75504 2712-8172 5 73 2017 1-112

RAR RUS 3-13 57191530761 0000-0002-4765-5819 Moscow State University of Civil Engineering (National Research University) Alekseytsev Anatoly aalexw@mail.ru

Moscow, Russia

Bryansk State University of Engineering and Technology Kurchenko Natalia inserpik@gmail.com Deformations of steel roof trusses under shock emergency action The problems of experimental and theoretical research on the stressed and deformed state of steel structures under emergency actions are particularly relevant. Тhis paper proposes experimental and theoretical research methodology, which is used on the basis of an example of research on a full-length truss as part of the frame for an industrial buildings workshop. Components of the stressed-strained state of the structure are determined experimentally in the course of a simulated emergency situation. As emergency impacts, this paper considers the detachment of the air-cooling unit attached to a node of the lower chord of the truss. Experimental data is gathered through the joint use of the crate system, cable sensor and PC. The finite-element modelling of the structure behavior is performed based on the direct integration of differential equations of motion of the system subject to the local dynamic effects, and a comparison of data obtained with experiments results. As a result of using the test methodology we obtained the maximum weight of technological equipment fastened to the roof truss, while ensuring its normal operation in case of an emergency related to the failure to affix the equipment. 10.18720/MCE.73.1 truss technological equipment emergency impact experiment shock effects crate system cable sensor dynamic loads displacements in time strains in time https://engstroy.spbstu.ru/article/2017.73.1/

RAR RUS 14-24 Kazan State University of Architecture and Engineering Bogdanov Ruslan bogdanov.r.r@yandex.ru 56504969400 0000-0001-8879-1190 Kazan State University of Architecture and Engineering Ibragimov Ruslan rusmag007@yandex.ru

Kazan, Russia

Process of hydration and structure formation of the modified self-compacting concrete The article reviews the research results of influence of a complex modifying agent on rheological properties of cement-water paste and cement stone strength. The article describes the processes of hydration and structure formation of cement stone, the special aspects of the phase constitution of Portland cement hydration products in the process of modifying by complex admixture. The behavior of cement hydration in composition with the complex modifying agent have been shown by means of measuring the hydrogen-ion concentration, by sedimentation, contraction and heat emission of cement suspension. There is the decreasing of the degree of cement stone hydration because of blocking action of the superplasticizing admix and hydrophobisator during the initial stage. Studying the cement stone spalls with the aid of electron microscopy has showed that there are the crystallized hydrated newgrowths with smaller dispersive capacity in composition with the complex modifying agent than the ones without introduction of admixtures. The increasing of concentration of hydrated calcium sulfoaluminate in pores and capillaries, the increasing of the specific surface area of hydrated phases both in the general structure of cement stone and in structure with regions of imperfections, the voids content decreasing lead to the material hardening. The way of cement stone structure formation in composition with the complex modifying agent is found by means of differential thermal and X-ray phase analyses. This way is shown in the composition with a complex modifying agent manifested in blocking effect SP and HP, resulting in a reduced amount of portlandite and high content of the starting phase the cement clinker, wherein the MTK is reacted with calcium hydroxide, which helps to seal material. Reduction of ettringite in the composition with a complex modifying agent is associated with precipitation of superplasticizing admix molecules on C3A particles, which limits interaction with water. 10.18720/MCE.73.2 modifying admixture superplasticizing admix hydrophobisator metakaolin self-compaсting concrete hydration https://engstroy.spbstu.ru/article/2017.73.2/

RAR RUS 25-39 National Research Moscow State Civil Engineering University Tusnina Valentina valmalaz@mail.ru Semi-rigid steel beam-to-column connections Steel frameworks are widely used construction of multistory buildings for different purposes. In the practical framework calculations, the girder-column joint connections are taken as either absolutely rigid or hinged ones. The analysis of the actual behaviour of the frame joint connections shows that they normally occupy an intermediate position in the joints classification into "rigid" and "hinged" ones, i.e. they have certain pliability. Such pliability is characterized by different grades of stiffness that depends on a specific design solution of a joint. Therefore, to avoid possible material errors, the statistical calculations of frames should consider layouts with the joints that are able to support the corresponding amount of bending moments. This article contains the results of experimental and theoretical research of the actual behaviour of the girder-column connection semi-rigid joints using ABAQUS 6.13 computing complex, which enables us to solve problems by the finite elements method with due regard to the geometrical and physical nonlinearity. We consider the design of a beam-to-column connection with connecting elements in the form of paired vertical angles bolted to the beam wall and to the column flange. Based on the comparative analysis of the results of the numerical analysis and on the experimental data, the actual behaviour of the structure has been found and the stiffness of the joint type to be considered has been determined. 10.18720/MCE.73.3 semi-rigid joint steel frame beam stiffness rotational angle support moment https://engstroy.spbstu.ru/article/2017.73.3/

