Introduction. The implementation of production and technological processes of machines on the vast territory of the Russian Federation is related to the necessity to operate them in low temperatures conditions. The article presents the results of the applied scientific research of the factors that have a negative impact on the operation process of internal combustion engines at low ambient temperatures. The use of the modern methods and means of diagnostics of the cylinder-piston group and the crank- engine mechanism make it possible to reliably establish the causes of the internal combustion engines failures.
Materials and methods. In the course of the experimental studies the non-destructive testing, organoleptic, measuring and expert methods were used.
Results. As a result of a comprehensive assessment of the engine failures causes, it was found that the breakdowns in the use of inappropriate operating materials at low temperatures, measures to prepare for the launch of diesel generator sets were the main reason for untimely start-up and the faults in cylinder-piston group and the crank mechanism elements, which led to emergency failure of the internal combustion engine.
Discussion and conclusion. The proposed research results will make it possible to specificate the development prospects in the field of providing the reliability of internal combustion engines operation.

Introduction. Add-on compactors for excavators (ACE hereinafter) are replaceable working equipment for excavators. They are used for soil compaction after the backfill of trenches, wells, foundation cavities and other “narrow spaces” of construction, as well as soil compaction at slopes of embankments and excavations.
In practical use of ACE, builders face two challenges:
to justify the choice of an ACE for soil compaction under given conditions determined by the soil type and moisture, layer thickness, and the required compaction factor; to determine the time required to compact soil with an ACE at a single point positional compaction to ensure the required compaction factor of a given type of soil in a layer of required thickness.
The problems above require the information regarding technological capabilities of ACEs in different technological situations of soil compaction. The assessment of such technological capabilities of ACEs, at the same time, should take into account the ongoing transition to a new regulatory framework in Russia in the field of assessment indicators for the results of soil compaction in construction.
Materials and methods. ACE technological capabilities review was conducted based on the information provided on the official websites of the largest Russian and foreign ACE manufacturers and suppliers.
Conclusion. The analysis of information provided by ACE manufacturers and suppliers showed that most of that information is technical specifications of ACEs and excavators. There is almost no information on technological capabilities of ACEs. At the same time, ACE manufacturers and suppliers use ambiguous terminology (for example, “compaction volume”) in the assessment of technological capabilities.
Practical value. Lack of information on technological capabilities of ACEs in various technological situations of soil compaction leads to errors in selection of an ACE model and its operation time during single point positional soil compaction, which increases the risk of under compaction and reduced service life of constructed objects. To solve this problem, the Construction and Road-Building Machinery Department of Yaroslavl State Technical University is developing a methodology for calculating the results of soil compaction with an ACE in different technological situations.

Introduction. High rates of new territories development, the development of the construction and road-transport complex, mining and transportation of minerals is impossible without machinery and equipment. The use of a caterpillar propeller as a base chassis has both advantages and disadvantages. One of the main problems is ensuring the mobility of tracked vehicles. The use of mixed-type power units and transmissions allows solving this scientific problem and ensuring the efficiency of technological operations during the operation of tracked vehicles. Modern vehicles use a variety of transmission types, including electromechanical transmission (EMT). In such a design, torque conversion and change in the speed of the drive wheels of the caterpillar propulsion device are carried out by means of traction electric motors (TEM). The aim of the use of electromechanical transmission in tracked machines is to increase the tractive-dynamic properties and fuel economy and, as a result, to improve the mobility of the machine. The combination of an internal combustion engine (ICE) and electric machines in a caterpillar machine (CM) makes it possible to maximize the advantages of the latter and compensate for the disadvantages of each. These improvements are achieved mainly through the different performance characteristics of the traction electric engine (TEE) and the energy storage device (ESD).
Research methods. A system analysis served as the basis for the theoretical studies. A mathematical model of the motion of a tracked vehicle with an electromechanical transmission has been developed. The methods of the theory of algorithms were used.
Results. A structural diagram of the arrangement of a series connection of elements of an electromechanical transmission of a tracked vehicle, protected by a patent of the Russian Federation, has been developed and presented. An algorithm has been developed for the interaction of its elements taking into account the movement of the machine. The main mathematical relationships included in the methodology for substantiating the operational characteristics of a tracked vehicle with an electromechanical transmission are presented.
Discussion and conclusion. Using the developed approaches and methodology, it will be possible to calculate the components of the electromechanical transmission in order to ensure the required mobility of the caterpillar machine, to assess its fuel economy, as well as its maximum and average speed.

