Introduction. Clearing the territories of populated areas from fallen snow in winter is an urgent task. Its effective solution is necessary to ensure road safety and mobility. From the point of view of environmental safety, it is expedient not to remove the collected snow to special landfills, but to provide its melting and discharge of resulting suspension into treatment facilities by the applying of specialized installations. On the example of Tyumen city, it is shown the significant scale of environmental damage that can be caused by the use of snow-accepting landfills (dumps).

Materials and methods. The method of research on the models having the same physical nature with the original (physical modeling) is considered to be the most acceptable, as the whole cycle of the process depending on the full complex of influencing parameters can be reproduced and fixed on the models. The scientific basis of physical modeling is the theory of similarity and analysis of dimensions, which allows, by means of interdependence of dimensionless complexes characterizing the studied process, to generalize the obtained experimental values and to extend them to similar technical systems.

Results. Based on the analysis of the operating process of snow melting plants the authors propose a design that provides greater melting intensity due to the installation of activators.

Discussion and conclusion. The design performance was tested and the influence of the main parameters on the dynamics of the operating process was assessed. The geometric and kinematic parameters of the working process activators were established, which move according to the principle of a Segner’s wheel due to the jet streams of the heater affecting the snow and ice massif.

Introduction. Successful quality control plays a crucial role in pavement compaction work. The main tool for continuous compaction monitoring is the frequency analysis of the vibratory acceleration spectrum of the roller. There are several indicators that are determined by the different harmonics of the acceleration frequency spectrum use. However, these indicators have a number of disadvantages, among which are low accuracy and limited scope of application. The aim of the study is to develop a universal compaction indicator that eliminates these disadvantages.

Materials and methods. A single-mass oscillatory model describing the interaction of the system “vibratory roller – soil” has been created in Simulink environment. The model allows changing the soil parameters, such as stiffness and viscosity, as well as the operating parameters of the vibratory roller – amplitude and frequency of vibration. Fast Fourier transformation was used to study the frequency spectrum of roller acceleration.

Results. As a result of modeling, frequency spectra of acceleration of the vibrating roller for different modes of roller operation were obtained. Through the analysis of the obtained data, a new indicator of compaction degree was proposed.

Conclusion. On the basis of the proposed indicator the technique of determining the moment of time change from the periodic loss of contact (the partial uplift mode) to “double jump” mode is developed. Implementation of the methodology in operating performance will improve the efficiency of the process of soil compaction by a vibratory roller.

Introduction. A steady trend in the development of automobile engines’ designs was defined, which involves the widespread use of superchargers and coolers of the supplied air, providing the increase in technical, economic and environmental performance characteristics of motor vehicles. An urgent problem of efficiency reduction of the charge air coolers, due to the formation of impurities on both the outer and inner surfaces in operation was described. The results of scientific papers’ review in the field of improving the operation efficiency of automotive heat exchangers were presented. The purpose of the scientific work was formulated, the list of tasks to be solved was defined.

Materials and methods. The theoretical statements describing the parameters of heat exchange processes at the boundary of two environments separated by a multilayer wall were presented. Calculation formulas have been determined allowing to define the influence nature of thermal conductivity and the thickness of contaminant layers on the surfaces of the heat exchange device on the volume of heat flow discharged by this device into the environment. A hypothesis has been put forward about the formation character of contaminant layers and about the existing value of their maximum thickness corresponding to the minimum of operational thermal conductivity. Methods of conducting experimental research and diagnostic equipment that ensures research performance aimed at obtaining the data necessary for the practical implementation of the developed theoretical statements were described.

Results. The dependences of the thickness of the contaminant layers formed on the outer and inner surfaces of the charge air cooler in operation are given. The values of the thermal conductivity coefficients of outer and inner contaminants have been established, which is one of the points of scientific novelty. The obtained values were used to model the processes of heat removal from charge air and to develop measures aimed at improving the efficiency of vehicle operation. The article presents the results of modeling the heat flow discharged from the charge air and provides recommendations for enhancing the operation capacity of turbocharged engines.

