33407 2304-6295 3 112 2024 1-60

RAR RUS 11201-11201 AAE-3259-2020 56296687300 0000-0002-2299-3096 Peter the Great St. Petersburg Polytechnic University Rybakov Vladimir Alexandrovich fishermanoff@mail.ru

St. Petersburg, Russian Federation

0000-0002-2993-6836 Tsvetkova Anna Andreevna annatsvetkova2014@mail.ru Stiffness of vertical keyed joints of large panel buildings before cracking The object of the research is the linear stiffnesses of vertical keyed joints of wall panels of multi-story buildings before the moment of cracking. This work aims to propose and substantiate methodology for calculating the linear stiffnesses of two-node special finite elements used for modeling vertical joints in calculation software. Methods. To obtain the axial stiffness it is proposed to consider the properties of the joint concrete, the geometry of the joint and the parameters of the finite element calculation scheme of the building using Hooke's law. To obtain the relation for calculating the shear stiffness in the plane of the panels, when considering keys, the joint is considered as a set of elements, that are connected in series and in parallel, which stiffness is calculated accordingly. To obtain the dependence for calculation the shear stiffness in and out of the plane of the panels, without considering keys, the relations of the theory of elasticity are used. Results. A method for calculating the stiffnesses of vertical key joints of large-panel buildings in the three orthogonal directions before the moment of cracking is proposed and substantiated, the expediency of considering the work of shear in the joint when calculating its stiffness is shown. It is substantiated, that there is only slight influence of the geometry of keys on the results of calculating the stiffnesses in the linear stage of the work of the joint. The scope of application of the proposed methodology is determined. The comparison between the calculation results of a 5-storey large-panel building from a 9-point seismic impact with setting the stiffnesses of two-node finite elements according to the proposed methodology and according to the methodology currently used in design practice is carried out. The influence of reinforcement in the vertical joint on the results of calculating its stiffnesses before the moment of cracking is estimated. 10.4123/CUBS.112.1 69 Large-panel building Joint stiffness Linear stage Two-node special element https://unistroy.spbstu.ru/article/2024.112.1/ 11201.pdf

RAR RUS 11202-11202 0000-0002-6155-060X Peter the Great St.Petersburg Polytechnic University Shabunina Daria Evgenievna shabunina_de@spbstu.ru

St.Petersburg, Russian Federation

Kudryavtsev Vadim Sergeevich kudriavtcevvadim00@gmail.com 0000-0002-2410-5216 Chizhikov Vladimir Petrovich vovach1952@gmail.com Passenger speeds as a function of human traffic density in peak hours of subway operation The object of research is the movement of passengers at the subway station in peak hours. The work aims to obtain dependence of passenger speeds of different mobility groups on the human traffic density on a horizontal site, on the down staircase and on the up staircase in peak hours of subway operation. Method. To obtain the dependences of passenger speeds, experimental studies were conducted on observations of passenger traffic at loaded stations of St. Petersburg subway during the peak hours of station. The experimental data were processed using the least squares method (second-order polynomial model). Results. Mathematical dependences of passenger movement speeds of mobility groups M0-3, M2 and M3 on human traffic density were obtained. It was established that the dependences of passenger speeds on density given in the Order of the Ministry of Emergency Situations of Russia No. 1140 (allowed to be used for calculation of the operational regime of the subway) are overestimated on average by 75% on the horizontal site, by 20% on the downward stairway, by 40% on the upward stairway in comparison with the experimental speeds due to consideration of another type of traffic (evacuation) and not considering the features of the subway operation. The obtained dependences can be used as input data in the development of simulation model of passenger traffic in the assessment of space-planning solutions of the subway. 10.4123/CUBS.112.2 69 Subway Passenger movement Experimental study Density of human traffic Mobility group of passengers https://unistroy.spbstu.ru/article/2024.112.2/ 11202.pdf

RAR RUS 11203-11203 B-4397-2014 56826013600 0000-0003-1071-427X Peter the Great St. Petersburg Polytechnic University Gravit Marina Viktorovna marina.gravit@mail.ru

