• Journal of the Korean Society for Railway
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• v.18 no.2
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• pp.117-126
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• 2015

The development of railway roadbed for 600km/h train speed level is very difficult because unpredictable static and dynamic interaction occurs between the ultra-high speed train and the infrastructure. Especially, an earthwork-bridge transition zone is a section in which influential factors react, such as bearing capacity, compression, settlement, drainage, and track irregularity; these interactions can include complicated dynamic interaction. Therefore, if static and dynamic stability are secured in transition zones, it is possible to develop roadbeds for ultra-high speed railways. In the present paper, design parameters for transition reinforcement applied to present railway design criteria are analytically examined for ultra-high speed usage on a preferential basis. Design parameters are the presence of reinforcing materials, geometric shape, stiffness of materials, and so on. Analysis is focused on the deformation response of the track and running stability at ultra-high speed.

• Journal of Korean Society of Transportation
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• v.28 no.2
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• pp.171-181
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• 2010

The integrated transit fare system of Seoul metropolitan area has given positively evaluated with reduction of user cost and activating the transfer behavior from its opening year, July 2007. However, there were only few research about railway demand forecasting methodology, especially mode share, has conducted under the integrated fare system. This study focuses on the utility estimation by each mode under the integrated fare system, and on the coefficient actualization relates on travel time and travel cost estimation with Household Travel Survey Data 2006. Also the railway demand analysis methodology under various fare systems is presented. The methodology from this study is expected to improve accuracy and usefulness in railway demand analysis.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.9
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• pp.1-8
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• 2020

The Ministry of Land, Infrastructure and Transport of Korea has been trying to spread integrated railway communication network technologies based on a major railway policy since 2012. As a result, the world's first commercial Long-Term Evolution - Railway (LTE-R) network was established on the Gangneung line (Manjong station - Gangneung station) and has been commercially operating as a railway communication system since 2017. Special function and performance requirements are needed for safe and efficient railway operations, such as group calls, emergency calls, functional addressing, and train control based on wireless communications. In this paper, we present functional and performance railway communications requirements that are based on European wireless railway communications systems. In addition, we measured communications characteristics and performance using a KTX field test on the Gangneung line to analyze the validity and reliability of the LTE-R network. Although the average Radio Frequency (RF) conditions were satisfied in the requirements, we found sudden communications quality degradation, such as Radio Link Failure (RLF) in some railway sections. We propose a way to improve performance and network installations based on in-depth analysis of LTE-R communications field-test results.

• Wind and Structures
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• v.35 no.6
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• pp.405-418
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• 2022

The aerodynamic behaviour of a CRH high-speed train under three infrastructure scenarios (flat ground, embankment, and viaduct) in the presence of a crosswind was simulated using a 1/8th scaled train model with three cars and the IDDES framework. The time-averaged and instantaneous flow field around the model were examined. The employed numerical algorithm was verified through a wind tunnel test, and the grid and timestep resolution analyses were conducted to ensure the reliability of the data. It was noted that the flow around the rail line was different under different infrastructure scenarios, especially in the case of the embankment, which degraded the aerodynamic performance of the train under the crosswind. The flow around the train on the flat ground and viaduct was different, although the aerodynamic performance of the train was similar in both cases. Moreover, the viaduct accidents were noted to have the most critical consequences, thereby requiring the most attention. The aerodynamic performance of the train on the windward track of the embankment under the crosswind was worse than that of the train on the leeward track. But for the other two infrastructure scenarios, the aerodynamic performance of the train on the windward track is relatively dangerous, which is mainly caused by the head car. These observations suggest that the aerodynamic behaviour of the train on an embankment under a crosswind must be carefully considered and that certain wind protection measures must be adopted around rail lines in windy areas.

• Journal of the Korean Geosynthetics Society
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• v.22 no.1
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• pp.97-107
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• 2023

This study analyzed the causes of frost damage and freezing depth for concrete ballast sites in the Gangwon mountainous area, which has a high freezing index, and considered the equation for freezing depth in concrete roadbeds. Comparing the freezing depth tendencies of concrete roadbeds in the Gangwon mountainous area and Gangwon area, it was found that the freezing depth of concrete roadbeds was higher than that of the Gangwon area when the freezing index was less than 400. However, in sections with a freezing index greater than 400, the freezing depth was higher in the Gangwon area than in the concrete roadbeds. This study proposed an equation for computing the freezing depth in the Gangwon area to provide basic data for establishing preventive measures against frost damage during railway and road construction projects in the Gangwon region.

• Proceedings of the KSR Conference
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• 2001.10a
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• pp.115-134
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• 2001

현재 정부는 지금까지 관청 조직인 철도청에 의해 철도시설의 건설 및 유지관리 업무와 열차 수송 업무 등 운영부문을 일괄적으로 수행되어 오던 우리나라의 철도교통체계를 근본적으로 변화시키는 작업을 추진하고 있다. '철도구조개혁'이라 지칭되는 이러한 작업은 소위 말하는 상하분리 또는 수직적 분리의 원칙에 따라 철도청의 업무를 하부구조에 해당하는 기반시설(infrastructure) 부문과 철도차량을 운행하여 여객과 화물을 운송하는 운영부문으로 구분하여, 기반시설에 해당하는 부문은 기본적으로 사회간접자본의 개념에서 국가의 책임으로 하고 운영부문에 해당하는 부문은 타 교통수단의 운영주체 위상(예: 고속버스 회사, 항공회사 등)과 같은 민간 경영체제로 전환한 다는 것이 주 내용이다.(중략)

• Proceedings of the KSR Conference
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• 2000.11a
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• pp.111-118
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• 2000

This paper proposes the track layout criterion for the LRT(light rail transit). All criterions established concerning dimension and performance of LRT vehicles that are three types. Types of vehices are AGT(automated guided train) steel wheel. AGT rubber tire and LIM(linear induction motor). Using theoritical approach, adaptation and validity of criterions are verified. Proposed criterions may provide a standard scheme for design and construction of the infrastructure on LRT.

• Proceedings of the KSR Conference
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• 2002.10b
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• pp.937-942
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• 2002

As the subway composed of rolling stock, power supply, signalling, infrastructure is complex system, the optimization through standardization is one of the most effective way to reduce the cost of construction and operation. However, the subway in Korea has been built and operated in different kinds of system. In this paper, review for standardization of urban transit in Korea is executed and presented direction to standardization.

• Proceedings of the KSR Conference
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• 2004.10a
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• pp.1634-1645
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• 2004

This study reveals that rail reform which separates infrastructure from train operation requires more safety activities to train operator than before. To meet these requirements the train operator, KNR, should build up more expertness, accept accidents investigation by the third party, establish and operate safety knowledge management system, and manage a forum which facilitates the communication between the parties concerned.

• Proceedings of the KSR Conference
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• 2005.11a
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• pp.569-574
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• 2005

In this study, test standards were developed for performance verification of the high speed(350km/h) rolling-stock. The performance test system consist of three type tests; the component test for core item, the completed car test for combined function & operation and the trial driving test for compatibility & interrelationship with infrastructure.