• 한국정밀공학회지
• /
• 제27권8호
• /
• 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.

• 한국철도학회:학술대회논문집
• /
• 한국철도학회 2008년도 춘계학술대회 논문집
• /
• pp.1653-1661
• /
• 2008

A trial run of locally-developed tilting train has been in process on Chungbuk line since the test vehicle was first produced. For the system stabilization, interface verification among the systems including track, structure, catenary and signaling system, not to mention the rolling stock, is very crucial. In the area of wayside structure, the stability of track structure and train run shall be evaluated through the review of impact by increased speed by developed train on track structure. The study thus was intended to evaluate the impact on track while a tilting train is running the conventional line(ballast track), which is vulnerable to accelerated train speed. The evaluation of tilting train test running the part of Honam line was conducted to identify the impact on existing track performance by tilting train. To identify the performance of each part of track components while tilting train and high speed train were running the existing line, wheel load, rail bending stress, vertical displacement of rail and sleeper were compared so as to evaluate the expected impact by tilting train for improving the train speed.

• 한국소음진동공학회논문집
• /
• 제18권12호
• /
• pp.1301-1309
• /
• 2008

The curved portion fur each section running safety evaluation interpretation according to the track condition for improving the curved portion passage rate of a vehicle by using the multibody analysis model of the Saemaeul train was carried out. As a result, The excess of cant reaches the bad effect to the running safety in case the radius of curvature is small. In case the radius of curvature was large, we could confirm that the deficiency of cant reached the bad effect to the running safety. In the curved portion, the circular curve section most badly showed the running safety. The deficiency of curve length reaches the bad to the running safety. In the curved portion, the circular curve section most badly showed the running safety. Therefore the track condition(cant, transition curve length, etc) can reach the bad effect to the running safety of a vehicle, the exact design is required.

• 한국철도학회논문집
• /
• 제15권2호
• /
• pp.172-178
• /
• 2012

현행 철도건설기준에서 종곡선과 완화곡선의 경합은 궤도형식에 관계없이 허용하고 있지 않다. 그러나 이러한 기준은 주로 자갈도상궤도의 유지보수의 어려움 때문에 정립된 것이다. 콘크리트궤도는 자갈도상궤도에 비해 유지보수 및 구조안전성 측면에서 장점을 가지고 있다. 따라서 콘크리트 궤도의 경우, 열차의 주행안전성 및 승차감 기준을 만족하는 범위내에서 어느 정도의 선로경합은 완화할 필요성이 있다. 본 연구에서는 종곡선과 완화곡선의 경합여부에 따라 도상종별 열차의 주행안전성 및 승차감, 그리고 궤도작용력을 비교 분석하였으며, 그 결과 경합된 경우도 주행안전, 승차감 및 궤도작용력 기준을 만족하는 것으로 나타났다. 따라서, 비록 자갈도상궤도에서의 선로경합은 많은 유지보수를 필요로 하기 때문에 적용될 수는 없다 할지라도, 콘크리트궤도에서는 유지보수 및 구조적 장점을 고려할 때 종곡선과 완화곡선의 경합이 적용될 수 있을 것으로 판단된다.

• 한국안전학회지
• /
• 제31권3호
• /
• pp.130-135
• /
• 2016

It is very hard to analyze the train derailment safety quantitatively at the curved section because of the diversified affect parameters including the complex interaction between wheel and rail, the train conditions such as the shape of wheel, suspension system, the track conditions such as the radius of curve, cant, transition curve, and the operation conditions, etc. Two major factors related to the running safety of railway vehicle are classified as the railway vehicle and the track condition. In this study, when the railway vehicle passing through curves of actual track condition of subway line NO.3 in seoul ($Yeonsinnae{\leftrightarrow}Gupabal$), the effect that has influence on running safety depending on rail inclination. The analysis result of 1/40 rail inclination condition is more favorable on running safety than other rail inclination conditions because derailment coefficient and wheel unloading ratio are the lowest.

