75504 2712-8172 4 120 2023 1-148

RAR RUS 12001-12001 36787104800 0000-0002-9440-0341 National Research Moscow State Civil Engineering University Kozlov Dmitry kozlovdv@mail.ru

26 Yaroslavskoye av., Moscow, 129337 Russia

0000-0002-0586-9464 Moscow State University of Civil Engineering (National Research University) Dzhumagulova Nazira dnazira@rambler.ru

Moscow, Russian Federation

Engineering hydrology technologies to reduce threats from ice phenomena Introduction. The floods caused by ice phenomena are among the "three leaders" of dangerous hydrological phenomena that damage the economy and the environment in Russia. Methods. The methodological basis of the study was: passive experiment, analysis and synthesis, generalizations, methods of mathematical modeling of hydrological and hydraulic processes, multivariate analysis and expert assessments. Results and Discussion. Generalization, analysis and systematization of knowledge about the processes of formation of ice difficulties were carried out. It is shown that under the conditions of climate change and ice regime of water bodies as a result of human economic activity, the methods of forecasting ice phenomena are being transformed, which are mainly based on statistical dependencies established according to the hydrometeorological observations. An updated zoning of the territory of Russia by the genesis of the ice phenomena and types of dangerous hydrological phenomena with recorded material damage is presented. The views on modern methods of monitoring dangerous ice phenomena and the use of its results for timely forecasting, adoption of rules for the use of water resources and preventive measures are expounded, while the consequences of the impact of these phenomena on water bodies are assessed. The modern trends in the development of mathematical modeling of the processes of formation of ice hanging dams and ice jams, the transporting ability of subglacial flows in combination with models of river flow formation and functioning of water management systems are revealed. The prospects for research aimed at developing measures to counter threats to water safety caused by dangerous ice phenomena are determined. Conclusion. The results of qualitative and quantitative analysis can be used to collect information on the consequences of exposure and monitoring of ice hazards. Trends in the development of mathematical modeling of the processes of congestion and anchor ice dam formation, transporting ability of subglacial flows in sections of rivers with engineering structures are associated with a combination of hydrodynamic models, models of river flow formation and the functioning of water management systems. The prospects for research aimed at developing measures to counter threats to water safety caused by dangerous ice phenomena were determined. 10.34910/MCE.120.1 627.81:556.5 water safety water body river dangerous hydrological phenomenon (process) iced phenomenon (process) ice regime ice-сlogging modeling monitoring https://engstroy.spbstu.ru/article/2023.120.1/

RAR RUS 12002-12002 0000-0002-1183-6407 National Institute of Technology Bhardwaj Avinash avinash@nith.ac.in

Hamirpur, India

0000-0003-0031-642X National Institute of Technology Sharma Ravi Kumar ravi@nith.ac.in

Hamirpur, India

Influence of industrial wastes and lime on strength characteristics of clayey soil The stress-strain and volumetric behavior, shear strength parameters, permeability and stiffness of soft clayey soil stabilised with various proportions of molasses, waste foundry sand, and lime are investigated in this article using the variable head permeability test and consolidated drained triaxial test. The results of the tests showed that the permeability, stress-strain and volumetric behavior of the soft clayey soil were significantly enhanced by the addition of molasses, waste foundry sand, and lime. At all confining pressures, the volumetric strain was found to decrease with the inclusion of additives. The additives to soft clayey soil reduced cohesion to a limited extent whereas significantly increasing the angle of shearing resistance. Furthermore, scanning electron microscope (SEM) images of all the optimum composites demonstrate that with the additives, a composite with higher strength and density is observed, and the geotechnical properties of soft clayey soil are improved, thereby making it suitable as a subgrade material in pavement construction. 10.34910/MCE.120.2 624.15 soil stabilization additives binders stress-strain curves scanning electron microscopy environmental Impact recycling https://engstroy.spbstu.ru/article/2023.120.2/

