья Константиновна Харченко,

+7(952)242-65-44;

эл. почта: [email protected]

Кирилл Владимирович Семенов, +7(921)781-19-57; эл. почта: [email protected]

Юрий Германович Барабанщиков, +7(812)534-12-86; эл. почта: [email protected]

Виктория Константиновна Коровина, +7(911)785-54-29; эл. почта: [email protected]

Александра Вячеславовна Дернакова,

+7(911)774-90-23;

эл. почта: [email protected]

© ВиэИтапоуа А.У.,КИагсИепко й. К.,Бетепоу К.З.,ВагаЬапБЬсЫкоу Уи.С.,

Когомпа У.К.,йегпакоуа А. У.,2018

i Надоели баннеры? Вы всегда можете отключить рекламу.