• Structural Engineering and Mechanics
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• v.63 no.6
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• pp.713-723
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• 2017

As a new type of ballastless track, longitudinal continuous slab track (CST) has been widely used in China. It can partly isolate the interaction between the ballastless track and the bridge and thus the rail expansion device would be unnecessary. Compared with the traditional track, CST is composed of multi layers of continuous structures and various connecting components. In order to investigate the performance of CST on a long-span bridge, the spatial finite element model considering each layer of the CST structure, connecting components, bridge, and subgrade is established and verified according to the theory of beam-rail interaction. The nonlinear resistance of materials between multilayer track structures is measured by experiments, while the temperature gradients of the bridge and CST are based on the long-term measured data. This study compares the force distribution rules of ballasted track and CST as respectively applied to a long span bridge. The effects of different damage conditions on CST structures are also discussed. The results show that the additional rail stress is small and the CST structure has a high safety factor under the measured temperature load. The rail expansion device can be cancelled when CST is adopted on the long span bridge. Beam end rotation caused by temperature gradient and vertical load will have a significant effect on the rail stress of CST. The additional flexure stress should be considered with the additional expansion stress simultaneously when the rail stress of CST requires to be checked. Both the maximum sliding friction coefficient of sliding layer and cracking condition of concrete plate should be considered to decide the arrangement of connecting components and the ultimate expansion span of the bridge when adopting CST.

• The Journal of the Convergence on Culture Technology
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• v.9 no.4
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• pp.537-542
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• 2023

Recently, deformation of operating railway structures has occurred due to adjacent excavation works such as new structures and utility tunnel expansion concentrated around downtown areas. However, most of them are focused on structural review, repair and reinforcement of structures. A review of the Track is insufficient. In particular, in the case of the gravel track on the earthwork subgrade, the subgrade and the ballast are not solidified. A slight level of deformation can cause ballast relaxation. Sleeper support conditions may lead to unstable conditions. Sufficient safety must be ensured. In addition, it is a track type with a high risk of train derailment due to unstable support conditions. In this study, the correlation between the deformation characteristics of gravel tracks and track support performance according to subgrade deformation is experimentally and analytically verified. In addition, an evaluation technique that can evaluate the condition of the gravel track and the track support stiffness is presented.

• The Journal of the Korea institute of electronic communication sciences
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• v.9 no.4
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• pp.537-542
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• 2014

Track circuit is a simple electrical device which lies in the connection of the two rails by the wheels and axle of locomotives and rolling stock to short out an electrical circuit, used to detect the absence of a train on rail tracks. In railway signaling system, there are similar systems such as RFID and wheel sensor, GPS etc, are research and developing. Hybrid track circuit is using RFID antenna and reader on the cab and RFID tag on the sleeper. because of the safety in railway operation, tag detection of train position detection function in the hybrid track circuit needs high reliability. This paper studied tag recognition enhancement used tag angles.

• Proceedings of the KSR Conference
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• 2004.10a
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• pp.348-356
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• 2004

In this paper, Analysis of parameters effecting on the derailment factor was conducted in oder to deduce technical requisites have to be reflected in design of Track and rolling-stocks because it is important to grasp the risk of derailment quantitatively. And then go far toward becoming practical study with that select two section of sharp curved track of actual train in service, incheon Metro Line 1 and make field research in condition of vehicles and track and analysis As a result of parameter study, the following conclusions were obtained. The radius of curve and Cant is in inverse proportion to the derailment factor, but as train operation velocity, standard deviation of alignment irregularity and the ratio lateral force : wheel load of the inside track increase, the derailment factor rise. In the investigation for the derailment safety of incheon Metro Line 1, the derailment factor was below 0.43 in both section R=200 and R=300, so that it proved safe compare with allowance limits 0.8, but it appeared that risk of the derailment in second transition curve is the highest among the entire curve.

• Proceedings of the KSR Conference
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• 2004.06a
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• pp.328-333
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• 2004

Railway is huge traffic system which is operated organically combining all the elements; vehicle, track, electric power, signal/communication, operation, etc. Safety level has ben improved steadily by learning lessons from past accident. But with rapid progress in high-speed, massive, high-frequency transit fresh idea of accident prevention is now in order. In quest of effective and efficient countermeasure, we aim to establish an adequate safety evaluation/management method. Our proposals are basic concept relating to safety analysis of fatal accidents, AHP of Saaty, Fuzzy AHP.

• Proceedings of the KSR Conference
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• 2004.06a
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• pp.664-669
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• 2004

In rolling stock, wheels are one of the most important components to run on the track in safety. Especially, it is important that wheel profile cause the variation of dynamic characteristics and running safety. The purpose of this paper is to propose the wheel profile and to know the effectiveness of improved wheel profile by using microphones. We also performed analysis of running safety to know application of improved wheel profile before the test. In result, the improved wheel profile was stable in running safety and noise level was reduced.

• Proceedings of the KSR Conference
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• 2003.10a
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• pp.192-198
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• 2003

Railway is huge traffic system which is operated organically combining all the elements; vehicle, track, electric power, signal/communication, operation, etc. Safety level has been improved steadily by learning lessons from past accident. But with rapid progress in high-speed, massive, high-frequency transit fresh idea of accident prevention is now in order. In quest of effective and efficient countermeasure, we aim to establish an adequate safety evaluation/management method. Our proposals are basic concept relating to safety analysis of fatal accidents, AHP of Saaty, Fuzzy AHP.

• Proceedings of the KSR Conference
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• 2001.10a
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• pp.422-428
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• 2001

This paper provides a brief overview of the process for the introduction of new train in England since privatization in 1994. They have railway safety case which the safety management for the introduction of new trains is to be considered in all process including design, manufacturing, test, maintenance etc. To achieve safety in track, they also consider evidence available from the design and build process.

• The Journal of the Korea institute of electronic communication sciences
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• v.8 no.12
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• pp.1905-1910
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• 2013

This paper demonstrates the result of Safety Integrity Level (SIL) allocation for IL-type Train Control System(IL-TCS), by applying the semi-quantitative approach. IL-type TCS is defined in this paper as the set of Hardware and Software ATS equipment, Track-side ATP equipment, On-board ATP equipment, Track-side ATO equipment, On-board ATO equipment. SIL allocation is performed for these constituent subsystems of TCS. Based on three principles of the semi-quantitative method, the SIL allocation process is performed for the subsystems composing TCS.

• Proceedings of the KSR Conference
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• 2000.05a
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• pp.210-217
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• 2000

This paper estimates the derailment factor of running train on the curved track. To estimate the derailment factor, wheel loads and lateral forces of train are measured on the track. The selected measuring points are the 400R and the 600R in the Honam line, the 300R and the 400R in the Janghang line, respectively. The derailment factors are evaluated from the wheel loads and lateral forces which are measured on the all axles of running trains.