Introduction. This article describes an algorithm developed by the authors for the operation of a crane anemometer that measures the gust rate and average wind speed and determines the predicted wind speed on the basis of it. The main part. The main influencing parameters and their measurement intervals are defined for the construction of the anemometer algorithm. The method of calculation of gust velocity and average wind velocity from the data of the pulse sensor of the helicopter anemometer is presented. The method of wind speed forecasting based on the construction of an extrapolation function is given.
Results. An anemometer program algorithm with extended capabilities relative to existing analogues has been developed. The instrument not only captures the hazard at the moment, but also predicts its future development. On the basis of the analysis of wind dynamics studies, a table has been compiled of the levels of the determined parameters (gust rate, average speed and projected average wind speed) and the signals given to the operator of the crane. For each type of signal, the value of the removal delay is defined.
Conclusions. ZAO KROS Engineering and Technical Centre has made a prototype anemometer using the principles described in this article. The device meets all requirements of the regulatory and technical documentation. Further work on the improvement of the algorithm of its work will make it possible to increase the safety of technological processes carried out with the use of elevated structures.

Introduction. To solve the problem of accelerating the construction of roads, improving their quality, it is advisable to use a continuous action unit to form a underlying layer. The main working elements of this unit are buckets, which cut off the soil layer from below and side. At the same time, the bottom knife cuts off the ground layer from below, the right knife - on the side, and the console knife partially cuts the top layer of soil from below for the next bucket. In particular, the analysis of interaction with the ground of the bottom knife of the continuous action unit is of theoretical and practical interest. To do this, the lower knife is divided into elements and the interaction of these elements with the soil is analyzed. The consistent impact on the soil of many bottom knives, within the width of the grip of the unit, is replaced by the impact on the ground of one conventional bottom knife at a distance necessary for the development of one cubic meter of soil. The forces of interaction of the conventional bottom knife with the soil are called conditional forces.
The method of research. The method of calculating energy costs when introducing the bottom knife into the ground is presented. In general, when introducing the bottom knife in the ground, there are energy costs: to separate the soil, to overcome the friction of the ground on the edge of the blade, to overcome the pressure of the ground on the face, to the rise of the ground, to the vertical acceleration of the ground by the phase, to overcome the friction of the ground on the face, to overcome the friction of the ground on the surface, to overcome the friction of the ground on the lower plane. The total energy costs of interacting with a one cubic metre soil are derived from the addition of private energy costs. The method of calculating the horizontal longitudinal force needed to move the bottom knife is given.
Results. On the basis of the developed method, energy costs are calculated in the introduction of the lower knife: on the separation of the soil, on overcoming the friction of the ground on the edge of the blade, on overcoming the pressure of the ground on the face, on the rise of the ground, on the vertical acceleration of the ground face, on overcoming the friction of the ground on the fascia, to overcome the friction of the ground on the lower plane. Energy costs to overcome the friction of the ground on the surface of the bottom knife are zero, as the soil flies over it. The total energy costs of the bottom knife interact with the soil of one cubic meter. The horizontal long-lived force needed to move the bottom knife has been determined.
Conclusion. As a result of the calculations: the energy needed to cut the ground with the bottom knives, about 5 kJ/cube m., horizontal longitudinal force needed to move the lower knife - 16 N. To determine the total energy costs of moving the boiler unit to remove the top layer of soil from the underlying layer of the road, you need to analyze the interaction with the soil of other elements of the bucket.

