Objective. The purpose of the research is modeling and analysis of technological processes occurring at the transshipment terminal of liquefied natural gas.

Method. The study is based on the methods of thermodynamic analysis, full-scale and computational modeling of processes and objects of refrigeration and cryogenic equipment in order to find optimal solutions in terms of efficiency, reliability and service life of low-temperature installations, machines and apparatus.

Result. The article describes the operation algorithm of an LNG transshipment terminal and proposes a mathematical apparatus for modeling the technological processes occurring in it. Information about the causes of the formation of LNG vapors (Boil-off gas (BOG)) during its transportation and reloading is presented, methods for utilizing excess LNG vapors are considered.

Conclusion. To maintain the cryogenic temperature of the unloading arms, an LNG recirculation line (recirculation pipelines) is provided.

Objective. The aim of the study is to develop the design of a thermoelectric system (TPS) for thermal action on the anterior segment of the human eyeball, as well as to conduct its field studies.

Method. The study is based on the methods of thermodynamic analysis, natural and computational modeling of processes and life support facilities.

Result. The design of TPP for thermal impact on the anterior segment of the human eyeball is presented. Its fullscale studies were carried out in accordance with the existing methods of thermophysical measurements. Curves of changes in the temperature of the surface of the gelatin model of the human eyeball over time during cooling and heating were obtained for the supply currents of the thermoelectric module (TEM) included in the TPP, equal to 2.5 A, 3 A, 3.5 A, A and 1 A, 1 .2 A, 1.4 A, as well as changes in the temperature of the object of influence over time when changing the cooling mode to heating and vice versa. To assess the possibilities of heat removal from the hot junctions of TEMs in the system, data were obtained on the change in their temperature over time during the cooling effect for various values of the module supply current.

Conclusion. It has been established that standard modules produced by domestic firms can be used as TEMs in the system. The duration of entering the TPP mode is about 230 s. The refore, it seems appropriate to bring the TPP to the operating mode before the actual procedures are carried out. It has been established that the duration of TPP switching from cooling to heating mode and vice versa is 230 s, which requires further optimization of the design and operating modes of the device through the use of more advanced types of TEMs and the use of forced operation of thermal modules in the transient mode.

Objective. The present article discusses the issue of modeling the duration of the refrigeration effect on a food product using the example of raw lean meat.

Method. The duration of the refrigeration effect consists of two stages: cooling and freezing. At the same time, the thermophysical characteristics of products are determined practically on a specialized experimental setup developed in the laboratory of the Department of Technological Equipment and Life Support Systems.

Result. Knowing the technological regimes, it is possible to determine the time spent on cooling and freezing various food products.

Conclusion. This technique can be applied in wide climatic conditions in the production of the Russian Federation on a large scale. If we increase the air speed at the surface of the product to 3 m/s, we will get a reduction in time by 502 s, provided R = 0.015 m and δ = 0.125 m. Having the initial and final conditions, you can quickly determine the duration of the refrigeration exposure, both for raw lean meat, and for any other food products, choosing the optimal one.

Objective. The aim of the study is to study the methods of temperature control using the Peltier element in a given temperature range.

Method. A heating method is applied using a Peltier element in a temperature control device of a small plate by regulating the current and using a cooling fan to reduce inertia.

Result. A technique for controlling the Peltier element to maintain the required temperature is obtained, which is carried out using the PWM method generated by the ATmega2560 processor. The H-bridge on the L6203 integrated circuit switches the current direction and can control the current up to 5A on the Peltier element using a PWM signal.

Conclusion. The resulting control algorithm provides an increase in the heating current on the Peltier until the temperature rises to a predetermined high temperature value, and then by changing the direction of the current, a cooling current is created on the Peltier element until the temperature of the copper plate drops to a predetermined low temperature. With repeated repetition of this sequence, the regularity of temperature changes is monitored to study the process of heating and cooling the plate using the Peltier element.