RAR RUS 12003-12003 57170472500 0000-0002-1027-1811 Volgograd State Agricultural University Klochkov Yury Klotchkov@bk.ru

Volgograd, Russia

57189646401 0000-0001-9148-2815 Volgograd State Technical University Pshenichkina Valeria vap_hm@list.ru

Volgograd, Russian Federation

7202396806 0000-0002-7098-5998 Volgograd State Agricultural University Nikolaev Anatoliy anpetr40@yandex.ru

Volgograd, Russia

55235780600 0000-0001-9234-7287 Volgograd State Agricultural University Vakhnina Olga ovahnina@bk.ru

Volgograd, Russia

57215535887 Lomonosov Moscow State University Klochkov Michael m.klo4koff@yandex.ru

Moscow, Russia

Stress-strain state of elastic shell based on mixed finite element In a mixed formulation, a four-node finite element was developed, which is a fragment of the middle surface of the elastic shell. Longitudinal forces and bending moments, as well as displacements and their first derivatives with respect to curvilinear coordinates, were taken as nodal unknowns. To obtain the compliance matrix, the Reissner functional was used, in which the stresses, when using the direct normal hypothesis, are represented by dependences on the forces and bending moments of the middle surface, the approximation of which was carried out by bilinear functions. In the interpolating expressions for the kinematic sought quantities, Hermite polynomials of the third degree were used. As a result of minimizing the transformed functional with respect to the force and kinematic nodal unknowns, the compliance matrix of the accepted discrete element was formed. Verification of the developed discrete element in a mixed formulation was carried out on the examples of calculations of cylindrical shells with circular and elliptical cross sections. The values of the force parameters found using the developed algorithm adequately satisfied the conditions of static equilibrium (the calculation error was less than 0.5 %). An analysis of the obtained finite element solutions showed the effectiveness of the developed algorithm and made it possible to note the possibility of its use in calculations of thin-walled structures made of incompressible materials. 10.34910/MCE.120.3 539.3 thin-walled shell-type structure modified mixed functional compliance matrix four-node sampling element force and kinematic unknowns https://engstroy.spbstu.ru/article/2023.120.3/

RAR RUS 12004-12004 57226389898 0000-0002-2471-4062 Department of State Expertise; Northern (Arctic) Federal University named after M.V. Lomonosov Chernova Tatyana zhuravleva.t.pav@mail.ru

Arkhangelsk, Russian Federation

36884074300 0000-0002-2583-3012 Northern (Arctic) Federal University named after M.V. Lomonosov Melekhov Vladimir v.melekhov@narfu.ru

Arkhangelsk, Russia

Behavior of timber-timber composite structure connected by inclined screws The behavior of timber composite structure made of cross laminated timber (CLT) panel and glued laminated timber (GLT) beam was considered in this paper. Bending tests of a CLT-GLT composite structures with and without fasteners were conducted. CLT panel and GLT beam were connected by screws installed at a 45° angle to the GLT axis grain. It was experimentally proved that the application of inclined screws increases the strength of the CLT-GLT composite structure by 1.3 and 1.6 times, stiffness – by 1.6 and 2.1 times, shear capacity – by 2.1 and 3.5 times for two orientation types of CLT panel (CI and CII), respectively. Two types of CLT panel orientations were considered: with the top layer oriented parallel to the GLT axis (CI) and oriented perpendicular to the GLT axis (CII). The CLT-GLT composite structure with the top layer oriented parallel to the axis of the GLT beam has 50 % more strength and 14 % more stiffness than a composite structure with the top layer oriented perpendicular to the GLT axis. Based on numerical and experimental results, a design procedure was suggested to determine the strength and strain characteristics of the CLT-GLT composite structure connected by inclined screws. 10.34910/MCE.120.4 692.526 stress-strain state cross laminated timber (CLT) glulam (GLT) bending tests timber-timber composite (TTC) dowels inclined screws strength stiffness finite element method numerical model https://engstroy.spbstu.ru/article/2023.120.4/