Discussion and conclusion. The solution of the determined goals was presented, the indicators reflecting the achievement of the research objective were defined, the results reflecting the new scientific accomplishments in the study were obtained. A brief description of practical recommendations aimed at improving the operation efficiency of turbocharged diesel engines was given.

Introduction. The research is aimed at developing a methodology for determining the optimal location of material flows’ distribution center, taking into account the formation of ring routes based on the use of the fictitious nodes and branches’ method (FNB), in order to minimize overall logistical costs. Despite the sufficient number of existing ways to solve this problem, they have some disadvantages: they are not entirely realistic and do not completely meet the requirements of logistical optimization. Namely, existing algorithms do not take into account the need to visit the branches of the transport graph several times and the curvature of the movement trajectory.

The developed technique has greater practical application because it deals with determining the optimal location of the distribution center based on the criterion of full vehicle loading, using piecewise linear approximation to account for the curvature of routes, forming delivery routes using the accurate fictitious nodes and branches’ method (FNB) to optimize transportation and minimize overall logistical costs. This technique can be used by both providers to analyze and select the location of a logistics distribution center taking into account the formation of optimal routes for the delivery of goods, and by owners of large retailers.

Materials and methods. The developed methodology includes several stages. At the first stage, the area of the most probable location of the distribution center (DC) is determined. We calculate the coordinates of cargo center of gravity using the formulas for the strength of materials. As its weight, we take the amount of cargo in receiving points. We accept the hypothesis that the placing area for distribution center is located around the cargo center of gravity. Its boundary passes through the nodes closest to it. The nodes are cargo points, road intersections and points of abrupt changes in the direction of movement. The expert can assign additional nodes to clarify the influence of geometry, length, and other parameters of the trajectory of movement. As a rule, there is no road between the center of gravity and the nodes. At the second stage, a rational location of the regional center is determined. There is no road between the center of gravity and the nodes. Therefore, ring routes are calculated that originate from nodal points using the method of fictitious nodes and branches. The routing problem is reduced to finding one ring that passes through the selected nodal point several times. The constraint is taken into account by the blocking method. At the third stage, we replace the branches of the curvilinear route of movement with piecewise linear interpolation. We determine the transport work and the coordinates of the center of gravity of the rectangular diagram on each branch of the route. We find the value of the total transport work around the coordinate axes. We calculate the coordinates of the regional center. We accept its rational coordinates according to the average values obtained for each selected node.

Result. The application of the developed methodology for the network delivering goods from the distribution center to the Public Joint Stock Company “Magnit” trading points per shift has reduced the number of routes, time on the route by 10% and the length of the route by 16%.

Conclusion. The methodology for determining the optimal location of the distribution center of material flows has been provided. The program has been developed on the basis of the proposed methodology. Results of the use of the proposed methodology have been obtained by testing on the example of Public Joint Stock Company “Magnit”.

Introduction. During the operation of cars and other vehicles, the process of changing technical condition of parts and units takes place. With increased operation time and mileage, the failure rate increases, which leads to the problem of maintaining equipment in working condition through high-quality maintenance and repair. Parts repair has been a way to extend the service life of equipment by replacing or restoring the worn parts. Due to the problems of quality supply, the urgency of restoration becomes obvious. Numerous problems with high-quality spare parts cause the restoration as a way to overcome the above-mentioned problems. However, the restoration method should meet certain requirements, in particular, repair costs should not exceed 50% of the cost of a new part and durability should be at the level of 80-100% of the new part. Therefore, this article presents the results of research on a new method of restoring parts with iron-chromium coatings in order to maintain equipment in good condition.