Objective. With the decreasing use of refrigerants with a high global warming potential, increasing the efficiency of refrigeration machines using natural working fluids is a very urgent task. The CO2 booster refrigerant cycle may be optimal for the fields of commercial refrigeration, climate engineering and heat pumps, but needs to be adapted to regions with hot climates. The purpose of the study is also to systematize possible ways to improve the spiral technology, as a guarantee of increasing the efficiency of booster refrigeration machines.

Method. Such solutions have already been tested by increasing the transcritical cycle efficiency through the use of an ejector and parallel compression. However, the use of a scroll compressor in the transcritical cycle may be a good alternative to these methods. This solution, a little bit improves technical and economic indexes of the refrigerating machine, in the most part reducing capital and operational costs. When considering the prospect of improving the efficiency of a booster system with scroll compressor, it is necessary to address the issue of compressor performance optimisation. An issue of this kind can be referred to improving the efficiency of the booster system, at the expense of the internal characteristics of the refrigeration machine.

Result. Thus, in this paper, a conceptual approach is considered to solve this problem based on a system analysis of the interconnection of the compressor as the main energy-intensive element of a refrigeration machine.

Conclusion. Development of conceptual model, allows to identify influence of various factors on scroll compressor operation and to build adequate mathematical model, to choose or develop necessary calculation methods.

Objective. Development of automated network attack detection systems capable of adapting to the ever-changing nature of network attacks and new types of threats. Such systems should be based on machine learning algorithms and models that are able to identify complex dependencies between data in the learning process.

Method. To train the models, a sample with signs of normal and abnormal traffic was prepared, and it was thinned and balanced as a result of preliminary statistical analysis. Five machine learning algorithms were selected and tested, both on a training set of features and on a real test set obtained experimentally. Based on the results of the experiments, a random forest classifier was selected, which showed the best results.

Result. A model for detecting network intrusions has been developed, which showed a detection accuracy of 0.99 on real traffic.

Conclusion. It is shown that a machine learning-based network intrusion detection system can solve the problem of flexible protection that could adapt to the ever-changing nature of network attacks, since one of the most important advantages of machine learning in detecting network intrusions is the ability to learn the signs of attacks and identify cases that are uncharacteristic of those that were observed earlier.

Objective. The purpose of the study is to develop a methodology for assessing the security of an automated control system of critical information infrastructure from DDoS attacks. The purpose of the methodology development is to provide the decision–maker with a scientifically sound tool for assessing the risk of implementing a DDoS attack.

Method. To achieve the stated goal of the study, simulation modeling based on the Monte Carlo method was used.

Result. The expediency of using Monte Carlo simulation to assess the probability of server failure under DDoS attacks is confirmed. It was concluded that the server can be considered as a queuing system, however, the flow of incoming applications under DDoS attacks is not Poisson, so the use of analytical expressions to assess the probability of failure is considered incorrect. The simulation results allow the decision-maker to assess the probability of server failure and make organizational and technical decisions to increase the level of security. Analysis of the simulation results showed the effectiveness of improving server performance by increasing service channels.

Conclusion. Thus, the developed methodology will be useful in conducting an information security audit of an organization to justify the amount of its insurance premium in the framework of cyber risk insurance. A possible direction for further research is to study the issue of computer network security, taking into account the features of a specific topology.

Objective. The aim of the study is to generalize the experience of using and reveal the features of methods for classifying and clustering images obtained by laser scanning.

Method. The study is based on the use of algorithms for recognition, clustering and classification of data obtained using laser scanning.

Result. A brief review of existing algorithms used for clustering images obtained by laser scanning has been carried out. The possibility of using sequentially the K-means and DBSCAN algorithms for clustering in relation to objects of various shapes is shown. The possibilities of using algorithms for the classification and clustering of laser reflection points (k-Means, DBSCAN, SVM) in the framework of solving territorial planning problems are analyzed.

Conclusion. The use of the presented algorithms makes it possible to form data arrays that, when superimposed on each other subsequently and further processed, make it possible to obtain even more accurate representations of objects and territories in territorial planning documents, and in the future, based on the use of machine learning methods and processing of data matrices available in memory, get more accurate information about objects on the ground.