St. Petersburg, Russian Federation

0000-0003-4394-0791 Institute of Computational Modelling of the Siberian Branch of the RAS Kirik Ekaterina Sergeevna kirik@icm.krasn.ru

Krasnoyarsk, Russian Federation

Kozupitsa Ivan Sergeevich kozupitsa.is@edu.spbstu.ru Solntseva Yaroslava Yurievna solntseva.yayu@edu.spbstu.ru Fire safety in malls: Curtains for fire hazards localization and safe evacuation With the development of countries, the purchasing capacity rises, therefore the number of shopping malls increases. Shopping malls have intricate layouts with large retail and atrium area. Moreover, a lot of violations in terms of fire safety may be committed. These factors increase the risk of fire danger in the building of the shopping center. The object of research is a typical three-story shopping center. The article evaluates the involvement of a fire curtain, in the form of a roller curtain, in ensuring fire safety during evacuation. Method. The "Sigma PB" software package was used to create a computer model of the shopping center and simulate the spread of fire and evacuation. Five scenarios were generated, and the spread of fire hazard factors and evacuation under fire conditions were simulated. Results. Based on the modeling, it was concluded that the absence of a fire curtain does not contribute to limiting the spread of fire hazard factors and does not worsen the condition of evacuation routes in the considered scenarios. The use of the fire curtain EI60 is inappropriate. 10.4123/CUBS.112.3 69 Multifunctional Building Fire safety Fire hazards Evacuation time Organizing evacuation Fire curtains https://unistroy.spbstu.ru/article/2024.112.3/ 11203.pdf

RAR RUS 11204-11204 Kudryavtsev Vadim Sergeevich kudriavtcevvadim00@gmail.com R-6085-2016 57196054199 0000-0002-0840-6828 Peter the Great St. Petersburg Polytechnic University Radaev Anton Evgenevich TW-inc@yandex.ru

St. Petersburg, Russian Federation

B-4397-2014 56826013600 0000-0003-1071-427X Peter the Great St. Petersburg Polytechnic University Gravit Marina Viktorovna marina.gravit@mail.ru

St. Petersburg, Russian Federation

Interpolation between engineering-geological wells with consideration of the genetic type of the element The object of research is the internal boundaries of engineering-geological elements (EGE). This work aims to develop a procedure for interpolation of engineering-geological survey results between wells. Methods. The procedure for interpolation of engineering-geological survey results for designing internal boundaries of engineering-geological elements, based on the application of the modified Laplace equation, namely the approximate solution using a discrete problem for a plane coordinate system. Results. The procedure of interpolation of engineering-geological survey results between wells was developed. The mathematical dependence is obtained from the equation of Laplace for a discrete task in a plane coordinate system with the introduction of additional coefficients that allow to consider the character of change of internal boundaries. The best result was achieved at calculation taking into account the coefficient influencing the distance of points from the calculated point, weight coefficient of intermediate points and setting the number of distant points. It was found that the best result was achieved by increasing the number of calculation iterations. Conclusion. The combination of specified parameters (number of neighboring points, weight coefficient of intermediate points and the coefficient influencing the distance of points from the calculated point) allows to obtain profiles of internal boundaries of engineering-geological elements of different genesis and lithography. The developed procedure of interpolation can be applied for construction of engineering-geological sections, engineering-geological models and geotechnical models. 10.4123/CUBS.112.4 69 Engineering geology Internal boundaries of elements Automated construction Interpolation Genetic type of element https://unistroy.spbstu.ru/article/2024.112.4/ 11204.pdf

RAR RUS 11205-11205 Storozhev Sergei Alexeyevich sstorozhev4@mvd.ru 0000-0002-7422-5494 Peter the Great St.Petersburg Polytechnic University Vafaeva Khristina Maksudovna vafaeva_hm@spbstu.ru