Materials and methods. The investigation was based on literature analysis to study the restoration methods according to various criteria, such as durability, cost of use, wear resistance and other indicators. Also, based on a preliminary analysis, one of the promising methods was selected – iron-chromium coating. Preliminary research into the effect of acidity on the performance and quality of the coating has been carried out.

Results. The study of iron-chromium coating obtained from the composition of an electrolyte with 0.4-0.6 acidity has made it possible to obtain a coating with a sufficiently high microhardness (up to 8,500 MPa), current output (up to 40%) and deposition rate (up to 200 microns/hour). The resulting coating also has demonstrated a small number of microcracks, which made it possible to delay lubrication and provide increase in wear resistance.

Discussion and conclusion. As a result, the coating obtained has shown good physical and mechanical properties. Therefore, it will be possible to use this method to restore the mounting area of bearings in transmission shafts operating under abrasive wear.

Introduction. The study aims to analyze modern automatic passenger counting methods in public transport. The study addresses the pressing issue of passenger flow counting in public transport using modern technologies such as video surveillance, infrared sensors, and LiDAR.

Materials and Methods. An overview of technologies is provided, including sensors, cameras, LiDAR, and RFID, along with analysis methods based on theoretical and empirical approaches. Information from development companies is used to compare the accuracy of technologies in real-world conditions.

Results. The comparison results indicate that LiDAR and cameras with machine learning offer the highest accuracy, particularly in high passenger density scenarios. Wi-Fi and Bluetooth-based technologies have limited accuracy, but combined solutions can overcome their drawbacks.

Discussions and Conclusions. The conclusion emphasizes that LiDAR and video surveillance with machine learning are the most effective for accurate passenger counting. Further testing of combined technologies and the development of flexible systems are recommended, along with innovative approaches in neural network training to enhance accuracy.

Introduction. For urban agglomerations, public transportation is of crucial importance - it provides mobility of population at minimal cost and within minimum urban space, acceptable negative environmental impact being achieved. This paper considers the problem of estimating passenger carrying capacity of vehicles for operation on urban public routes. The solution is based on determining optimal ratio between parameters of efficiency and quality of public transportation.

Materials and Methods. In this article based on empirical data from transport organizations it has been shown that the cost of bus operation is linearly dependant on its capacity. On the other hand, the costs per passenger-seat are of non-linear character. With the same tariffs to ensure profitable transportation buses of smaller capacity should be operated with a higher degree of passenger compartment occupancy, as a result the quality of transportation suffers. Recommendations on selecting vehicle passenger carrying capacity for operation on urban regular routes taking into account the unevenness of passenger flows, as well as the influence of the used class of rolling stock on the efficiency (economic parameters) of the transportation process have been given.

Discussion and conclusion. The effectiveness of the developed methodology for determining the passenger carrying capacity of rolling stock to operate on regular urban routes is shown based on test calculations for a real route of Krasnoyarsk city.

Introduction. The existing traffic conditions in major Russian cities do not allow us to meet the high demand on the quality for passenger and cargo transportation. The speed of movement during peak hours decreases significantly and on some sections of the network corresponds to the pedestrian speed. The excessive volume of private transport movements requires the implementation of a set of measures aimed at the development of urban public passenger transport. One of these measures is the allocation of separate lanes for passenger transport. At the same time, the existing regulatory documentation recommends organizing such lanes only on sections of the road network with three or more lanes in one direction.

The purpose of this work is to determine the proportion of the length of the street and road network of cities in which it is possible to organize lanes for public passenger transport without carrying out roadway reconstruction work.

Materials and methods. Method of searching for the “conditional transport center” of the city proposed by the author was used in the process of writing the article. On order to divide the city territory, the method of concentric circles with a step of 1 kilometer was employed. Data on the number of traffic lanes on the road network of 17 cities in Russia and Eastern Europe were obtained applying the navigation system “Yandex. Maps”.

