Stress waves propagate in soil in case of earthquake and man-made effects (traffic flow, buried explosions, shield-driven pipes and tunnels, etc.). The wave point-sources are those located at the distances equal to more than two waves lengths, which significantly simplifies solving of a problem of these waves’ strength evaluation. Distribution of stress and displacement by the stress waves propagation in elastic medium is a complex pattern. The stress distribution in propagating waves depends on the type and form of source, conditions of the source contact with medium, and properties of mediums in the vicinity of the source. The point-sources and their combinations are selected in such a way to model an influence of machines and processes on soil body in case of shield-driven pipes (tunnels).

The paper suggests application of an experimental method for the assessment of the dynamic effect of a locomotive underframe on the railway track. The assessment is to be based on spectral analysis of the response of structural elements of the railway track undergoing a shock pulse. Application of digital measuring systems for monitoring of motion of the train is also proposed.

It is necessary to make link mechanisms calculation to the strength at designing of flat link mechanisms of high class after definition of block diagrams and link linear sizes i.e. it is rationally to choose their forms and to determine the section sizes. The algorithm of the definition of dimension of link mechanism lengths of high classes (MHC) and their metric parameters at successive approach is offered in this work.

Shock absorbers are intended for developing forces providing the elimination or reduction of the amplitude of cars or their parts fluctuations. On the CIS railroads, the wedge-type shock absorber became the most widespread in trucks of freight cars. In friction shock absorbers, the friction force arises in vertical and horizontal movements of the absorber wedges rubbing on friction plates fixed on the columns of the truck sidewalls. In the article, the modeling of dynamic characteristics of a freight car with the optimized parameters of the wedge-type shock absorber is performed. The modeling is performed by means of the software complex for studying the problems of dynamics of rail vehicles: "The universal mechanism". A dynamic and block diagram of the dynamic model of the car platform, as well as of the mathematical model for studying the friction force and interaction of contact power elements, accounting the creep forces in contact by means of the FASTSIM algorithm based on the Kalker linear theory, is developed. The obtained results of modeling of an eight-wheel freight car with modernized frictional wedges show that in the truck modernization it is expedient to provide additional devices, for example a frictional shock absorber in the central step of suspension. The results of the carried out study prove the expediency of using for the upgraded truck of 18-100 model the design of M1816.06.000 SB, M1819.00.000 SB wedges, at this it is recommended to accept rigidity of elastic elements of these wedges equal to 1.1 kN/mm that is a compromise solution for the safe car movement in the empty and loaded modes.

This article aims to study experimentally the dynamic properties and traffic safety actions for gondola cars with bogies with diagonal links, operated on the territory of the Republic of Kazakhstan. The main results obtained during tests of gondola cars on bogie with diagonal links when they move along straight and curved sections as well as on switches are presented. The estimation of: dynamics coefficients, stability margin coefficients against derailment, lateral forces transmitted from the wheel to the rail, ratio of frame forces to a static load from the wheelset on the rails, and accelerations are made. The paper analyses the simulation of a polymer layer of rubber vibration absorber, to be installed between the rubbing surfaces, such as the link side of frame axle unit, and host unit is open-bearing, with lateral support of the three-piece freight car bogies, operating on the territory of the Commonwealth of Independent States. The model developed in this article consists of a rheological model of a Maxwell cell, a Fancher spring and an element which has the function of non-linearity. The simulation model can be used to study the characteristics of vibration dampers, gaskets and other power elements that have polymer properties and are installed at other types of transport and not only.