Objective. The purpose of the study is to analyze the features of the functioning of protected automated systems and develop a structural diagram of a typical ATS AS, which includes various structural elements.

Method. As a fundamental method of conducting research is the method of system analysis.

Result. Based on the developed typical structural diagram of the ATS AS, threats to web servers were identified in accordance with the official website of the FSTEC, and, in accordance with them, potential vulnerabilities (weak points in terms of information security) were identified; a classification of all potentially dangerous threats to the information resource of protected ATS automated systems was developed and presented.

Conclusion. The materials of the article can be used to analyze and develop a methodology for quantitatively assessing the risks of information security violations of the web servers of the ATS of the Russian Federation; methods for assessing the level of security of the ATS of the Russian Federation; methods of access of regular users of the RF ATS AS to the information resource of these systems based on semantic analysis.

Objective. Development of principles for the construction of a multifunctional intelligent electric energy meter (MSE) with expanded communication and functional capabilities and the construction of MSE based on them for automated systems of commercial accounting of energy consumption (ASKUE).

Method. When developing the principles of the construction of the IEE, an analysis of existing electric energy metering devices was carried out and their main disadvantages were identified, which made it possible to improve the characteristics and expand the functionality of metering devices. The operability of the main components of the IEE is confirmed by the results of mathematical and physical modeling, which showed the possibility of improving the metrological characteristics and technical parameters that determine the quantitative, qualitative and cost characteristics of the devices.

Result. The principles of the construction of the IEE have been developed, which makes it possible to create IEE with expanded communication and functional capabilities for the ASUE.

Conclusion. Using them in ASCUE posvolit: -to build self-adjusting mesh networks based on them, which can be used in the construction of ASCS with increased survivability; -to ensure the exchange of accounting and service information with the ASKUE over the radio channel, PCL modem and RS-485 (CAN) interface, which increases the reliability of obtaining accounting information and integrate the MISEE into existing ASKUE, because it makes it possible to select the appropriate type of specific ASKUE interface or communication interfaces "counter-ASKUE";- regulate energy consumption and independent disconnection of the consumer from the network for each subscriber unit (separately for each subscriber) in case of arrears of payments, network overload and unauthorized access to the nodes and blocks of the meter in various ways;- to improve the operating conditions of the meter when organizing electronic payments and increasing the reliability of accounting information due to contactless remote removal of information by means of communication interfaces for each subscriber or by means of an individual remote control (remote control).-to reduce the hardware costs of servicing one subscriber associated with the use of the main units and units of the meter to account for energy consumption for all subscribers, and, as a result, the low cost of electricity metering in recalculation per subscriber.

Objective. The purpose of the study is to analyze the current level of development of the digital infrastructure of the urban planning sector, to identify the features of information technology support for the implementation of the BIM concept at the stages of the life cycle of the CCS and the functionality presented on the national market of solutions that support BIM technology.

 Method. Within the framework of the study, the methods of logical, structural, comparative, system analysis were used; modeling and graphical presentation of results.

Result. It has been established that in the current period, most companies in the Russian architecture and construction industry are considering the transition to a fully integrated BIM as a long-term development format. An objective obstacle to a quick transition is the complexity of complex IT support for BIM processes and the level of current development of digital infrastructure. It has been established that the priority direction for the development of the IT industry in the context of ensuring the implementation of the BIM concept is the formation of a single ecosystem of Russian BIM software. Along with the need to develop competitive Russian software products, ensuring their interoperability and standardization of data exchange formats are highlighted as the main problems. The key parameters for assigning a software product to the BIM group are determined, the levels of maturity of the BIM data exchange process are identified, and approaches to the organization of exchange processes are considered.

Conclusion. The proposed criteria for classifying software products as solutions that support the BIM concept can be used in the formation of functional requirements for the developed import-independent software products. The interpretation of the interoperability reference model in relation to BIM technology can be used to develop the integration capabilities of BIM tools in a single information technology environment of general data, and also become a methodological basis for creating an open national data exchange standard.