Introduction. The study presents the results of the calculation of greenhouse gas emissions and polluting solids by vehicles fleet on the basis of three independent estimates of the set of initial data on the breakdown of the fleet by technological classes (the number and types of vehicles of different ecological classes, annual mileage, etc.). Such data is not provided in the forms of state statistical reports and is generated by the researchers. The article solves the problem of determining their significance for calculating the total emissions in the context of a large data array for the territory of Russia.
Materials and methods. Three different versions to the calculation of greenhouse gas emissions (basic version, equalization of transport work and new approach - equalization of fuel consumption) are proposed in order to identify differences in the obtained emissions in different conditions (i.e., to determine quantitative characteristics of the accuracy of the final values). A new method has been developed for assessing the effect of average mileage and vehicle distribution on classes on the total emissions values, implemented within each proposed version. In addition, two types of sensitivity formulas are formed by the authors to assess the impact of vehicle distribution on classes and average mileage to final emission calculations. The use of these formulas provides scientific analysis and interpretation of the influence of the factors in expert review on the final values of the emissions of each type.

Results. The differences in sorting cars into classes in expert evaluations were revealed and the closest ones are determined. It was found that the most sensitive to changes in mileage and class of cars, on which fuel consumption depends, are CO₂ emissions.
Conclusion. The scientific sensitivity analysis of both types showed the importance of maintaining the principles underlying expert evaluation from year to year in order to ensure that the results obtained are consistent.

Introduction. Most of the researchers dealing with the use of ash and slag materials (especially in the construction) have focused on the study of their mechanical characteristics or assessment of their impact on the environment. At the same time, the design of roads with embankments of soil materials in the Northern regions requires taking into account the behavior of materials in cold climates.
Although ash and slag materials are a typical dispersed soil, it is prone to frost heaving (due to the peculiarities of the internal structure). In addition, these materials have not been sufficiently tested in the development of the Russian Federation standards and codes for road design. Therefore, the professional environment is developing a hypothesis about the inadmissibility of using ash and slag materials in road embankments due to excessive frost heaving of this material, which, in our opinion, is not the case.
Methods of research. To obtain real values of ash and slag frost heaving, specialists of Siberian State Transport University carried out additional studies to determine the relative deformations of frost heaving of medium-grained samples and coarse-grained ash slabs. SibADI specialists compared the results obtained with earlier studies to determine the relative deformations of frost heaving of fine-grained ash slabs samples, and analyzed the entire array of data obtained.
Results. As a result of joint work, an empirical model was obtained that makes it possible to predict the amount of frost heaving of ash and slag material depending on its degree of compaction, initial moisture content (when working in a closed circuit or moisture in freezing through an open system), particle size distribution and freezing temperature. This makes it possible to determine the degree of frost heaving of ash and slag systems based on the grain size composition and the calculated characteristics of the subgrade.

Introduction. The calculation of structures by the semi-probability method of limit states does not answer the question how reliable the construction is. Probabilistic methods are still imperfect, and attempts to use them to evaluate structures reliability calculated with limit states sometimes lead to contradictory results. A possible reason for this is the lack of research on the influence of the asymmetry of variable distribution functions on the theoretical reliability of structures. The purpose of the research is to develop a practical method for calculating the reliability of structures with considering the asymmetry of the functions distribution and to test the method for evaluating the reliability of bent reinforced concrete elements.
Materials and methods. The reliability of structures is estimated by the variability of the strength reserve function based on the methods of moments and design points. A method is proposed for approximating the reliability of fairly complex compositions of random variables using statistical parameters (expectation, standard deviation, and skewness coefficient) of two-element functions approximated by a lognormal three-parameter distribution.
Conclusions. Considering the coefficient of the values system asymmetry in the probability calculation allows to justify the reliability of the bent reinforced concrete element designed according to the limit states. On the example of the calculation with the proposed method shown that the availability of the calculation values of the bearing strength of the reinforce concrete element in normal cross section is equal despite the values of the forces in the pressed reinforce concrete or positive reinforcement are indicated. If there is a positive asymmetry, the calculation results using the normal distribution may be significantly underestimated. It is concluded that the value of the asymmetry coefficient of the system of variables can be a justification for the use of normal or lognormal distribution for evaluating the reliability of structures. Ignoring the asymmetry of variables in probabilistic calculations can significantly distort the assessment of the reliability of structures.