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PL
Główną rolą współpracujących ze sobą warstw ziarnistych w nawierzchni kolejowej, tzn. podsypki, warstwy ochronnej i podtorza jest zapewnienie przekazywania obciążeń oraz odpowiednie podparcie rusztu torowego. Podsypka jest jednak najsłabszym elementem nawierzchni kolejowej, dlatego wymaga odpowiedniego doboru materiału, uziarnienia, wzmocnienia czy zagęszczenia. W artykule opisano stosowane rozwiązania w materiale ziarnistym podsypki tłuczniowej zwiększające trwałość zarówno samej podsypki, jak i eksploatowanej nawierzchni kolejowej. Zastosowanie elementów sprężystych wg ich sztywności rekomendowano w celu zwiększenia trwałości podsypki kolejowej na etapie projektowania, budowy i utrzymania eksploatowanych nawierzchni kolejowych. Wskazano również zalecane rozwiązania do stosowania w praktyce inżynierskiej, które można dostosować do aktualnego cyklu życia nawierzchni kolejowej.
EN
The main role of the cooperating layers in railway track structure: ballast, protective layer and subgrade is to provide load transfer and proper support of the railway track. However, the ballast is the weakest element in the ballasted railway track structure, therefore it requires the appropriate selection of material, grain size, strengthening or compaction. The used solutions in the granular material of the breakstone ballast increasing the durability of both the ballast itself and the operated railway track structure are described. The use of elastic elements according to their stiffness are recommended to increase the durability of the railway ballast at the stage of design, construction and maintenance of operated railway track structures. The recommended solutions for use in engineering practice, which can be adapted to the current cycle life of the railway track structure, are also shown.
PL
Postępująca degradacja nawierzchni kolejowej powoduje zwiększenie oddziaływań przekazywanych przez nią na podtorze, co wymaga odpowiedniego doboru materiałów, ich uziarnienia, zagęszczenia w górnej strefie podtorza. Przedstawiono analizę obciążeń powstających podczas eksploatacji nawierzchni przekazywanych na podtorze oraz materiałów przydatnych do zastosowania na warstwy ochronne. Zaproponowano możliwość wykorzystania kruszywa z recyklingu zużytej podsypki jako pełnowartościowego materiału.
EN
The progressing degradation of the railway track structure causes an increase in the impacts transferred by it on the subgrade, which requires the appropriate selection of material, their graining and compaction in the upper zone of subgrade. An analysis of the loads arising during the operation of the track structure transferred on the subgrade and the materials suitable for use in protective layers is presented. The possibility of using recycled aggregate from the used ballast as a full-value material was proposed.
EN
Ballast layer is the most weak element of railway track that causes track geometry deterioration. At the same time, it is subjected to intensive particle breakage during the corrective tamping. This causes high maintenance costs of ballasted track. The present paper is devoted to the study of tamping methods. The present machine tamping methods are considered and compared. The possible influence of the tamping technology on the ballast-related maintenance costs is analyzed. The side tamping technology is studied in detail with theoretical and experimental methods. The process of material transport during the side tamping is studied using a scale model of ballast layer and photogrammetric measurements. A theoretical finite element model (FEM) is validated to the experimental results. The study shows that the side tamping is a promising method for the development of a universal, superstructure independent tamping technology.
EN
The production of aggregates in rock mining requires an optimal system of crushers, separators and conveyors. Proper machine selection allows aggregates with appropriate technical parameters to be obtained and increases the output of the required fractions with a given unit cost. The usage of rock raw materials for the production of railway ballasts used in a railway track superstructure is connected with the necessity of meeting strictly defined quality requirements. This paper presents an example of the use of an impact crusher in a selected quarry for the purpose of obtaining the correct parameters of railway ballast and a suitable grain curve. The evaluation was carried out based on the results of technological tests which were compared with the technologies used to date, thus ensuring the effectiveness of the solution in the practice of quarries.