Objective. The aim of the research work is to develop a software solution for identifying trends in demand for consumer goods by analyzing big data.

Method. To achieve this goal, the work analyzed the current state of development of the Internet retail market in Russia, as well as the technologies and tools for analyzing big data necessary for designing a software and hardware solution. To evaluate the effectiveness of the obtained data processing model, a sample obtained from open sources is used.

Result. As a result of the study, a technical solution has been developed that allows analyzing the demand for goods in a given time range based on data from open sources.

Conclusion. A software component has been developed to analyze the demand for consumer goods based on order data. The resulting technical solution supports batch processing of data, and the architecture of the infrastructure component allows distributed computing. Testing the tool on a real sample showed the effectiveness of this approach to analyzing consumer demand trends.

Objective. The aim of the study is to build a linear regression model of electricity generation in the Russian Federation depending on resource indicators, which include: the volume of coal and gas production, the production of fuel oil. Statistical data for 2005 - 2020 were used as the information base of the study.

Method. Estimation of unknown parameters of the linear model is carried out using three methods - least squares, modules and anti-robust estimation. They behave differently with respect to outliers in the data. The second of them does not react to outliers at all, completely ignoring them, and the third, on the contrary, strongly gravitates towards them, therefore, these methods are a kind of antagonists in relation to each other.

Result. Three alternative models of a linear regression model of electricity production with high accuracy are obtained. The value of the parametric stability index of the data sample, based on the properties of the parameter estimation methods, is calculated. Observations are identified that correspond to the maximum and minimum extent to the linear model on the analyzed sample. The values of the contributions of the factors to the right parts of the models are calculated.

Conclusion. Three versions of the model built by different methods can be successfully used to solve problems related to forecasting the production of electricity in the country. At the same time, the variant constructed by the least squares method is a kind of compromise.

Objective. The purpose of the study is to identify the main causes of the growing shortage of personnel resources of territorial divisions of internal affairs bodies (ATS) and appropriate methods of their elimination.

Method. When searching for the causes of the personnel shortage of the ATS, the procedures of system analysis were used, on the basis of which the central problem of the staffing of the ATS was identified, a number of tasks and goals were formulated, for the solution of which additional material resources are not required. Mathematical methods of system dynamics were used to solve most problems.

Result. In the work, based on the analysis of the operational situation, regulatory and methodological support of the management activities of the internal affairs bodies, it is concluded that there is a systemic problem: the dynamism of the management system of the internal affairs bodies is disrupted, as a result of which the effectiveness of the management process decreases, leading to an increasing trend of a shortage of ATS units. To solve the identified problems, the authors propose the following technologies: calculation of the profitability of the work of territorial divisions of the Ministry of Internal Affairs of Russia, which allows to assess the necessary and sufficient level of efficiency of the use of all types of resources in the performance of official tasks; development of a methodology for calculating the personnel needs of territorial divisions of the Ministry of Internal Affairs of Russia, taking into account the complexity of their activities, workload and regional characteristics; introduction of a new approach to assessing the activities of divisions The Ministry of Internal Affairs of Russia, based on the separation of the reporting system and the evaluation system, improving personnel policy in terms of making the service in the Department of Internal Affairs more attractive, taking into account the new values of modern society. For each presented task, its own tools and solution technology have been developed.

Conclusion. The solution of the identified tasks will ensure the uniformity and "feasibility" of the workload of its employees, the transparency of the assessment of their activities, which will increase the motivation for conscientious work. Coupled with the improvement of personnel policy to make the service in the internal affairs bodies properly attractive, the expected synergetic effect will reduce the severity of the problem of personnel shortage.

Objective. The aim of the study is to develop an algorithm for monitoring forest fire zones, carried out by unmanned aerial vehicles (UAVs).

Method. The study is based on methods of algorithmic support, methods of analysis and synthesis of automated control systems for technological objects.