RAR RUS 12005-12005 Peter the Great Saint Petersburg Polytechnic University Sabri Mohanad Muaya mohanad.m.sabri@gmail.com

Polytechnicheskay, 29

6507787139 OOO “PI Georekonstruktsiya” Shashkin Konstantin cshashkin@yandex.ru Soil-structure interaction: theoretical research, in-situ observations, and practical applications This research paper presents a comprehensive investigation on soil-structure interaction, combining theoretical research and in-situ observations. Detailed calculations and a thorough comparison of the results with long-term settlement observations are provided, accompanied by the validation of the proposed elasto-visco-plastic soil model through rigorous calculations. Real-world examples showcasing the application of design methods incorporating soil-structure interaction calculations in civil and industrial engineering, as well as in the reinforcement and restoration of historical buildings, are also presented. The study reveals that neglecting the spatial behavior of soil leads to significant underestimation of stresses in structures. For buildings on spread footings, the underestimation can range from 150% to 400%, while for buildings on pile foundations, it can be as high as 200% to 900%. Furthermore, an innovative architectural solution employed in a high-rise building successfully mitigated settlement issues by utilizing longer piles. The calculated settlement was reduced to 60 mm, and the actual settlement observed three years after construction was only 32 mm, indicating the effectiveness of the implemented solution. By emphasizing the importance of soil-structure interaction calculations, this research fosters a unified approach among various stakeholders involved in construction design. The findings and methodologies presented in this paper hold great potential to significantly enhance the field of geotechnical engineering, enabling more accurate and effective design approaches for various structures and applications. 10.34910/MCE.120.5 624.1 soil-structure interaction design methods structural response seismic response elasto-visco-plastic model soil model long-term settlement restoration historical buildings finite element method non-linear analysis https://engstroy.spbstu.ru/article/2023.120.5/

RAR RUS 12006-12006 Perm National Research Polytechnic University; Perm State Agro-Technological University named after academician D.N. Prianishnikov Tretiakova Olga olga_wsw@mail.ru

Perm, Russia

Prismatic face slope piles operating under frost heaving The effectiveness of piles with reverse surface slope in frost heaving of soil has been the subject of discussion in many papers. In the previous works, the author considered cylindrical piles with an upper reverse taper and calculation method for the piles under these conditions. However, in order to extend the area of their use it is necessary to consider other configurations of piles as well. In this study, prismatic face slope piles are modeled for soil frost heaving conditions; equilibrium equations for calculating prismatic piles with four, six and eight faces are derived. The equilibrium equation for prismatic face slope piles in general form is also given. The equations make it possible to determine geometric parameters of piles ensuring their stability in soil under the action of tangential frost heaving forces. The author analyzes material capacity of cylindrical taper piles and prismatic face slope piles. The piles have the same bearing capacity in thawed soil and operate under the same geological and climatic conditions set before. The square pile with a sloping face shows the lowest material capacity. The proposed approach can be used for prismatic piles with a different number of faces in various conditions. 10.34910/MCE.120.6 624.154:624.139.32:519.87 frost heaving prismatic face slope pile equilibrium equation stability https://engstroy.spbstu.ru/article/2023.120.6/

RAR RUS 12007-12007 Kazan State University of Architecture and Engineering Vdovin Yevgeniy vdovin007@mail.ru https://orcid.org/0000-0001-9680-6698 Kazan State University of Architecture and Engineering Stroganov Victor svf08@mail.ru

