The analysis of domestic and foreign studies in the field of evaluating the dynamic strain of passenger car bodies allowed us to find out that most of the methods are based on the evaluation of the vibration strain. An improved method is proposed to consider to evaluate the vibration strain of the car. As a method for determining the body's structural properties, a mathematical modeling method is proposed. On the basis of this method, a finite element model of the body is developed, which natural frequencies and forms of vibrations are calculated by Lanczos method. The results obtained by finite element model are compared with the data obtained during tests conducted by the Testing Center TIV. The discrepancy between the calculation and the experiment is 11.85%, which indicates the adequacy of the created finite element model. To define the dynamic load of the body the developed finite element model was reduced to four variants, each of which is transformed into a spatial hybrid dynamic model. The results obtained during the calculation are compared with the values of the running tests of the car. The analysis of the data shows that the fourth variant of the finite element model of the passenger car body, which takes into account the real distribution of the mass of the internal equipment elements and the interior has values more approximate to the data obtained during running tests. Based on this, it can be concluded that this option is most suitable for calculating the stiffness characteristics of the passenger car body.

Domestic and international experience in increasing the bearing structure rigidity of vehicle bodies in the form of a reinforced shell with a cut-out is analyzed. Based on the analysis, approaches related to the reinforcement of the car underframe with additional longitudinal elements and bearing partitions are considered as promising. Options for installing one as well as with two partitions connected by longitudinal elements are considered. The first frequency of the body bending vibrations, the maximum stresses acting in the reinforced part of the structure, as well as the amount of mass gain associated with reinforcements are accepted as the criteria for choosing a rational design to increase the rigidity of the body bearing structure. The study object is the bearing structure of the sleeping passenger car body, 61-4517 model, produced by Tver Car Building Plant. Having analyzed the bearing structure of the car body, four variants of reinforcing the bearing system are proposed. For each of them, from four to ten structural designs are considered, differing in the type of profiles for their formation. The efficiency analysis within the accepted criteria is carried out by computer simulations using modern industrial software systems based on the finite element method. A detailed spatial and plate body model based on finite element is developed. Heavy equipment is included as some finite elements, as well as interior designs of the passenger car. The results obtained using the developed model are verified by the data of bench full-scale tests of the passenger car body. For each variant and design, the values of the first natural frequency of the body bending vibrations, maximum stresses arising in the structure under the action of regulatory forces, as well as the value of the mass gain of the bearing structure are obtained. The analysis of the obtained variants made it possible to find out the rational variant and its design, which provides an increase in the rigidity of the body bearing structure, a reduction in operating stresses with a minimal increase in the mass of the metal structure.

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The purpose of the work is to increase comfort and safety of railway passenger transportation, at the expense of passenger car body vibration load decrease. The analysis of the investigations carried out and dedicated to the definition of rigidity property impact upon the level of passenger comfort and traffic safety has shown that the first mode of vertical bending impacts considerably upon car body dynamic behavior. The analysis of vibration load impact upon passenger car body was carried out in accordance with Dumitriu’s technique. As apposed to the investigations carried out earlier in the paper the data on car metal structure acceleration are obtained through the methods of mathematical modeling based on solid and finite element models. On the basis of the data obtained and natural running tests there was created and verified a particularized lamellar finite-element model of a car body with the aid of which there were obtained values of vertical and horizontal accelerations of a car body metal structure. The analysis of the results obtained has shown that within the frequency range of 8.9. – 20 Hz there are observed acceleration surges which are among the most sensitive ones in terms of the impact upon man and transport comfort support. At the frequencies obtained there was carried out a passenger comfort investigation with the aid of which it was defined that at the frequency of car body own bending oscillations of 8.9 Hz – a comfort index is above 4 units that shows a low comfort level. A frequency of 8.9 Hz corresponds to a vertical bending mode which is the most significant mode of car body deformation in terms of passenger comfort support. With regard to this in the works there was offered a number of efficient measures for strengthening car body structure bearing capacity with the goal of its bending rigidity increase which provides an installation of a supplementary bearing partition in the mid-section of a car body, and also the introduction of auxiliary longitudinal elements in a frame supporting design. For the effectiveness assessment of measures offered there was carried out re-investigation according to the technique described. As a result of the computation it was defined that the design measures offered allowed increasing a frequency value of own bending vibration of car body metal structure up to 11.7 Hz. The analysis of the results obtained allowed drawing a conclusion of the effectiveness of design solutions offered on car body vibration load decrease.

The article discusses the possibility of using the object model for constructive solutions of devices to increase the tractive qualities of locomotives. The proposed approach has been tested on the example of creating a device to improve the traction qualities of a locomotive by applying a magnetic field to the wheel-rail contact zone. The use of the proposed device will reduce losses associated with eddy currents induced by a magnetic field in the wheels and rail, as well as reduce the probability