Result. The technologies and methods for monitoring forest fires are considered, which confirms the relevance of the use of UAVs to perform these tasks. An algorithm for the use of UAV swarms for monitoring forest fire zones is presented. The algorithm includes enlarged stages of decomposition of the global problem, distribution of tasks, application of methods of collective decision-making, etc.

Conclusion. The proposed algorithm can be implemented subject to the development of swarm control theory.

The aim of the study is to create a virtual test bench, consisting of optimal design parameters that provide the maximum approximation of the real drying process to the experimental data.

Method. Methods of modeling, formalized description, optimal design and management of technological processes and productions are applied.

 Result. A virtual test bench has been developed that allows real-time determination of the design parameters of drum-type dryers depending on the kinetic patterns of the drying process of various grain crops. As an object of study, the design of a two-section drum dryer was used, each section of which is equipped with a profile channel nozzle that provides a transverse supply of the drying agent through the pouring movable layer of the dispersed product to be dried. An algorithm for calculating the drying process is presented, which makes it possible to determine the fields of temperature and moisture content of grain in a wide range of regime parameters. With the use of CAD, a computer model of this installation was made with the possibility of autonomous rotation and movement of the drums relative to each other. A diagram of the synchronized operation of the moving elements of the installation under conditions of operational reconfiguration of its design in accordance with changes in the kinetic curves has been drawn up.

Conclusion. The presented virtual test stand adequately and with high accuracy allows simulating the process of drying materials in a drum dryer; allows you to test the operation of a drum dryer at the development stage, conduct experiments with the highest possible accuracy, select the optimal drying modes for various materials with minimal energy consumption.

Objective. The influence of the nature of the descending branch of concrete compression and stretching diagrams on the ultimate load-bearing capacity of bent cross-section reinforced concrete structures under various loading conditions close to destruction according to the nonlinear finite element model is investigated.

Method. The solution is performed by the finite element method in a physically nonlinear formulation using N.I.Karpenko's deformation theory. Deformation diagrams are used with different steepness of the descending branch. Calculations are performed by a step-by-step iterative method of successive loads on a layered model.

Result. The results of numerical calculation of slab reinforced concrete elements under various conditions of physical nonlinearity of concrete are presented.

Conclusion. The insignificant influence of the steepness of the descending branch on the load-bearing capacity of plate bendable structures has been found and the use of simplified diagram dependencies is fully justified for numerical calculations using a nonlinear model.

Objective. The purpose of these studies is to determine, on the basis of the developed models describing seismic impacts, the most acceptable for acceptance from the point of view of the accuracy of the description of the seismic oscillation both in the shape of the envelope and in duration and frequency characteristics.

Method. The use of empirical models in describing soil fluctuations as a random process has been considered in a number of papers. This paper presents the main simplifying assumptions used in this approach. The validity of empirical models and some difficulties encountered in modeling the oscillation process are investigated.

Result. A methodology for assessing the reliability of the proposed impact models is proposed. The proposed method takes into account the soil - geological characteristics, as well as spectral data of instrumental recordings of known earthquakes.

Conclusion. The seismic impact model, as well as the approximating modeling function, should be determined by the degree of responsibility of the building.

Objective. The purpose of the work is the practical approbation of a nondestructive thermal imaging method to identify hidden (invisible) defects and qualitative analysis of the thermal protection of a complex of construction objects in the city of Vologda, as well as the study of some physical (thermophysical) indicators (coefficients of thermal conductivity, thermal resistance (thermal insulation) and heat transfer) of structural building material in the form of silicate brick.

Method. The fundamental laws of the theory of heat transfer, thermal nondestructive testing, infrared and technical diagnostics, the current domestic regulatory and technical and regulatory documentation, field experiments on real objects and laboratory samples.

Result. The results of the practical determination of hidden defects in the thermal shells of the complex of civil and industrial buildings functioning in the urban environment, thermophysical properties (coefficients of thermal conductivity, thermal resistance (thermal insulation), heat transfer) of modern building materials by methods of thermal non-destructive testing are presented. The locations of identified invisible defects of thermal protection of the surveyed construction objects are determined and recommendations for their elimination are proposed. The obtained values of thermophysical characteristics for the studied structural building material are consistent with the data of current regulatory documents.

