• Journal of the Korean Operations Research and Management Science Society
• /
• v.38 no.3
• /
• pp.23-35
• /
• 2013

It is very important that the calculation of railroad track capacity in infrastructure investment analysis and train operation planning. The dwelling time is one of the factors that influence in railroad track capacity. Current research in dwelling time has been focusing on theoretical investigation, the state of the research in effective variable (dwelling time etc) is insufficient. In this paper, we clearly draw the concept of railroad track capacity and the estimate on modeling of relationship railway demand and dwelling time. Also, we compare and analyze the variation of railroad track capacity according to transit railway demand in Gyeongin Line (Guro~Inchon). This paper is expected to contribute for improving on the in-using equations and methods in train operation planning as well as for improving level of service on railway user.

• Proceedings of the KSR Conference
• /
• 2011.10a
• /
• pp.2107-2114
• /
• 2011

To carry out the evaluation of performance of railway product/system, 3 step verification process(design review-lab test-field test) should be done. In advanced countries, for the effective field test, test-only-oriented track have been constructed and used. In Korea, government announced "The construction plan of railroad test track" at 2009.06. This paper will summarize 'need of test track', 'technical meaning of test track', 'current status of foreign test track', 'fundamental plan and process strategy of Korea Railroad Test Track'. It is no need to say that the wisdom of all railroad related people is required for the successful construction and usage of Korea Railroad Test Track.

• Proceedings of the KSR Conference
• /
• 2007.05a
• /
• pp.395-403
• /
• 2007

Railroad track consists of relatively simple structures such as rail, sleeper, ballast. Roadbed shares vertical pressure by train load which passed through rail to ballast as base that supports the track. For evaluating stress and displacement of roadbed due to the railroad load is an important role on the track as a basic data for estimation of the durability and design of the roadbed thickness. GEOTRACK program applied multi-layered theory was developed for analyzing railroad track structure. GEOTRACK program is a sort of numerical analysis program which has advantage that can analysis component of track by simple method. In this study, this program was used to preform the numerical analysis by changing track conditions and roadbed conditions such as tie, reinforced roadbed, dynamic wheel load, Resilient modulus and so on. Further detail will be presented on the paper.

• Journal of the Korean Society for Railway
• /
• v.3 no.2
• /
• pp.51-61
• /
• 2000

In this study, field measurements of vibration on the structures supporting railroad track were performed. The vibration data obtained were analyzed to find out any correlation between its magnitude and several factors such as type of bridges, distance from the track, type of train, frequency characteristics, etc. As a result, the magnitude of vibration turned out to be the highest in the steel bridge, the concrete bridge and steel-concrete combined bridge were the next in descending order. It was also found that the dynamic characteristics of ground were the most important factors among several affecting vibration near by the railroad track. And the empirical ground vibration estimation equation for estimating ground vibration was developed. The proposed equation with respect to distances from the railroad could be easily used for the estimation of ground vibration at the residential areas nearby the track.

• Proceedings of the KIEE Conference
• /
• 2008.07a
• /
• pp.1036-1037
• /
• 2008

Test track of the Advanced EMU system will be developed and organically combined with technologies of power supply system, signal communication system and track structure. The purpose of the test track is a acquirement of reliability and stability through a sufficient performance test. Therefore, this paper draws up all management plans for tests of the Advanced EMU system.

• Proceedings of the KSR Conference
• /
• 2007.05a
• /
• pp.486-493
• /
• 2007

In the field of maintenance of domestic high-speed railroad which has cost a great deal more than any other fields since it was opened; 1) We found out the conditions of current domestic railroad by understanding the status of track maintenance and analyzing operative processes of track maintenance. 2) The main factors in track maintenance of high-speed railroad, that is, the elements for success to help decision-support in track maintenance were derived from a research on literature about the condition of railroad R&D in these days and about the prediction of the irregular progresses of track. 3) We derived the order of priority and weights from AHP analysis which was based on the survey regarding elements for success.

• Journal of the Korean Society for Railway
• /
• v.18 no.3
• /
• pp.203-211
• /
• 2015

Ride comfort of a vehicle can be utilized to maintain the track geometry and track irregularities because ride comfort of the rolling stock is affected by the characteristics of the vehicle and track. Ride comfort was evaluated according to the measured floor acceleration data of vehicles for a Korean high speed line as well as European high speed lines using Continuous comfort method which can be applied to track maintenance. The exceedance distribution of the ride comfort was quantitatively analyzed by the vehicle speed, the ride comfort of the Korean high speed line was compared with that of European high speed lines. It is shown that the ride comfort of Korean high speed line is better than that of European high speed lines, which indicates that the Korean track geometry and track irregularities are properly maintained.

• Journal of the Korean Society for Railway
• /
• v.18 no.5
• /
• pp.447-456
• /
• 2015

Continuous as well as discrete measurement of the track geometry based on a track trolley are investigated to enhance the efficiency of the trolley and to minimize the measurement errors. A new kinematic model based on the track coordinates involving transition and circular curves is developed to improve the accuracy of the measurement; a nonlinear Extended Kalman Filter (EKF) is employed to linearize the governing equations. The proposed model is verified with the ideal track geometry in terms of both discrete and continuous measurement. Comparison with the previous models is also made to prove the applicability of the kinematic model.

• Journal of the Korean Society for Precision Engineering
• /
• v.27 no.8
• /
• pp.7-12
• /
• 2010

When a vehicle is running, wheel is generating vertical and lateral force on the rail, in addition to load of vehicle, through a complicated set of motions. The derailment coefficient refers to the ratio of lateral force to vertical force(wheel load), and if the value exceeds a certain level, a wheel climbs or jumps over the rail. That's why the value is used as a criterion for running safety. Derailment coefficient of rolling stocks alters according to shape of rail track. I measured three-dimensional angular velocity and acceleration to use 3D Motion Tracker. Test result, derailment coefficient of rolling stocks and shape of rail track examined closely that have fixed relation. Specially, was proved that roll motion has the close coupling relation.

• Proceedings of the KSR Conference
• /
• 2004.10a
• /
• pp.818-823
• /
• 2004

In case of the Korea Railroad, when we would decide the track structure, it has been introduced the whole track structure system based on only the foreign application cases and data offered by manufacturers without the process of the objective performance verification. The value of property for track materials, derived from the calculation of track structure, was hard to perform the objective performance evaluation among track structure systems because each manufacturer adopted the different test method and standard. To solve the above-mentioned problem, it should suggest the technical and objective evaluation method about the performance of track materials and meet with the standard of High Speed railroad and international railroad through the establishment and revision of performance standard. In the objective and technical respects, it will be a major role to decide the track structure. In this paper, I would like to summarize the case which was improved the problem of test method and standard exposed from the performance verification of Rail Fastening System among the track structure systems of High speed railroad.