The article analyzes technological violations committed due to untimely clearing of snow from railway tracks at stations. Based on statistical data, a graph was constructed depending on the number of violations and their duration. It has been established that in the Novosibirsk region over four winter periods from 2019 to 2023, about 40 % of the total number of stations are weather-sensitive and are at risk of train delays. The maximum number of violations was recorded at Ob station, while their maximum duration was observed at the Inskaya station.

   The main objective of the study is to assess the risk of train delays for reasons related to untimely clearing of snow from railway tracks at stations, by constructing a risk matrix and developing recommendations for its reduction.

   For the railway stations of the Novosibirsk region of the West Siberian Railway, the acceptable level of risk of train delays was 0.104 (train-hour)/year, which is consistent with regulatory documents. It was also determined that the actual level of risks in the region does not exceed the acceptable level. A matrix of risks of train delays due to reasons related to untimely clearing of snow from the railway tracks of stations has been constructed and stations have been identified whose risk level is recommended to be reduced: No. 1, 4, 8, 9, 11, 13, 16 and 20. For each risk level, recommendations have been developed aimed at reducing the frequency of violations and the duration of train delays. It was also possible to determine the boundaries of a broadly acceptable level of risk and railway stations that do not require the development of short-term risk reduction measures in the presence of violations.

   The article is devoted to the development of a methodology for supporting decision-making on the feasibility of converting automotive equipment to run on compressed or liquefied natural gas.

   The main technical, economic and environmental effects achieved when converting automotive equipment to run on natural gas are shown. The current situation in the country with gas filling stations and the resulting restrictions on the use of natural gas as a motor fuel are described. Cases are listed that exclude the possibility of converting automotive equipment to natural gas. It has been determined that the factors that must be taken into account when calculating the technical and economic efficiency of converting automotive equipment to run on natural gas should include the characteristics of automotive equipment, standard and actual fuel consumption, the cost of conversion to run on natural gas, the cost of motor fuel in the region of operation , costs associated with the maintenance and repair of equipment after switching to gas engine fuel, as well as retraining of service personnel, costs associated with re-mileage due to the remote location of automobile gas filling compressor stations or cryo-gas stations, the availability of federal and regional subsidies, preferential rates transport tax and other additional measures to stimulate the development of the gas motor fuel market. Examples of calculations using the presented methodology for the fleet of automotive and tractor equipment Russian Railways are given. An assessment of the influence of such factors as annual mileage, the ratio of the cost of motor fuels and an increase in the distance to gas stations on the payback period of the project of converting automotive equipment to run on natural gas is presented.

   The purpose of the work is to study the quality of the transportation network (TN) functioning depending on external and internal factors, to search for bottlenecks in the TN, to consider the network from the point of view of matching transportation supply and demand.

   Random flow of events, such as traffic accidents, overloading of highways, repair and construction works, etc. generates phenomena of wave character, spreading through the network and creating derivative problems.

   The task is to identify the objects of transport infrastructure, the importance of which is critical from the point of view of their significant impact on the stability of the transport system as a whole.

   The specificity of transport systems of large cities and agglomerations makes it necessary to consider this problem more closely, taking into account their peculiarities in various aspects: from the point of view of TN security it is necessary to find the most vulnerable elements of the transport network both among the many nodes and among the many communications; from the point of view of reliability it is necessary to ensure the normal operation of TN within the permissible limits; from the point of view of sustainability it is necessary to have such a structural and functional organization of TN, which will allow for external and internal disruptions in the transport network. Practical application of the research results can be used in transportation planning, development of master plans for urban development, reconstruction of existing transport infrastructure, to improve transportation security systems, development of intelligent transportation systems.

   At the present stage, the significant development of automation and telemechanics systems has led to a variety of railway network operation modes, in connection with that a more detailed study is required to determine the potential of interval train control systems to improve the efficiency of the transportation process on single-track railway polygons.

   The aim of the work is to evaluate the efficiency of different variants of interval regulation on single-track polygons in conditions of traffic size growth and destabilising factors combinations in comparison with transition to a double-track configuration of the polygon.