RAR RUS 40-48 56426211200 0000-0002-3541-0072 Peter the Great Saint Petersburg Polytechnic University Petrichenko Mikhail fonpetrich@mail.ru

Polytechnicheskay, 29

Peter the Great Saint Petersburg Polytechnic University Subbotina Svetlana svetlana.subbotina94@mail.ru

Polytechnicheskay, 29

Peter the Great Saint Petersburg Polytechnic University Khairutdinova Faina faina.spbstu@gmail.com

Polytechnicheskay, 29

Peter the Great Saint Petersburg Polytechnic University Reich Elizaveta lisa_reich@mail.ru

Polytechnicheskay, 29

56227381900 0000-0003-2673-4566 Peter the Great Saint Petersburg Polytechnic University Nemova Darya darya.nemova@gmail.com

Polytechnicheskay, 29

Peter the Great St. Petersburg Polytechnic University Olshevskiy Vyacheslav 79119199526@yandex.ru

29 Politechnicheskaya St., St. Petersburg, 195251, Russia

AAU-2845-2020 57204362749 0000-0002-6289-325X Peter the Great St. Petersburg Polytechnic University Sergeev Vitaliy vicerector.sc@spbstu.ru

St. Petersburg, Russia

Effect of rustication joints on air mode in ventilated facade Ventilated facade is a contemporary facade system that is popular due to its energy efficiency. There are different configurations of the façade systems, among other things, various spacing between rustication joints. Cold air penetrates through them, thereby, influences air circulation. In this paper, theoretical estimate of air flow data is carried out by applying Boussinesq's hydrostatic model. Research of an impact of rustication joints interval on air flow data via physical simulation is performed for different façade configurations. Based on the results obtained, the most optimal solution is the design of a ventilated facade without rustication joints, or with the largest joints interval value. 10.18720/MCE.73.4 ventilated faсade enclosing structure heat-gravitational motion average velocity ventilated air gap energy efficiency https://engstroy.spbstu.ru/article/2017.73.4/

RAR RUS 49-61 State enterprise "NIPTIS Housing Institute named after Ataev S.S." Danilevski Leonid leonik@tut.by State enterprise "NIPTIS Housing Institute named after Ataev S.S." Danilevsky Sergey niptis-7@tut.by The algorithm and accuracy of definition of heattechnical indicators of buildings The object of the given research is the thermotechnical characteristics of buildings. The problem of thermotechnical indicators measurement arises at the acceptance of the buildings in use and also while performing work on energy classification of buildings in use. The two-level procedure of specific consumption definition of thermal energy for heating is offered: the coefficient of heat losses of the building is defined, and then the specific consumption of thermal energy for heating for settlement conditions is estimated. The given article suggests the optimal algorithm of the coefficient of heat losses determination according to the consumption of thermal energy for the buildings, not depending from the outdoor air temperature and the power of household thermal emissions of the building. There are also the results of the estimation of the coefficient of the coefficient of heat losses and specific consumption of thermal energy for heating for the conditions estimation according to the long-term observation for highrise buildings. There are also the estimation of the RMS error of determining the coefficient of the coefficient of heat losses and specific thermal energy consumption for heating for the conditions estimation, as well as the 75 % confidence interval for this indicator. The results can be used for the buildings in use energy classification. 10.18720/MCE.73.5 specific consumption of thermal energy on heating settlement service conditions measurements coefficient of specific heatlosses statistical characteristics classification of buildings https://engstroy.spbstu.ru/article/2017.73.5/

RAR RUS 62-69 0000-0003-2533-9732 National Research Moscow State Civil Engineering University Samarin Oleg samarin-oleg@mail.ru The probabilistic-statistical modeling of the external climate in the cooling period Currently, the successful development of construction industry depends on the improved energy performance of buildings, structures and facilities, as well on the quality estimation of the outdoor climate. The problem of feasibly more accurate determination of energy consumption by climatic systems in buildings is a very high-priority task now because of decrease of energy and fuel sources and because of actualization of building standards in many countries. That is why it is very important to find simple but enough accurate dependences between climatic parameters in the heating as well as in the cooling seasons of a year. In the paper the modern principles accepted in different countries for the selection of the design climate information for the design of building envelopes and systems to ensure building microclimate are considered. Main shortcomings of the methods, including the concept of "typical year", are shown and the advantages of generating climate data arrays programmatically with the use of a pseudorandom number generator are described. Some results of the calculation of current temperature of the external air during the warm period of the year with different safety are presented using numerical modeling with Monte-Carlo procedure. The possibility of practical implementation of probabilisticstatistical principle of climatic data for some calculations relating to climatic systems and thermal regime of the building are shown. The comparison of the obtained values with the analytical expression for the normal distribution of random variables is presented and relationships for the selection of its main parameters according to the existing climatic manuals are proposed. 10.18720/MCE.73.6 probabilistic-statistical model climate typical year safety index Monte-Carlo procedure temperature the cooling period https://engstroy.spbstu.ru/article/2017.73.6/

