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This paper presents the testing methodology of specimens made of layers of titanium alloy Ti6Al4V in dynamic impact loading conditions. Tests were carried out using a drop-weight impact tower. The test methodology allowed us to record parameters as displacement or force. Based on recorded data, force and absorbed energy curves during plastic deformation and sheet perforation were created. The characteristics of the fractures were also analyzed. The impact test simulation was carried out in the ABAQUS/Explicit environment. Results for one, two, and three layers of titanium alloy were compared. The increase in force required to initialize the damage and the absorbed energy during plastic deformation can be observed with an increase in the number of layers. The increase in absorbed energy is close to linear. In the simulation process, parameters such as Huber–Mises–Hencky stress value, equivalent plastic strain, temperature increase, and stress triaxiality were analyzed.

This study is an attempt to investigate possible applications of rubber granulate SBR (styrene-butadiene rubber) produced from recycled waste tires as an elastic cover for prototype rail dampers, which are aimed at reducing the level of railway noise emitted in the environment. The authors present laboratory procedures and discuss the results of several experimental tests performed on seven different SBR materials with the following densities: 1100, 1050, 1000, 850, 750, 700 and 650 kg/m3. It is proven that rubber granulate SBR produced from recycled waste tires, can be used as an elastic cover in steel inserts in rail dampers, provided that the material density is not lower than 1000 kg/m3. In the conducted tests, samples of the materials with high densities exhibited good static and dynamic elastic characteristics and had sufficient operational durability.

The present paper is aimed at the analysis of under ballast mats (UBM) which are used in ballasted track structures as vibration isolators and to protect the ballast layer against fast degradation. The mats were tested in the laboratory and afterwards a novel 4-DoF mechanical model of the track structure with UBM was developed. The novelty of this study consists in the comparison of two testing procedures: a procedure based on the popular German standard DIN 45673-5 and a new European standard EN 17282, released in October 2020. Major discrepancies were demonstrated in the determined values of the static and dynamic characteristics using both approaches—especially in reference to the mats with higher stiffness.

The present paper is dedicated to the analysis of under sleeper pads (USP), which are resilient elements used in ballasted track systems as vibration isolators. Four types of USP are considered. The authors present the results of laboratory tests, which are then used as input values for the finite element (FE) and mechanical model of the structure. A special focus is put on the description of an original four-degree-of-freedom (4DoF) mechanical model of the system that includes a fractional rheological model of USP. Using the proposed approaches, the dynamic characteristics of under sleeper pads are determined, and conclusions on vibration isolation effectiveness are drawn.

The paper presents an overview of vibroacoustic isolators used in railway tracks to reduce negative effects from railway traffic. These include single components or their assemblies, with different material characteristics and location in the track structure due to track structure type (ballasted or ballastless track system). The reduction of negative effects relates mainly to the reduction of vibration and structure-borne noise. The practical solutions for railway structures include various components that perform different functions at the same time: vibroacoustic isolation and mechanical function to ensure safe and durable use of rail track (i.e. rail fastening systems, rail supporting structures). The main goals of this paper are systematization and description of basic material characteristics of vibroacoustic isolators applied sufficiently close to the place of vibration generation during the movement of rail vehicles.

The paper presents selected theoretical aspects concerning viscoelastic dynamic modelling of resilient elements used in railway tracks. In order to characterize the research methodology for resilient mats in railway tracks, German Standards [1-4] are used herein. The main goal of the paper is to demonstrate the procedure of insertion loss calculation for a single degree of freedom truck system containing under-ballast mats. Selected results of certain dynamic characteristics of resilient truck systems (transmissibility, Bode and Nyquist plots etc.) are also discussed. The results of calculations visualized in graphs, were obtained by using own applications written in programming language MATLAB.

Pedestrian fatality rate in Poland of 30 deaths per year per million population was the second highest among the EU countries in 2013. In the years 2007-2013 some 13% of pedestrian fatalities and 26% of injuries occurred at unsignalized pedestrian crossings where pedestrians should theoretically be safe. The paper presents results of research project MOBIS which was aimed to develop surrogate safety measures based on detection of dangerous situations or near-accidents. Within the project, pedestrian and vehicle traffic was recorded at four pedestrian crossings in Warsaw and Wrocław, for a period of approximately 2 months per crossing. Motion trajectories of vehicles and pedestrians were determined and certain parameters describing the pedestrian-vehicle encounters calculated. The average number of such encounters was over 1000 per day in both Warsaw and Wrocław. Dedicated video and data analysis algorithms were used to extract interactions that met certain criteria. To this end the following parameters were used: velocity profiles of pedestrians and vehicles, minimum distance between the participants, deceleration during braking, etc. These variables were used to develop surrogate safety indicators for pedestrian-vehicle encounters. A classification of encounters based on the characteristics of pedestrian-vehicle interaction is also proposed. Within the project certain solutions for increasing pedestrian safety at road crossings were installed and evaluated. These included speed cushions and flashing lights warning the drivers about pedestrian presence that were either mounted on traffic poles or embedded in the road surface. The evaluation of these solutions will be based on surrogate safety measures developed in the MOBIS project.