   Multi-approach modelling is used to simulate the operation of the polygon, including application of process approach for simulation of on-duty personnel actions on train passing, agent-based modelling for simulation of train mode selection and system dynamics for real-time traction calculations. The approach to estimation of interval regulation efficiency application on the basis of indicators and configuration matrices analysis of single-track polygon is offered. In a double-track configuration of the polygon, increasing traffic sizes, coupled with destabilising factors reduce the route speed, while in a single-track configuration, in addition to slowing down the train flow, they cause a capacity deficit leading to an increase in the amount of required infrastructure. Significant improvement of indicators and reduction of requirements in additional infrastructure at single-track configuration provide transitions from traditional autoblocking with «fixed» blocks to virtual coupling and from autoblocking with «moving» blocks to coordinate system of interval regulation. Interval regulation on a single-track polygon can become one of the effective tools of transport process intensification, allowing to reduce extensive increase of the polygon infrastructure. It should be noted that there is no universal variant of interval regulation for single-track polygons and it's necessary to change the existing infrastructure to maximise the potential of this technology.

   For the economy of the Russian Federation, the transportation of dangerous goods in international and domestic traffic plays an extremely important role. Natural gas (dangerous goods of class 2), ammonium nitrate fertilizers (dangerous goods of class 5), fuel elements (dangerous goods of class 7) and many other cargoes are supplied to dozens of countries around the world. All types of transport are involved in this process: pipeline, railway, automobile, river and sea, aviation. Incidents, accidents and catastrophes involving dangerous goods with severe consequences continue to occur on all modes of transport in almost all regions of the world. An analysis of a number of current accidents and emergencies, as a result of which not only critical or significant damage was caused to important transport infrastructure facilities, but also environmental damage to the population of adjacent territories, led us to the conclusion that the existing protection system is insufficient and it is necessary to develop new significant elements of it. Taking into account the new circumstances of the protection system in emergency situations with dangerous goods is, in our understanding, primarily in the prediction and management of fire and explosion modes of highly dangerous substances in order to reduce environmental and other negative consequences. Dangerous goods of Classes 1, 2 and 3, as a rule, have highly dangerous properties. Methodological flaws have been identified in assessing the impact of explosion and fire consequences of dangerous goods and minimizing their consequences. Based on characteristic examples, an attempt has been made to simulate the combustion and explosion of a dangerous cargo of vinyl chloride, calculate the amount of toxic products formed and the dangerous concentrations formed by them in the air of the emergency zone. Possible modes are considered and an estimated parameter is proposed – the calculated relative index of toxicity under various modes of destruction and conditions of combustion and dispersion of products. The expediency of developing a methodology for predicting the environmental consequences of man-made emergencies (fires and explosions) with dangerous goods is justified, the purpose of which is to develop additional protection measures in emergency situations, including protection of residents of residential areas, based on a model of formation of toxic products in a chemical reaction and their spread in the air.

   Due to the state program of the Arctic zone development of the Russian Federation, it is planned to build new bridges and various hydraulic engineering structures. For the development of these territories, a large number of ice crossings and winter (ice) roads are built annually, since most of the large (navigable) rivers lower courses of in the Siberian and Far Eastern regions are located in hard climatic (northern) conditions. In connection with the above, the article provides an overview of the works of ice impacts estimation on bridge piers and other railway and motorway engineering structures (R&M ES). Not only does freshwater ice differ significantly from sea ice in its physico-mechanical properties and crystal habit, but ice in the same river in the upper and lower reaches may also differ due to an indefinite number of influxes of different chemical composition. For this reason, the problem of ice fields interaction and bridge piers, approaches to the strength assessment of river and technical ice is very relevant and extensive. The article discusses various mechanisms of freshwater ice destruction in contact with the surface of the piers on the rivers flowing through the territory of the Russian Federation. There are given diagrams of the vertical and horizontal cracks formation in the contact zone of ice and supports. It is also pointed out that it is necessary to consider the scale effect, that has a significantly alleets on the results of the strength characteristics assessing of ice. Both existing engineering methods for calculating and modeling ice behavior according to reference documents and refined calculation methods are considered, taking into account the anisotropy of the physical ice properties, its elastic-plastic behavior and elastic-plastic behavior during deformation. Prospective approach to the derivation of ice strength criteria are noted, and possible ways of further research are shown.