Results. The data acquired as a result of the study showed that the share of the road network on which it is possible to allocate lanes for passenger transport can reach 40% or more. At the same time, the higher the population of a city, the greater the proportion of streets with multi-lane traffic. In the central part of the largest cities in Russia, the proportion of multi-lane streets reaches 60-80%. At the same time, as we move from the center to the periphery, the proportion of such highways gradually decreases to 10-15%.

The formation of streets with multi-lane traffic was significantly influenced by the historical periods of cities’ development, as well as by the presence of tram traffic now and in the past.

Discussion and conclusion. As a result of the research carried out, it can be concluded that in most Russian cities, the share of the street and road network on which it is possible to organize separate lanes for public passenger transport is slightly higher than the length of traffic jams. At the same time, in the largest cities, such as Yekaterinburg, the length of traffic congestion exceeded the share of multi–lane streets by 1.5 - 2 times. In cities with similar road conditions, the organization of dedicated traffic lanes for passenger transport is not enough to solve transport problems. In these cases, restrictive measures are needed to be implemented to reduce the use of personal automobile transport.

Introduction. BIM (Building Information Modeling) is one of the important examples of sustainable practices that the construction industry in Iraq has recently adopted. Many studies in recent years have discussed advantages and problems of BIM in architectural and construction (AEC) industry. However, there is a limitation in these studies in terms of finding out the advantages and challenges of BIM in sustainable facility management. The research aims to investigate the factors influencing the implementation of BIM for sustainable facility management (SFM) in Iraq's construction sector.

Materials and methods. A thorough review of a variety of research was done to determine the numerous factors that contribute to the advantages and obstacles in BIM for SFM. A questionnaire has been used to interview 119 Iraqi specialists in construction engineering. The relative importance index (RII) was used to rank the advantages and obstacles. Furthermore, the research employed statistical techniques to determine the five most important obstacles.

Results. Three key advantages of adopting BIM in SFM have been identified, particularly, facilitating access to the relevant information, ensuring accurate documentation, supplying a centralized and coherent system for managing construction maintenance, reducing material wastes during the project operation period. Besides, the following three most common obstacles have been distinguished: absence of a cooperative workplace environment, resistance of FM stakeholders to leave its traditional approach of operation, and insufficient support and attention of senior management to environmentally friendly methods.

Discussion and conclusion. The results obtained have demonstrated the need for strategies addressing the challenges and improving efficiency of BIM in SFM. The research provides stakeholders in developing countries with guidance to effectively SFM by promoting the factors that propel BIM adoption and improving facility management by leveraging BIM technology advantages.

Introduction. Timber as a structural material for bridge spans has some advantages compared to currently widespread reinforced concrete or steel. New technological and structural forms of timber spans should comply with modern requirements for load capacity and durability. Compared to foreign practice of timber bridge construction, our experience in this sphere is largely lost or does not correspond to modern conditions. The most advanced design solutions include combined timber-reinforced concrete spans.

Materials and methods. The authors analyze both foreign and domestic experience of making connections in composite timber-concrete structures. The text provides information on the scope of application of timber bridges with combined logs and separately describes the design of a timber-concrete span with combined logs and the test results. Further the authors consider the experience of application of bridges with glulam girders and design solutions for the combined timber-concrete span structure. Based on the survey data for the bridges in Omsk region, the authors present the experience of bridge operation and maintenance for structures with board-nail blocks and driveway slab with a cross-laid beams. The text indicates typical damages of such spans and considers a variant of reconstructing such bridges with reinforced concrete roadway slab jointed with beams.

Results. The authors identified the need to introduce new solutions to increase the durability of timber bridges. One of such solutions is the use of reinforced concrete passage slab jointed with timber beam, which also increases the overall load-bearing capacity of the span structure.

Discussion and conclusions. The designs of timber-concrete spans proposed by the authors in the article have greater durability and increased load-bearing capacity compared to timber spans. This structural method can be effectively applied to the reconstruction of existing timber bridges.