• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2003.06a
• /
• pp.1517-1520
• /
• 2003

In this paper, we design a wedge type rail-clamp which can protect container crane from wind with constant clamping force regardless of the operating period. When we design wedge type rail clamp, it is important to determine the weight for locker to descent smoothly with an initial clamping force of rail and pad. Therefor, this paper suggest a process to decide a wright within proper range which could be obtained using FEA of wedge type rail clamp.

• Proceedings of the KIEE Conference
• /
• 2007.10c
• /
• pp.214-216
• /
• 2007

With the arrival of ubiquitous networking environment, it has been needed to build up the u-infrastructure for railway, and so the realization of ubiquitous rail system could be preferred. We have studied the direction for development of technology for realizing u-rail system through the analysis of the condition and demand on railway system, and investigated the requirements, level of technology and applicability of information infrastructure for realizing u-Rail. And also analyzed the technology based on railway information to determine the role of existing information system and connect it, which is adequate for u-Rail and the project selection.

• Journal of Power System Engineering
• /
• v.13 no.6
• /
• pp.117-122
• /
• 2009

The wedge type rail clamp compresses the rails with small clamping force at first, and with large clamping force when the wind speed increases because of the wedge working. If the supporter is not installed in the rail clamp with V-type wedge when the wind speed increases more and more, the structure will occur overload which leads the structure to fracture. But in the clamp with U-type wedge the supporter is not necessary because the tangential angle of the wedge increases as the sliding distance increases. The proper shape of U-type wedge is determined by the initial clamping force and the tangential angle of the wedge. Accordingly we, first carry out the finite element analysis in order to analyze the relation between the sliding distance and the wedge angle. Next we suggest the proper shape of U-type wedge as analyze the relation between the radius of curvature and the sliding distance.

• Proceedings of the KSR Conference
• /
• 2010.06a
• /
• pp.371-379
• /
• 2010

Since Kyoto Protocol to the United Nations Framework Convention on Climate Change in 2005 takes effect, the transportation policies of most countries move toward encouraging the use of the transit mode with energy efficient and low carbon. Korea is 8th country of producing Co2 emissions and will be one of obligation countries decreasing Co2 after year 2013. In order to improve the efficiency of national transport system investment, this study developed the strategies toward rail-oriented transport system by considering operational speed and accessability, rail-oriented development, and introduce of ubiquitous technique in railway. The four major strategies targeted for future year are introduced here such as One-hour rail(connecting major cities within one hour), Seamless 30(accessing major railway stations within 30 minutes, Rail urbanism (railway-based urban planning), and U-rail (railway service with ubiquitous technique). Each strategy includes several action plans and their priorities are investigated using AHP(Analytic Hierarchy Process) to organize them by time scheme as short, mid, and long term perspective.

• Proceedings of the KSR Conference
• /
• 2010.06a
• /
• pp.315-323
• /
• 2010

It is suggested that the service life of the continuous welded rail(CWR) is estimated by the relationship between the rail surface irregularity according to the accumulated passing tonnage and bending fatigue of welded part in CWR. In this study, it measured bending stress of rail according to the rail surface irregularity in the concrete track on the Seoul Metro. In addition, the relationship between rail surface irregularity and bending stress in concrete track is analyzed by results of the field test. Finally, this study clarified the relationship among bending stress(Y) of rail, train speed(U), rail surface irregularity(v, w) in concrete track. The result of this study is able to use the basis data to establishing the periodic replacements criterion of CWR.

• International Journal of Korean Welding Society
• /
• v.4 no.1
• /
• pp.1-9
• /
• 2004

Continuously welded tracks, first introduced on train lines, are being used increasingly in Europe. And the different arc welding methods are only used on minor lines, private tracks and in the manufacturing of switches and crossings. Mobile flash butt welding belongs the future in rail welding on side if new tracks have to be erected. The following contribution reviews the processes available, usual test methods for welded rail joints and various applications.

• International Journal of Railway
• /
• v.7 no.1
• /
• pp.1-7
• /
• 2014

Fatigue and wear in wheels is often due to the forces and loading. These certainly have fundamental effects on reducing the wheel life and increasing the costs related to repairing and maintenance. Modeling and stress analysis of a wheel sample existing in the Iranian fleet have been performed in its contact with U33 and UIC60 rails. The results have been reviewed and analyzed in elastic and elastic-plastic phase and under static (railcar weight) and quasi static loads. Moreover, effects of wheel diameter, axle load, wheel material, rail type are analyzed.

• Journal of the Korean Society for Railway
• /
• v.9 no.2 s.33
• /
• pp.212-221
• /
• 2006

This paper examines the outcomes and tasks of U rail privatization especially focusing on the rail safety. Earlier research which focused on the rail safety had little knowledge of the explanations for recent changes of safety scheme. Moreover, they had difficulty making a direct comparison of safety between national rail and the privatized rail. Therefore we are left without a good explanation which has a comprehensive perspective. I attempt to show the outcomes of safety in the rail privatization process and its tasks focusing on the recent fatal accident. This paper argues that the UK's rail safety has a framework which is too complicated with overlapping responsibilities that brought about inefficiency, increasing costs. Especially infrastructure enterprise did not come to play an appropriate role. However, after 2000, the government took charge of setting the strategy for railway safety, and the Office of Rail Regulation covered safety, performance and cost. I explain that these changes present a good opportunity to solve the problem of passing the buck for rail accident. Through the analysis, I find that outcomes of rail privatization in safety are improved comparing the national rail. However, safety performance, for example the collision of structures of cars and looseness of rail should be improved. In future, the problems of fatal accident and a bit of duplicate safe system should be addressed.

• Proceedings of the KSR Conference
• /
• 2004.06a
• /
• pp.832-836
• /
• 2004

This study was aimed to establish the acceptable contact force range between power collector and 3rd rail type conductor rail, and ramp slope for the Korean standardized rubber-tired AGT light rail vehicle. Dynamic behavior of the power collector, contact force variation and interruption in operation, were analyzed in the worst installation tolerance and various ramp slope of the conductor rail. The power collector was designed and manufactured to satisfy the Korean Standardized Specifications of the rubber-tired AGT light rail vehicle.

• Proceedings of the KSR Conference
• /
• 2001.10a
• /
• pp.534-539
• /
• 2001

This paper presents the critical speed analysis of geogrid-reinforced rail roadbeds on soft soil. A rail roadbed on soft ground must be designed to avoid intolerable stress in the underlying soil and to give sufficient support for the rail system. At high speeds, the deformation of rail systems will gain dynamic amplification, and reach excessive values as a certain speed, here termed critical speed is approached. The elastic Winkler foundation model was used to predict the critical speed of geogrid-reinforced rail roadbeds on soft soil and the model properties were determined by the in-situ cyclic plate load test. Based on the parametric study of elastic beam on Winkler foundation model, the critical speed increase with the increase of the flexural risidity of subgrade EI and the stiffness coefficient of Winkler foundation k. From the in-situ cyclic load tests and analysis of elastic beam on Winkler foundation model, the critical speed increase with increase in number of reinforced layer and non-dimensional value for depth of first geogrid layers and the thickness of reinforced rail roadbed u/d.