Saint Petersburg, Russian Federation

Crash modeling of bridge railings: Impact of post spacing on performance The object of research is a barrier side one-way bridge railing with a height of 1.1 meters and a rack spacing of 2 meters. The purpose of this work is to analyze the effectiveness of the finite element method (FEM) in modeling the collision between a bus and the bridge railing, and to determine the impact of rack spacing on the railing's performance characteristics, such as dynamic deflection and working width. Method. The FEM is employed to simulate the collision dynamics between the bus and the bridge railing. The railing model consists of several key components: bridge post, upper rail, console-absorber, and lower beam section, all modeled using 2D shell elements. The bus model includes detailed geometric and material properties, validated through simulations to ensure accurate replication of real-world conditions. Simulation parameters – such as initial speed, angle of impact, and the material properties of the bus and railing components – are based on experimental data. The quality of the model is assessed using criteria including trajectory deviation, suspension displacement, and acceleration at the vehicle's center of mass. Results. The comparison of simulation results with full-scale tests confirms the validity of the FEM model. Key findings include the stability of the bus trajectory without overturning or railing overrun, and the effective containment capacity of the railing, capable of withstanding a kinetic energy impact of 406.34 kJ. The study identifies the optimal rack spacing for balancing metal consumption and dynamic deflection, which ranges between 1.5 meters and 2 meters. The results indicate a significant correlation between rack spacing and the railing's performance characteristics, with detailed comparisons of dynamic deflection and working width for various spacings. The calculated dynamic deflection and residual deformation values closely match experimental results, affirming the reliability of the FEM approach in modeling these complex interactions. 10.4123/CUBS.112.5 69 Finite element method (FEM) Explicit dynamics Bridge barriers Post spacing Dynamic deflection Computational modeling Road safety Metal efficiency Impact analysis Bridge railing design https://unistroy.spbstu.ru/article/2024.112.5/ 11205.pdf

RAR RUS 11206-11206 N-6730-2017 57199850188 0000-0002-2279-1240 Far Eastern Federal University Fediuk Roman Sergeevich roman44@yandex.ru

Vladivostok, Russian Federation

Berdnikov Alexey Anatolievich Shilonosov Artem Vladimirovich Panarin Igor Ivanovich Fediuk German Romanovich Injection mortars for road pavement subgrade fixing The object of research is a range of injection mortars (IM) based on composite binders, crushed to Ssp = 500 m2/kg, obtained using CEM I 42.5 N, partially replaced by technogenic resources with the addition of superplasticizer Polyplast PFK-NLM. The purpose of this work is development and comprehensive research of injection mortars for road pavement bases. The tasks for achieving the set purpose are designing the composition of IMs, studying their fresh and physical-mechanical properties, as well as the performances of the fixed bases. Method. The specific surface of bulk raw materials was studied using the PSH-11 device. Several characteristics were assessed for injection mortars: water-cement ratio, workability, water separation, mixture density, compressive strength, elastic modulus, frost resistance. Results. The viscosity of IMs indicates their high penetrating ability, since the flow time of the studied materials through the Marsh viscometer at water-to-binder ratio 0.62 and a water consumption of 140 l/m3 is 33-39 seconds. The start of setting is at least 75 minutes, which allows for effective fixing of road pavement bases. The composite binder contributes to a significant increase in the early compressive strength of IMs (up to 56% compared to the control composition) and flexural strength (up to 75%). The ratio of the flexural and compressive strength of the developed compositions (on 2nd day it is 0.13, on 7th - 0.11, and on the 28th - 0.12) often exceeds a similar characteristic of the control composition, despite the replacement of Portland cement by more than half by wt of wet magnetic separation (WMS) waste from ferruginous quartzites, technogenic fibrous materials (TFM) and SP, indicating the development of crack resistance of the material. An increase in the deformation characteristics of the mixture hardened on CB-50SP+1%TFM was established by 112% compared to the mixture on CEM I 42.5 N cement. Studies of the mixes deformation properties of the allow us to conclude that, based on the developed IMs and crushed stone from metamorphic shale, it is possible to obtain concrete for road pavement bases that meet the regulatory documentation for this type of construction. Tests of samples of reinforced crushed stone bases for the entire range of physical and mechanical properties and performances have shown that the developed IMs compositions allow, when strengthening crushed stone bases, to obtain concrete of class B5 - B10, and they can be used in the construction of pavement bases for high-quality roads. 10.4123/CUBS.112.6 69 Concrete Mortar Injection Road Strength Pavement Base Subgrade Fixing https://unistroy.spbstu.ru/article/2024.112.6/ 11206.pdf