Kazan, Russia

Phase structure of cement pastes with antifreeze agents This paper is concerned with changes in the phase structure of cement paste modified by complex antifreeze agents based on sodium formate, calcium chloride and S-3 superplasticizer. Complex modifiers were developed for cement-crushed mixtures hardening at low temperatures (down to –15.0 °C) used in pavement structures. In countries where construction and operation of highways occur at low air temperatures (below 0 °C), it is promising to use the method of modifying cement-crushed mixtures with complex antifreeze agents. The structural studies of cement paste with these additives are poorly described in scientific literature. Therefore, the aim of this work was to consider the impact of complex antifreeze agents in cement paste on the peculiarities of phase structure formation and the relationship between the structure and the properties of the obtained materials. The cement paste was tested for compressive strength using the standard technique; then after preparation, the samples were tested by X-ray, differential thermal and thermogravimetric analyses. It was established that the modification provides the possibility to increase the content of the crystalline phase compared with the amorphous one in the form of new formations (portlandite and dicalcium hydrosilicates). The developed complex modifiers contribute to activation of hydration processes in cement paste, which is confirmed by the level of the hydration degree up to 0.6 and the integral value of weight loss up to 20.5 %. The relationships between the increase in the compressive strength of cement paste and the increase in the hydration degree of calcium silicates and the integral value of weight loss were established. It was shown that the combined use of components of the complex three-component additive provided synergism of processes of structure formation and, as a consequence, an increase in the strength of cement paste. The use of the developed compositions of antifreeze agents in the technology of construction of cement-crushed bases at subzero temperatures (up to –15 °C) prolongs the road construction season and improves the operational indicators of road pavement materials. 10.34910/MCE.120.7 691.3 phase structure cement paste antifreeze agents X-ray phase analysis differential thermal and thermogravimetric analysis electron microscopy cement-crushed stone mixtures https://engstroy.spbstu.ru/article/2023.120.7/

RAR RUS 12008-12008 6602848417 0000-0002-0587-4722 National Research Moscow State Civil Engineering University Kantardgi Izmail kantardgi@yandex.ru 6603383591 0000-0002-5010-6239 Shirshov Institute of Oceanology, Russian Academy of Sciences, Leont'yev Igor igor.leontiev@gmail.com

Moscow, Russian Federation

57222865129 0000-0002-4186-2753 Moscow State University of Civil Engineering (National Research University) Kuprin Alexander rtyter55@gmail.com

Moscow, Russian Federation

Sedimentation simulation of the Temryuk seaport approach channel The sedimentation of the approach channel and the water area of Temryuk port is an important problem that has recently attracted the attention of researchers and engineers. The object of the study is the influence of the extension of the east and west breakwaters of the port. An analytical method of forecasting lithodynamic processes for various extensions of protective breakwaters was used. To verify the results, an analysis of space images of the coastal zone was applied. The volumes of sedimentation of the sea part of the Temryuk port approach channel were determined; recommendations for the extension of breakwaters were given. The sedimentary layer in the Temryuk Bay has two demarcated zones, one dominated by silty material, and the other, coastal, by fine-grained sand. Therefore, to determine the total alongshore sediment flow, the movement of muddy and sand flows was determined separately. The west breakwater retains only a small part of the sand transported to the canal; the east breakwater also has an insufficient length. The majority of the sand passing in the west and east directions falls into the canal. After the extension of the east breakwater by 100 m, the sedimentation of sand will be due mainly to its arrival from the west side, and thus the maximum thickness of the sediment layer will be about 2 m. The extension of the east breakwater by 200 m does not lead to a significant improvement compared to the extension option of 100 m, therefore, to reduce the sedimentation, it is necessary to extend the west breakwater by 100 m as well. After the extension of the west breakwater, the flow of sand into the channel from the west side will be significantly reduced. Thus, after the lengthening of both breakwaters, the volume of sedimentation of the channel with sand will decrease from 55 to 15 thousand cubic meters per year. The main contribution to the sedimentation will continue to be made not by sandy, but by silty material. 10.34910/MCE.120.8 627.52 longshore sediment transport erosion drift accumulation protective measures mathematical model https://engstroy.spbstu.ru/article/2023.120.8/

RAR RUS 12009-12009 0000-0002-8898-4766 Tomsk State University of Architecture and Building Churilin Vladimir lex-16-2008@mail.ru