   Designing power transmission poles that ensure uninterrupted power supply and trouble-free operation at minimal cost is an urgent and important task. The article presents the results of research on the optimization of the structural system of an intermediate power line support in a metal design. The type of support was chosen based on a review of statistical data, which showed that the destruction of intermediate supports is the largest percentage of the total number of failures of all supports in the whole. The article presents the results of studies of the effect of the type of lattice of the trunk of a metal intermediate transmission line support of type 1P220-2 on its mass, the number of nodal connections, as well as reliability parameters such as strength, rigidity and stability. According to the results of calculations, a semi-bevel and cross lattice of bent-welded square profile elements has optimal parameters, which is recommended for elements operating on conditional central tension and compression. The dependence of the width of the base of the metal support on its overall height is investigated. It is noted that the large width of the base makes it difficult to install and transport the support, since it affects the length of its lattice elements. The effect of changing the width of the trunk in height on the weight of the support as a whole is considered. It is noted that the constant width of the trunk makes it possible to unify the lattice elements, which reduces the total cost of manufacturing the support.

   In the last decade, the development of international relations, the growth of the Russian economy, the reorientation of the flow of goods transported by rail from West to East have set new tasks for the reconstruction of the Baikal-Amur and Trans-Siberian Railways, and conducting pre-design studies on the North Siberian and Central Asian international roads , in particular, to improve methods for calculating structures, railway track elements, and the stress-strain state of concrete and reinforced concrete structures. The article attempts to evaluate the bearing capacity of two sub-types of widely used sleepers (S3-D and S3-D 4×10) from the perspective of calculating reinforced concrete structures using the general method. Thus, all the prerequisites and necessary dependencies were used in the general case of calculating the normal cross-sections of bent elements for any cross-section shapes and reinforcement. Studies have been conducted for concrete compressive strength classes B40 and B55. It is shown that sleepers of the S3-D subtype in the sub-rail section have a higher bearing capacity than sleepers of the S3-D 4×10 subtype. The results of the study also showed that for reinforced concrete sleepers of subtypes S3-D and S3-D 4×10, an increase in the concrete compressive strength class does not significantly affect the bearing capacity of structures.

   The purpose of this work is to select the optimal shape for sharpening dowels intended for fire driving and to develop a methodology for assessing and predicting the depth of driving a dowel of a cross-shaped cross-section using mounting guns.

   Both problems were solved on the basis of experimental data obtained from repeated driving of dowels using a modified PC 52-1 construction gun. In the first case, the density of the seating socket obtained after driving the dowel and the manufacturability of the dowel sharpening process were taken as the criterion for the optimal sharpening shape. During the experiments, a large number of cross-section dowels with a wide variety of sharpenings were driven in, as well as previously known dowels, such as the dowel of N. F. Kotov. The conducted studies showed that the most suitable for fire hammering is a cross-section dowel with a knife conical sharpening. Predicting the driving depth was based on experimental data obtained by shooting dowels of various transverse sizes into pine wood beams with a cross section of 10 by 15 cm, located on a concrete base. At the same time, the dependence of driving depth on the power of the cartridge and the moisture content of the timber was studied. To predict the driving depth, it is proposed to use an exponential approximation of the dependence of the driving depth on the transverse dimensions of the dowel. This proposal is well supported by experimental results. Constants have been determined that characterize the speed of reduction in driving depth for D-1 cartridges when driving 25 % moisture content into pine wood and for D-2 cartridges when driving 15 % moisture content into pine wood.

   The article presents the results of surveys and tests on a railway bridge with spans of through main trusses, with an estimated length of 66 meters, after replacing a failed element in the upper belt. The survivability of the superstructure, due to the spatial redistribution of forces between the intact elements and the excess strength of the components in relation to the applied loads, has made it possible to prevent a progressive collapse of the structure and even allow trains to continue operating on the Trans-Siberian railway for a period of time. The article experimentally investigates the factors that influence the stress-strain state of truss structures. The preliminary examination was conducted using the laser scanning technique, which resulted in the generation of a point cloud that covered all the structures of the supports and superstructure. The tests were conducted under passing loads. During the tests, the deflections of the trusses, the vertical displacement of the support parts, and the fiber stresses of certain elements of the superstructure were monitored. It was found that the superstructure had geometric deviations in the form of tilts of vertical elements up to 110 mm and misalignments of support points up to 18 mm in height. The tests revealed a complex stress-strain state of the structure and an uneven distribution of stress across the truss elements, which deviated from the traditionally assumed design assumptions. Many truss elements were working in compression with bending, with bending stresses exceeding axial stresses. While the overall deflections of both trusses were similar, the fiber stresses in the elements of extreme panels consisted of bending deformations up to 70 %, more typical of truss belts. Uneven settlement of the supporting structures under load was observed, with a difference in settlement of more than two times. Based on this observation, the article draws conclusions about the factors that may have caused the failure of the load-bearing components.