EN
Ballast layer has weighty share in the lifecycle costs of railway track. The strict standards and maintenance rules of ballast grading significantly contribute to the ballast costs. One ways to the costs reduction is differential demands to ballast grading for the secondary and low loaded railway lines. Additional one is the different ballast grading over the ballast height. This study presents a full scale laboratory investigation of technical efficiency of such railway ballast under the long-term cyclic loading in comparison with the standard ballast layer. The double layer is presented with standard grading ballast upper layer and bottom sub ballast layer consists of ballast mixture. Pressure distribution under the ballast layer and permanent settlements of the layers are measured during the loading cycles. The reference measurements with standard grading ballast material are carried out. The study shows that initial settlement accumulation of the double layer railway ballast are lower to that of the standard ballast layer. However, the settlements accumulation intensity of the ballast is higher. The analysis of the pressure distribution measurements under the ballast layer and the settlements inside the ballast layer explain the causes of the different settlement accumulation.
6
Content available Stress-dilatancy relationship for railway balast
EN
Knowledge of the mechanical behaviour of ballast is very important for designing a railway track, especially for high-speed lines. The monotonic drained triaxial tests of scaled and fouled ballast presented in literature were analysed using the Frictional State Theory. The stress-plastic dilatancy relationship shows that four characteristic stages of shearing may be specified. The influence of stress level and water content may be quantified by the use of the Frictional State Theory.
PL
Podczas eksploatacji nawierzchni kolejowej często dochodzi do niepożądanego przemieszczania lub obsuwania się tłucznia. Zjawisko to najczęściej występuje w strefie przejściowej między nasypem wykonanym z tłucznia a sztywnym podłożem, np. bezpośrednio przed mostami i wiaduktami, w strefie przejazdów kolejowych i przy przejściach przez tory, a także na szczególnie obciążanych łukach torów oraz w okolicy zwrotnic i krzyżownic.
EN
The mechanical characteristics of the railway superstructure are related to the properties of the ballast, and especially to the particle size distribution of its grains. Under the constant stress-strain of carriages, the ballast can deteriorate over time, and consequently it should properly be monitored for safety reasons. The equipment which currently monitors the railway superstructure (like the Italian diagnostic train Archimede) do not make any “quantitative” evaluation of the ballast. The aim of this paper is therefore to propose a new methodology for extracting railway ballast particle size distribution by means of the image processing technique. The procedure has been tested on a regularly operating Italian railway line and the results have been compared with those obtained from laboratory experiments, thus assessing how effective is the methodology which could potentially be implemented also in diagnostic trains in the near future.
PL
W opracowaniu zawarto wybrane zagadnienia dotyczące technologii oczyszczania podsypki. Określono rodzaje i przyczyny zanieczyszczeń podsypki. Zaprezentowano wybrane typy maszyn przeznaczonych do zmechanizowanego oczyszczania podsypki. Przedstawiono wybrane problemy związane z zanieczyszczeniem podsypki, występujące na liniach kolejowych.
EN
Study contains selected problems of the technology of ballast cleaning. Kinds and reasons of ballast contamination were described. Selected types of ballast cleaning machines were presented. Examples of problems with contaminated ballast on railway lines were presented.
10
Content available Nowe wymagania dla podsypki kolejowej
PL
W artykule porównano normy dotyczące podsypki kolejowej: dotychczas obowiązującą normę PN-B-11114:1996 z nową normą PN-EN 13450:2004. Scharakteryzowano tymczasowe warunki techniczne dla podsypki tłuczniowej naturalnej i otrzymanej z recyklingu, uwzględniające wymagania nowej normy. Podano aktualne akty normatywne, dotyczące podsypki.
EN
Two norms concerning railway ballast: PN-B-11114:1996 valid so far and the new norm PN-EN 13450:2004 are compared in the paper. Temporary technical requirements, taking into account the requirements of the new norm, for natural stone ballast as well as ballast obtained through recycling, are characterised. Valid standards concerning ballast are presented.
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