Tomsk, Russian Federation

Tomsk State University of Architecture and Building Matvienko Oleg matvolegv@mail.ru

Tomsk, Russian Federation

Tomsk State University of Architecture and Building Efimenko Vladimir svefimenko80@gmail.com

Tomsk, Russian Federation

Tomsk State University of Architecture and Building Efimenko Sergei svefimenko_80@mail.ru

Tomsk, Russian Federation

Regression models of irregular vertical displacement of a roadway cross section caused by frost heaving Subgrade clay is subjected to frost heaving under the effect of cold air and adequate soil moisture. The existing prediction models for frost heaving have a number of drawbacks: they are complicated for practical use and unable to evaluate irregular vertical displacements. Winter monitoring of 14 road sections was performed to evaluate irregular vertical displacement of pavement surface cross section under the action of frost heaving. The obtained data on vertical displacement of points were processed using mathematical statistics methods, and predictive regression models were built for vertical displacement of pavement during winter season. Stable relations were defined between displacement of points on the broken line (center-line of a road) and the factors including air-freezing index, thermal resistance of pavement, impact of subsurface water on frost heave, the pressure of pavement on the subgrade surface. Adequacy of the built models was checked using the results of displacement of points on the pavement surface within test sections. The first check concerned comparison of the values of modeling of the average displacement of points on the broken line caused by frost heaving, where mean absolute error was up to 20 %. For the case of close occurrence of subsurface water, the model prediction of the average displacement of points on the broken line showed significant difference from the actually recorded values. The second check concerned the displacement of points on the pavement in relation to displacement of points on the broken line, with the mean absolute value of up to 13 %. 10.34910/MCE.120.9 624.139.22 frost heaving air-freezing thermal resistance of pavement pavement displacement Regression model https://engstroy.spbstu.ru/article/2023.120.9/

RAR RUS 12010-12010 Tashkent Institute of Irrigation and Agricultural Mechanization Engineers Khodzhaev Dadakhan khodzhaevda@mail.ru 6506522453 0000-0001-8114-1187 Tashkent Financial Institute Abdikarimov Rustamkhan rabdikarimov@mail.ru

60A, A.Temur street, Tashkent city, 100000

0000-0001-9340-4474 McGill University Amabili Marco marco.amabili@mcgill.ca

Montreal, Canada

Tashkent Institute of Irrigation and Agricultural Mechanization Engineers Normuminov Bakhodir bnormuminov1977@mail.ru Parametric oscillations of a viscous-elastic orthotropic shell of variable thickness A solution to the problem of parametric oscillations of a viscous-elastic orthotropic shallow shell of variable thickness is presented. Dynamic loading acts along one side of the shell in the form of a periodic load. Unlike linear problems, the nonlinear problem under consideration could not be solved by applying analytical methods; therefore, approximate methods were used. The mathematical model of the problem is built within the Kirchhoff-Love theory. In this case, tangential inertial forces and geometric non-linearity are taken into account. Deflection and displacements approximation is performed using the Galerkin method in higher order approximations, which allows reducing the problem solution to a system of nonlinear integro-differential equations (IDE) with variable coefficients. The weakly singular Koltunov-Rzhanitsyn kernel with three rheological parameters is used as the relaxation kernel; it describes the viscous-elastic properties of the shallow shell. A numerical method based on the use of quadrature formulas is used to obtain a resolving system of equations for the problem. To obtain numerical results, a computer software was compiled in the Delphi environment for a computational algorithm of the problem solution. The effects of viscous-elastic, orthotropic, nonlinear properties of the shell material, thickness variability, and other physical, mechanical, and geometrical parameters on the dynamic strength of a shallow shell are studied. 10.34910/MCE.120.10 539.3 thin walled shell viscoelasticity composite materials variable thickness nonlinear vibrations dynamic stability Galerkin method numerical method https://engstroy.spbstu.ru/article/2023.120.10/