• 한국소음진동공학회논문집
• /
• 제17권10호
• /
• pp.993-1001
• /
• 2007

An analysis model has been developed to assess running safety of railway vehicle passing curves. By using ADAMS/Rail, a computer analysis has been conducted by changing various parameters according to the track conditions. Analysis results show as follows: A derailment coefficient of left wheel was increased according to increase of cant at low speed, while it was decreased as increase of cant at high speed. A unload rate of left wheel was also increased according to increase of cant at low speed, while it was decreased as increase of cant at high speed. A wear number of left wheel was increased according to increase of cant at all speed, but only at 35 m/s, it was decreased as increase of cant. A friction coefficient of left wheel was Increased according to increase of cant at all speed, but only at 35 m/s. it was decreased as increase of cant.

• International Journal of Railway
• /
• 제2권4호
• /
• pp.180-186
• /
• 2009

High speed railway challenge the design, construction and maintaining of traditional railway, many traditional design concepts have been changed. Transition of railway and bridge has two main problems. one is that different lines have different ability of resisting distortion in area of trial load, which was known that problem of smooth transition of stiffness, the other is that differential settlement between artificial structure and earth structure cause bending of railway. The two problems have effect on train moving. The principle of processing transition of railway and bridge is same in world, but it is difficult to find relationship between design standard of transition, vehicle performance, line standard, design speed and so on form documentation and data reports. Based on mechanics, the paper analyzed dynamic performance of transition of high speed railway, studied various rough elements which is effective to train moving, built mathematical model of interaction of train and transition of high speed railway and developed numerical simulation software. In various different work conditions, we did great quantity of numerical simulation, comprehensive analysis and performance analysis.

• 한국정밀공학회지
• /
• 제32권7호
• /
• pp.597-602
• /
• 2015

In this paper, we studied the steering performance of wheelset with primary suspension characteristics of railway vehicle. We carry out dynamic analysis and experimental study for the vehicle models which are different primary suspension characteristics. The steering angle of a vehicle model (Case 1) operating in domestic subway lines is insufficient compared with an objective steering angle for curved track. And the steering angle of a vehicle model (Case 2) with improved self-steering performance of wheelset is a little improved compare to previous vehicle model. But also Case 2 model is still insufficient compared with an objective steering angle and has its limit in steering performance. So to overcome this limit of steering performance of passive type railway vehicle, an active steering technology is being developed. In case of vehicle model with active steering system, the steering performance is improved remarkably compared to passive type vehicle model.

• 한국철도학회:학술대회논문집
• /
• 한국철도학회 2008년도 추계학술대회 논문집
• /
• pp.380-386
• /
• 2008

The development of a new railway vehicle is under progress through the Next Generation High-Speed Rail Development Project in Korea. Its aim is to develope fundamental technology of the vehicle that can run over 400km/h. The new distributed traction bogie system, 'HEMU'(High-speed Electric Multiple Unit), will be used and is different from that of previously developed high speed railway vehicles. Previous vehicles adopted push-pull type system, which means one traction-car drives rest all of the vehicle. Due to the difference, investigation on dynamic behavior and its safety evaluation are necessary, as a part of verification of the design specification. In the paper, current progresses of researches are presented. And the High-Speed Railway vehicle system is evaluated for a dynamic characteristic simulation. Proper dynamic models including air-suspension system, wheel-rail, bogie and car-body is developed according to the vehicle simulation scenario. The basic platform for the development of dynamic solver is prepared using nodal, modal coordinate system and wheel-rail contact module. Operating scenario is prepared using commercial dynamic analysis program and used for development of dynamic model, which contains many parts such as carbodies, bogies and suspension systems. Furthermore, international safety standard is applied for final verification of the system. Finally, the reliability of the dynamic model will be verified with test results in the further researches. This research will propose a better solution when test results shows a problem in the parts and elements. Finally, the vehicle that has excellent performance will be developed, promoting academic achievement and technical development.

