Self-propelled vibratory plate compactors are surface compaction machines with a flat operating device, which is introduced into a state of oscillatory movements and causes the movement of the machine itself along the soil surface. Industrially produced plate compactors differ significantly in technical specifications, which causes differences in the effectiveness of their use on different types of soil and under various conditions. This fact sufficiently complicates both the design of new models of vibratory plate compactors and the selection of suitable models for soil compaction under various conditions. A significant part of manufacturers provides limited recommendations of the technological capabilities of various models of vibratory plate compactors which increases the risk of insufficient soil compaction and a decrease in the service life of structures built on it. The purpose of the study was to collect data on industrially produced models of vibratory plate compactors, as well as to analyze manufacturers recommendations for the use of vibratory plate compactors in various conditions. The collected data allows us to evaluate the gathered experience in the development and improvement of model lines of vibratory plate compactors and can be used when designing new models of vibratory plate compactors.

In the course of the study, an improved model of the motion of a viscous lubricant in the working clearance of a radial plain bearing with a modified support profile was developed. The main attention was paid to the effect of a polymer coating with a groove on the distribution of pressure and velocity of the lubricant. To achieve the stated goals, numerical analysis methods were used, which provided the creation of a detailed picture of the distribution of pressure and velocity inside the working zone. Particular emphasis was placed on taking into account the compressibility of the lubricant, which made it possible to significantly improve the accuracy of calculations and increase the reliability of the obtained data. The model proved to be reliable and accurate, which is confirmed by the consistency of the calculated data with experimental measurements. As a result of the modeling, the characteristics of the distribution of pressure and velocity of the lubricant in the system were studied in detail. The study showed that the introduction of a polymer coating with a groove significantly affects the behavior of the lubricant, improving its distribution and reducing potential zones of overheating and wear. Thus, this work is an attempt to make a contribution to the field of radial plain bearing research. The results obtained can be used for further improvement of bearing designs, which will increase their reliability and durability in various industries.

An increase in the quality of unloading of hard-to-bulk materials from stationary and mobile bunker tanks can be achieved by using selective mechanical arch breakers. The configuration of the working bodies of these devices will ensure the stable production of a wide range of materials with different physical and mechanical properties from bunkers with different geometries. Using a theoretical tool that has found application in the research of metal and soil cutting processes, a theoretical description of the effect of the working bod¬ies of a portable arch breaker on the packed material in the hopper was given. Having studied the nature of the device’s operation directly in the cavity of the hopper outlet funnel (rotation of the working bodies with their one-time deviation at various stages of unloading the material), expressions were obtained to determine the operating loads and the power consumed. At the same time, in the obtained formulas, along with the physico-mechanical properties of the discharged materials, the design and operating parameters of the device were taken into account. Using the obtained expressions, the construction of theoretical dependencies is carried out, establishing the influence of several variable design-mode parameters (dimensions of working bodies, their feed, angular velocity) on the power consumed. The results of the conducted research can be used to optimize the structural and operating parameters of vaulting structures in the design of their laboratory and industrial samples.

The article considers the problem of embedding a rigid body into an isotropic elastic-elastic half-space through a deformable plate having properties characteristic of thin plates – elastic bodies with a thickness much smaller than other geometric dimensions and studied according to the theories of Kirchhoff and Poisson. The presence of a thin plate changes the characteristics of the embedding process, since the methods applicable to solving direct indentation into the half-space cannot be used to determine the dependence of the load on deformation. The integral differential equations determining the embedding of a rigid body of finite dimensions are solved using the discretization approach. The integral transformation method made it possible to determine the loading operator, an integral part of which is the parameter of the relative stiffness of a system consisting of a plate and an elastic half-space. The relative stiffness depends on the elastic modulus and geometric parameters of the contact area and the elastic plate. The influence of the stiffness of an elastic plate on the relative stiffness of the entire system is analyzed and the results demonstrating the effect of plate stiffness on the Boussinesq problem of deformation of a half-space are presented. The solution of this problem is applicable to the practical field of scientific research on the compaction of asphalt concrete mixtures with various types of sealing working bodies, since the nature of the formation of defects in asphalt concrete coating retains scientific interest in the creation of alternative sealing equipment.

The emergency brake is an essential element of the escalator safety system, designed to prevent the negative consequences of emergency situations. However, due to the very rare operation of this mechanism, the effect of dynamic loads on its elements has not been sufficiently studied. In addition, the use of normally closed brakes with a constant torque requires a more detailed study of the setting of the contacting surfaces. The purpose of this work is to evaluate the operating parameters, as well as the stress-strain state of the emergency brake elements using virtual modeling in the Comsol Mutliphysics software package, under conditions of different loading of the escalator and the area of setting of the friction surfaces. The article presents the results of numerical simulation of the dynamic loading mode of the clutch bolts of the ratchet emergency brake device of the tunnel escalator. The case of the occurrence of an abnormal node position as a result of the formation of a grip on the working surfaces of the friction device is considered. The results of a numerical experiment performed in the program of finite element modeling of Comsol Multiphysics in a three-dimensional nonstationary formulation are presented.

Single-span mobile ropeways on the basis of two airmobile rope units connected by a single carrying-traction rope system currently represent the newest type of aerial ropeways designed for pre-property use in difficult natural conditions in the absence of the necessary ground transport infrastructure. The article considers the problem of developing a complex mathematical model of a single-span mobile pendulum-type ropeway based on airmobile rope units, which can be considered as a basis for further research on the creation of an integral scientifically based theory of this type of transporting equipment. The methodological principles of creating the specified mathematical model are formu-lated, its structure is proposed and a brief description of the internal subsystems of the model is given.

The internal combustion engine operates in unsteady modes for a significant part of the time when the vehicles is moving. This is unavoidable for vehicles with traditional power plants for the following reasons: 1) the need to regulate the power on the driving wheels, 2) the effective performance and environmental qualities of the engine in unsteady modes are often worse in relation to those in steady-state modes of operation; this is due to the influence of many factors and has been studied in many well-known scientific papers. Experimental studies of current fuel consumption, effective torque and environmental qualities of the engine at unsteady speeds are relevant. This is due to the complexity of the processes that take place in the units. Their main goal of these studies is to ensure greater adaptability of the internal combustion engine and power plant to work in unsteady modes. The methodology for determining the current fuel consumption when operating in an unsteady mode of an automobile internal combustion engine with external mixing and a dead-end fuel ramp with distributed gasoline injection through electromechanical injectors is improved in this article. An experimental study was carried out in the work. The injectors of the Denso 23209-39295 model of the 2ZR-FXE engine of the Toy-ota Prius PHV 4th generation vehicles is selected as an example. The fuel pressure drop, the duration of the electric control pulse and the magnitude of the electric voltage are considered as parameters that affect the volumetric performance of the injectors. The Autool ST160 stand and additional electronic equipment devel-oped by the authors were used in the study. The result of the study is an analytical device for more accurate determination of the current fuel consumption in unsteady engine operating modes. The improved technique does not require the installation of additional sensors and equipment on the vehicles.