Conclusion. The features of the nondestructive method of infrared thermography in determining the hidden defects of the heatshielding shells of operated buildings of various functional purposes and the complex of thermophysical parameters of modern structural building materials are shown. The demand for thermal imaging during energy and technical surveys of construction objects, their individual structural elements, life support engineering systems, as well as studies on the refinement, quantification and prediction of various thermal properties of building materials and products has been experimentally confirmed.

Objective. The purpose of this study was to create new pre-fabricated membrane-rod structures and non-linear methods for their calculation.

Method. A stepwise method with an iterative numerical Euler-Cauchy procedure of the third order of accuracy was applied with the use of the finite element method at the step.

Result. A technique for static calculation of membrane-rod structures has been developed, taking into account nonlinear factors. A calculation algorithm has been compiled and a program for calculating such structures has been written according to it. For this program, a certificate was obtained on the computer No. 2017613415 "Program for calculating membrane-pneumatic structures, taking into account non-linear factors by the iterative method of incrementing parameters."

Conclusion. It is recommended to use a one-step calculation of membrane-rod systems with five iterations per step or a multi-step calculation with five steps with one iteration per step. Mixed options are also effective.

Objective. The properties of road bitumen, when interacting with the components of building compositions, are always transformed relative to their original properties. Therefore, when working with materials based on filled bitumen compositions, regardless of their field of application, the main task is to monitor the dynamics of changes in characteristics and control in the required direction, as well as maintaining properties such as viscosity, flexibility and fluidity. The purpose of the work is to study the effect of modifying additives of various bases (fillers, plasticizers and waxes) on the properties of a bituminous binder and to evaluate the effectiveness of their contribution to the formation of filled bitumen compositions for the construction industry.

Method. The methodological basis of the work is the principle of bitumen structure formation. Experimental studies were carried out using standard and special methods.

Result. The results obtained showed that fiberglass fiber proved to be the best filler in the bitumen composition. In the study of plasticizers, it was revealed that the most pronounced positive plasticizing effect is observed from the use of an extract of selective oil purification, which allows you to control the flexibility of the system in a wide range. It has been established that the plasticizer polyalkylbenzene effectively regulates the properties of the composition at negative temperatures, slightly affecting the heat resistance. The results of the wax study show that Titan synthetic wax and Viscobit polyethylene wax are evenly distributed in the volume of the bituminous binder and provide stabilization of the system properties.

Conclusion. In the process of performing the study, as well as analyzing the results obtained, 3 groups of bituminous matrix filler additives were studied. It has been established that the directed regulation of the properties of bitumen systems is possible due to the rational choice of the type of additive-filler. Thus, using complex fillings of the bitumen matrix when designing bitumen compositions with the possibility of regulating and normalizing their properties (optimization indicators), it is possible to obtain economic and operational effects.

Objective. The article presents the results of experimental studies on the effect of a high-potential electrostatic field on the combustion of liquid fuel.

 Method. Experimental studies were carried out on the developed laboratory installation, which makes it possible to ensure the combustion of liquid fuel in a high-potential electrostatic field with the possibility of changing the polarity. The change in the polarity of the applied voltage to the electrode system of the experimental setup led to an increase in the fuel burning rate in the first case, and to its attenuation in the second.

Result. In this paper, studies have been carried out proving the effect of an electrostatic field on the burning rate and reducing the content of harmful components (soot and carbon monoxide) in fuel combustion purges. Based on the values of the fuel burning rate obtained as a result of the experiments, graphic dependences were constructed on the applied voltage, on which the areas of linear and non-linear changes in the combustion parameters were identified.

Conclusion. The results of the research carried out can be used to create new highly efficient burners for liquid fuel boilers. The effect of reducing the burning rate can be used to create fire safety devices that block the spread of flame during a fire.

