As the railway lifespan is the main criterion for selection of the aggregate for ballast and for planning the maintenance of the railroad, it is important to define the relationship between the particle load resistant characteristics and a lifetime of ballast in structure. Assessment of the quality of the ballast aggregate particles under dynamic and static loading reflect both, the toughness and hardness, and these are identified with the Los Angeles Abrasion and Micro-Deval Abrasion values. The model formerly developed by Canadian Pacific Railroads was adapted to predict possible loads expressed in cumulated tonnes. Different ballast aggregate mixtures were tested in the laboratory including dolomite and granite. Calculated potential gross tonnage (expressed in Million Gross Tonnes) of the railway per lifetime for each different aggregate type presented. The outcome of this research is established classification system of railway ballast aggregate and defined Los Angeles Abrasion and Micro-Deval Abrasion values of aggregate dependently on required lifetime.

Under high cyclic loading of trains the particles of railway ballast disintegrate and worsen in a progressing way. Disintegration of ballast particles is always related to railway track deformations which require expensive continuous maintenance of railway track-the failed ballast is replaced by a new one and is later compacted (tampered). Railway ballast has a significant influence on the quality and strength of railway track. Therefore, it has been subjected to many specific requirements. Some of them are very important both in structural and cost-efficiency point of view, others are less important or already fully implemented (adapted). The scientists analyse and present research results comprising not only the entire railway transport system but also each of its components. Seeking to rationally plan further comprehensive research on the ballast bed and materials used in it, the article overviews and systematically discusses the arising problems associated with construction and aggregates of the ballast bed. The article gives the analysis of the functions of crushed rock ballast bed and requirements set to it. Also, studies the results of worldwide scientific researches and need for their adaption to Lithuanian operating conditions. The article presents the research on the condition of railway ballast layers (1514 km) in the railway lines of Lithuania and discusses the results. Additionally the detailed geological studies were carried out in 84 km in length of ballast bed.

The increased use of geosynthetics in road constructions has resulted in a need to better understanding of geosynthetics properties for the use in design and quality control. For this purpose, the regulations for use of geosynthetics for road embankments and subgrades were created in Lithuania. It was found that other European countries such as Germany and United Kingdom use not only harmonised European standards, but also has their own regulations for geosynthetics. This study indicates the relationship between regulations in Lithuania and other countries. Calculation conception and regulations for controlling characteristics were introduced first time in Lithuanian road construction market. The use of those regulations will increase the quality of construction and life time of road pavement structures.

Slab track is one of the technical possibilities to achieve the following goals: increase the conductivity of a railway, increase the highest permitted train speed, reduce the cost of railway maintenance, and increase the railway lifetime. However, the abundance of slab road constructions that occurred during the development stages presents a challenge to railway operators, designers and researchers, about the selection of a right slab track and establishing requirements to it. The present article analyses the ballastless track constructions that are used in the European Union and other world countries. The market is analysed, and a comparative evaluation of the ballastless track construction is carried out, based on the quality and price, by rating and providing the evaluation of usability and recommendations.

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