Development of railway infrastructure at the turn of the 20th and 21st centuries, as well as the speeds of trains in passenger and freight traffic are the result of improving the structure of modern rail vehicles and railway infrastructure optimization. The structure of the railway surface, which enables high speeds and transferring ever greater loads and pressures of up to 25–30 t/vehicle axis, must meet very strict strength and durability requirements. This paper discusses mathematical and numerical tools used in simulation and experimental tests of railway surfaces, as well as its selected elements. Issues addressed in this paper concern, among others, modeling of the railway track, calculations related to its static and dynamic loading, and simulation of the technological process of selected elements of railway turnout. Selected results of the simulation tests on numerical models showing their behavior under different loads are also presented in this paper. The concept of symmetry is included in the possibility of applying the method described in the article both for testing other sections of railway lines, as well as for testing other elements in which stresses occur.

The effectiveness of railway brakes strongly depends on their thermal condition. A computer simulation and experimental investigations on a full-scale dynamometric stand were chosen as an adequate analysis of the heat transfer process in brakes. The article introduces a two-dimensional, axisymmetric numerical model of the tested disc brake. Boundary conditions related to the heat generated in the friction brake and heat transferred to the environment are also presented. The transient heat transfer problem was solved using the in-house computer program of the finite element method. The article presents simulations and experimental investigations of the intensive braking of a train with an initial high speed. Temperature responses of the disc brake on the friction surface and at other selected points are shown. In addition, a thermal imaging camera was used to assess the temperature distribution on the friction surface of the disc. The results of experimental and simulation tests were preliminarily compared. Similar maximum temperature values were obtained at the end of braking with a particular discrepancy in temperature responses during the analyzed process.

Efficient transport solutions are based on multimodal systems, with the dominant role of rail and road transport in land versions of the systems and the connecting and directing part of intermodal terminals, transhipment terminals or warehouse centres. The implementation of transport processes is always associated with the risk of lack of timeliness (quality) or threats to people, equipment and cargo (safety) resulting from human, technical, organizational and global factors like pandemics or war. The article contains a risk mapping method in multimodal transport systems configured to estimate the risk of lowering the quality of logistics services (on-time deliveries, etc.). The method combines factors usually considered separately in studies on individual modes of transport. A formal notation of risk factors as a mathematical model was proposed, and a case study was provided to picture the implementation.

The correct operation of the continuous welded track requires diagnosing its condition and preparation of track metrics requiring measurements of displacements of rail under operation. This is required as there are additional thermal stresses in the rails with values depending on the temperature changes of the rails. Therefore, the climatic conditions are important. This paper presents the original effective analytical method for diagnosing the condition of continuous welded track based on experimental research. The method allows for an appropriate repair or maintenance recommendation. In the experimental research, the authors considered track diagnostic conditions for two conditions: track under load and track without load. This paper presents empirical formulas for calculating rail temperature and longitudinal force based on ambient temperature, developed from long-term measurements. The formulas were developed for a track located on a straight section—both for a rail loaded and unloaded with a passing train under the following conditions: 60E1 rail, not on an engineering structure, conventional surface, wooden sleepers and very high train traffic load. The obtained results in the value of the correlation coefficient R² ≥ 0.995 attest to very high accuracy of the calculations performed with the method proposed by the authors.

In Poland, due to the increase in investments made by railways in recent years, and thus the increase in the replacement value of transport infrastructure, the need for expenditure on infrastructure maintenance will increase in the next 30 years, or the development of the developed transport network will degrade. As part of the overall discipline of resource management, subdiscipline has emerged - infrastructure asset management. As part of the management of railway transport infrastructure, the demand for cheaper maintenance costs will grow. The cost reduction of infrastructure maintenance is possible through meticulous assessment of its condition, rational selection of locations and scope of repairs at the assumed risk level, as well as at the stage of preparation of new construction or modernization projects taking into account aspects of later maintenance. For some time, we have been observing the accumulation of knowledge (methods, programs, procedures) in the country and abroad enabling optimization of infrastructure condition assessment and programming of its maintenance. The implementation of these solutions may result in a more rational use of funds for infrastructure maintenance and not disturb its smooth functioning in operation. The article discusses aspects that should be considered in the design process of railway infrastructure. Particular attention was paid to the durability of steel components of the railway superstructure, maintenance costs as well as aspects related to the capacity of the track node. An example of dependence of selected values of radial arcs depending on their durability and maintenance costs was presented. It was proposed to change the track layout at the Warszawa Srodmiescie passenger stop planned for reconstruction. Calculations of kinematic parameters for various configurations of railway turnouts were performed. Also, calculations of the capacity for the existing track system solution as well as the proposed track system after reconstruction of the analysed Warszawa Srodmiescie railway station were also carried out.