• 한국철도학회:학술대회논문집
• /
• 한국철도학회 2007년도 춘계학술대회 논문집
• /
• pp.1855-1860
• /
• 2007

The high speed tilting train has superior advantages which are effects on reductions of running time to non-tilting in curves. But in order that the tilting train is operated in conventional track, it is performed evaluation on the running safety. This study carried out an analysis of running stability of tilting train in conventional curved track. The results obtained through this study will be applied to improve the conventional curved track and determine the limit velocity.

• 한국소음진동공학회:학술대회논문집
• /
• 한국소음진동공학회 2007년도 춘계학술대회논문집
• /
• pp.297-303
• /
• 2007

Derailment is likely to have a direct connection with human life and must be eliminated. A traveling safety evaluation method based mainly on derailment coefficient has already established. But this method is very difficult because Derailment is caused by multiple factors. To evaluate the derailment factor of running train that runs on the curved track, we make use of mechanism that wheel loads and lateral forces were affected by track and rolling stock parameter. In this paper, deal with a search on the parameter and derailment factor. According to results of computer simulation value of Q/P, running safety is connected with operation velocity, curve radius, cant, track irregularity, suspension stiffness and static wheel load ratio, SMRT train Line No. 5 Bogie is selected to do numerical study considering rolling stock and track condition.

• 한국산학기술학회논문지
• /
• 제18권10호
• /
• pp.717-724
• /
• 2017

콘크리트 매립형 궤도를 운행하는 트램의 주행 안전성을 향상시키기 위해 핵심 구성품인 대차를 개발하고 제작하여 시험 차체와 조립한 후, 단거리 급곡선 급경사 궤도를 건설하고 시험운행을 실시하였다. 대차의 급곡선 주행 중 차륜 플랜지와 매립형 궤도의 간섭을 검토할 수 있는 산식을 제시하였고, 산식 결과에 따라 궤도를 설계하였다. 간략화된 계산식을 도출하여 곡선에서 탈선계수와 윤중감소율을 추정하였다. 단거리 급경사 급곡선 매립형 궤도에서 대차와 차체가 주행할 때에 차체의 가속도를 계측하였고, 영상 시스템을 통해 차륜과 궤도의 인터페이스 상태를 점검하였다. 계산 추정 결과에 따르면 차륜의 탈선계수와 윤중감소율은 안전기준 이하였는데, 실제 주행 시험 중에도 탈선은 발생하지 않았고, 가속도 계측 결과도 주행 안전기준을 만족하였다. 또한, 차륜과 궤도의 간섭은 발생하지 않았고, 영상 모니터링 결과도 차륜의 올라타기 등 탈선조짐은 발견되지 않았으며, 중앙의 피니언과 랙이 원활히 접촉하면서 양호한 주행안전성을 보여주고 있었다. 외부 소음 계측을 통해서 소음 기준을 만족하고 있음을 확인하였다.

• 한국소음진동공학회논문집
• /
• 제23권3호
• /
• pp.199-208
• /
• 2013

So far today, there is a speed limit by the radius of curve based on operation regulation in domestic railway, however a study for the maximum running speed at the curved section without any derailment would be necessary. The two major factors related to the running safety of railway vehicle are classified as the railway vehicle condition and the track condition. In terms of the rail inclination among many other factors, the determination of rail inclination within the possible limit is necessary for the geometrical structure of the optimum track. The disregard of the geometrical parameter related to the rail inclination may cause a serious problem to the running safety of railway vehicle. This study is focusing on the analyzing of running safety regard to the change of rail inclination among the many other parameters to improve derailment safety, so that there is an affection analysis of the running safety regard to the change of rail inclination in the ideal and geometric track condition. Also There is an affection analysis of the running safety regard to the simultaneous change of rail inclination and the running speed at the curved section. According to analysis results of running safety, In case that the left and right rail inclination are 1/40, the running safety of this condition defined than other conditions. Also, the rail inclination of conventional lines is 1/40, Therefore, the railway vehicle passing through curve is safe when the railway vehicle runs in conventional lines.

• 한국철도학회:학술대회논문집
• /
• 한국철도학회 2000년도 춘계학술대회 논문집
• /
• pp.210-217
• /
• 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.