Objective. Development of compositions of vermiculite concrete and fibro vermiculite concrete with volcanic pumice. Investigation of the construction and technical properties of the developed compositions of vermiculite concrete and fibrovermiculite concrete with volcanic pumice under the influence of elevated temperatures.

Method. Methods of increasing the fire resistance of reinforced concrete structures are considered. The research is aimed at the development of vermiculite concrete and fibro vermiculite concrete with volcanic pumice for fire protection of building structures and the manufacture of heat-resistant products and structures. To reduce the cost of vermiculite concrete, its partial replacement with volcanic pumice is proposed. For the study of vermiculite concrete with volcanic pumice reinforced with basalt fiber, a rotatable plan of the second order of the regular hexagon type was used.

Result. Replacing a part of an expensive aggregate (expanded vermiculite) with pumice leads to a slight increase in the average density of the composite, while the bending and compressive strength increases. In addition, the heat-resistant properties of vermiculite concrete with pumice are increased. This is due to the fact that volcanic pumice, being a hydraulically active additive, is able to react hydration with cement components, eliminating the harmful effect of secondary hydration of free calcium oxide. The influence of the heating temperature on the change in the construction and technical properties of vermiculite concrete and fibrovermiculic concrete, including with the addition of pumice, has been studied. It was found that dispersed reinforcement with basalt fibers reduces shrinkage deformations, when heated to t = 800, the shrinkage decreases from 0.7 to 0.5% compared to the original concrete matrix.

Conclusion. The dependence "compressive strength = f (average concrete density)" significantly depends on the presence and ratio of pumice in the composition of vermiculite concrete, while an increase in the holding temperature to 600 oC or 800 oC leads to a decrease in the compressive strength from 15 to 25%, and the main decrease occurs when heated to 600 oC, further the increase in temperature has a negligible effect. The dependence of the bending strength on the compressive strength is generally maintained regardless of the heating temperature, and the heating of concrete does not reduce the relative bending strength, i.e. the ratio of bending strength / compressive strength is not reduced. Dispersed fiber reinforcement increases the relative bending strength by about 70% regardless of the heating temperature.

Objective. At present, increased requirements are imposed on waterproofing materials used in seismic hazard zones. The aim of the study is to assess the possibility of using LOGICBASE™ polymer membranes in regions of increased seismic activity in the Russian Federation.

Method. The mechanism of operation of polymeric membranes in foundation structures under conditions of constant displacement and friction is considered. Experiments were carried out to determine the coefficient of friction according to the method of state standards on a tensile testing machine MIRK-1000K. Samples of a round shape made of polymeric membranes were studied on a special multiaxial stretching device in accordance with the requirements of state standards.

Result. Multiaxial tensile testing of LOGICBASE™ V-SL polymeric membranes revealed that the maximum tensile strength of the samples was 6948.22 kPa (~ 6.95 MPa), and the elongation of the samples at break was 113.89%. The coefficient of friction in the system "polymer waterproofing material - concrete structure" was determined under conditions of increased seismic activity according to the MSK-64 scale.

Conclusion. According to the studies, it was concluded that PVC membranes for engineering waterproofing can be used in construction areas with seismicity up to 9 points inclusive on the MSK-64 scale.

Objective. This article discusses spatial large-span structures; provides features of their work; as well as layout examples. General dimensions and ways of stabilizing displacements are given.

Method. The features of the work and layout of spatial large-span structures; as well as calculation formulas are given. The types of sections and nodes of conjugation of elements are presented. A technique is described that allows stabilizing the movements of largespan pavements.

Result. The given structural schemes; as well as the analysis of their work; allow designing large-span spatial systems in the form of convex and concave structures that have high reliability; minimal weight; and high manufacturability in manufacturing; transportation and installation.

Conclusion. The proposed rational design solutions make it possible to reduce the own weight of spatial convex and concave coatings; which have the necessary rigidity; strength and stability. The types of structural schemes; sections and junctions of elements considered in the article are widely used in the practice of design and construction.