RAR RUS 70-87 57196066346 0000-0002-8051-5914 National Research Moscow State Civil Engineering University Denisov Aleksandr den-al-v@inbox.ru

Moscow, Russia

The impact of superplasticizers on the radiation changes in Portland cement stone and concretes The authors have estimated the effect of advanced superplasticizers of types Muraplast, Reamin, Weiss SM, Polyplast SP-1 and Melflux on radiation changes in Portland cement stone and concretes of radiation protection, based on experimental data from available literature, about the effect of such superplasticizers on thermal changes of Portland cement stone and the known analogy between thermal and radiation changes in Portland cement stone exposed to neutrons. The estimate of radiation changes in volume and compression strength of Portland cement stone used proposed ratios between the effect of superplasticizers on thermal and radiation changes in Portland cement stone, obtained through processing the published experimental results about the effect of superplasticizers S-3 and S-4 on radiation and thermal changes in Portland cement stone. Radiation changes in volume, crack formation, compression strength and deformation modulus of concretes, were measured with developed and tested methods for analysis of radiation changes in concretes based on information on changes of their components (aggregates and Portland cement stone). It has been established that advanced superplasticizers generally diminish radiation changes in Portland cement stone and concretes. The authors have demonstrated the extent by which such changes are reduced depending on various factors. It has been found that the effect of superplasticizers is in inverse proportion to the water-to-cement ratio of the mix as cement stone is made, by increasing the content of superplasticizer in the mix (for water reducing), and it depends on the fluency of fast neutrons. 10.18720/MCE.73.7 superplasticizers Portland cement stone concretes civil engineering radiation changes in volume strength and deformation modulus effect of neutron radiation from nuclear reactors https://engstroy.spbstu.ru/article/2017.73.7/

RAR RUS 88-95 Technical University in Košice Al Ali Mohamad mohamad.alali@tuke.sk Bajzecerova Viktoria viktoria.bajzecerova@tuke.sk Technical University in Košice Kvocak Vincent vincent.kvocak@tuke.sk Design methods of timber-concrete composite ceiling structure Timber-concrete composite structural members are increasingly used in the case of restoration of wooden ceilings. In the other hand, their use also increases in the case of new buildings. Design methods of the composite structures have been evolving since their first use. This expressive evolution of design methods is related to extensive research in this area in last three decades. This paper presents basic information about realisation, experimental and numerical analysis of timber-concrete composite ceiling with nail connections. The design of the mentioned ceiling was realised according to the relevant standards and recommendations in that time. The paper also presents a comparison between the design results of this composite ceiling and deflections measured during experimental short term loading process with the currently widely used analytical calculation model, so called γ-method. This method takes into account the joint compliance of the used nails. In addition, creep behaviour of used materials and concrete shrinkage were implemented in this calculation model. Comparison of the numerical and experimental results shows, that the current method better reflects the real stiffness of the ceiling structure. On the base of mentioned calculation model, the final deformation of the ceiling was also predicted. 10.18720/MCE.73.8 timber-concrete сomposite structures Design methods γ-method https://engstroy.spbstu.ru/article/2017.73.8/

RAR RUS 96-112 6506150284 0000-0003-1139-3164 Moscow State University of Civil Engineering (National Research University) Sainov Mikhail mp_sainov@mail.ru

Moscow, Russia

National Research Moscow State Civil Engineering University Lubyanov Vladislav lubyanovvv@yandex.ru Stress-strain state of seepage-control walls in foundations of embankment dams Results are considered of systematic study of stress-strain state (SSS) of a seepagecontrol wall arranged in the embankment dam foundation. The following factors affecting the wall SSS were studied: the wall depth, deformation modulus of the wall material, the pattern of the wall resting. Studies were conducted with the aid of numerical modeling. They revealed significant role of friction processes and slippage at the contact with soil on the wall SSS formation. It is friction through which soil transfers to the wall the compressive longitudinal forces which increase while the wall stiffness increases. It was also revealed that conditions of operation of suspended walls are more favorable that those of walls resting on rock. Empirical formulae were proposed which permit predicting the value of maximum compressive forces in the wall. Compressive strength of the wall was assessed. At that, it was taken into account that strength of plastic clay-cement concrete considerably increases if it is compressed from all sides as compared to uniaxial compression. A considerable role of accounting this effect was shown at selecting material for arrangement of the wall. It was obtained that to provide the wall strength it is necessary to have its material deformability exceeding the deformability of the surrounding soil not more than 5 fold. It was revealed that at perceiving by the wall the horizontal forces of seepage or hydrostatic pressure the longitudinal forces in it sharply decrease. It was obtained that then there is a danger of the wall tensile stress failure, because bend deformations in the wall cause irregular distribution of stresses in it. Especially it is hazardous for the walls made of rigid materials. 10.18720/MCE.73.9 cut-of wall stress-strain state clay-cement concrete numerical modeling strength https://engstroy.spbstu.ru/article/2017.73.9/