• 한국철도학회:학술대회논문집
• /
• 한국철도학회 2011년도 춘계학술대회 논문집
• /
• pp.960-964
• /
• 2011

High speed railway structure, contact of vehicle needs to design considering the running stability(dynamic behavior). Also, upper structure has to satisfy design standard about moving load, high speed train(KTX). So, the high speed railway structure has to satisfy the requirement of natural frequency, vertical acceleration on deck, face distortion and vertical displacement considering ride comfort, which is suggested Ho-nam high speed railway design standard. In this study, it was investigated and evaluated to the dynamic behavior for tow plate Girder railway bridge subjected to moving load considering real high speed train loads.

• 한국철도학회:학술대회논문집
• /
• 한국철도학회 2010년도 춘계학술대회 논문집
• /
• pp.1138-1142
• /
• 2010

High speed railway structure, contact of vehicle needs to design considering the running stability(dynamic behavior). Also, upper structure has to satisfy design standard about moving load, high speed train(KTX). So, the high speed railway structure has to satisfy the requirement of natural frequency, vertical acceleration on deck, face distortion and vertical displacement considering ride comfort, which is suggested Ho-nam high speed railway design standard. In this study, it was investigated and evaluated to the dynamic behavior for a double-rib arch railway bridge subjected to moving load considering real high speed train loads.

• 한국철도학회논문집
• /
• 제20권5호
• /
• pp.577-587
• /
• 2017

철도차량이 고속화될수록 동적특성 설계에 있어 주행안정성 해석, 시험 및 평가 기법의 중요성이 커지고 있다. 특히 철도차량이 실제 선로에서 임계속도에 도달하면 헌팅에 의한 윤축의 과도한 진동으로 탈선 등의 중대 사고가 발생할 가능성이 높아 거의 대부분의 임계속도 시험 및 평가는 해석으로 대체하거나 주행시험대 같은 특수한 장비를 이용하여 수행되고 있다. 본 논문에서는 철도차량의 임계속도를 시험하고 평가하는 방법을 고찰하고 그 유용성을 실제 주행시험대 시험을 통해 확인하였다. 시험결과로부터 UIC 518에서 제시한 대차 가속도를 이용한 안전성 및 불안정 평가는 임계속도와 상관관계가 낮아 임계속도를 추정하는데 직접적으로 활용되기 어려우며, 등가감쇠비의 변화를 이용한 추정방법이 더 유효한 것으로 분석되었다.

• 한국철도학회:학술대회논문집
• /
• 한국철도학회 2005년도 추계학술대회 논문집
• /
• pp.1261-1267
• /
• 2005

At this paper Dynamic respones of bridges for the Korean high-speed railway are analyzed by a modal analysis. To control vibration of bridges, Tuned Mass Damper(TMD) that is passive type control device is used. Opimize and prove it. Newmark method is used for a numerical analysis. In case of vehicle is modeled for moving mass that considers the effects of the moving. Also this paper is assumped as the simple supported Bernoulli-Euler beam and considered two dimensional Interaction motion between vehicle and bridge.

• 한국철도학회논문집
• /
• 제13권3호
• /
• pp.245-250
• /
• 2010

본 논문에서는 안정성과 안전성 해석을 통하여 차세대 고속철도(HEMU-400X)의 주행성능을 예측하였다. 차량의 설계단계에서 주행성능을 예측하는 것은 차량의 안전 확보를 위해 매우 중요하다. 안정성 해석을 통하여 차륜의 등가 답면구배에 따른 임계속도를 계산하였다. 임계속도는 UIC518에 근거하여 등가 답면구배 0.15에서 400km/h가 달성 가능함을 보였다. 또한 안전성 해석을 통하여, 동역학 모델의 횡방향과 수직방향의 가속도 값을 시뮬레이션 하였다. 안정성 해석은 UIC518에 근거하여 440km/h의 속도로 30km의 구간을 주행하였다. 그리고 계산된 값들은 모두 UIC518의 최대 허용 가속도 값보다 적게 나타나는 것을 확인하였다.

• Structural Engineering and Mechanics
• /
• 제80권5호
• /
• pp.491-501
• /
• 2021

A difference in subgrade settlement between two rails of a track manifests as lateral differential subgrade settlement. This settlement causes unsteadiness in the motion of trains passing through the corresponding area. To illustrate the effect of lateral differential subgrade settlement on the dynamic response of a vehicle-track coupling system, a three-dimensional vehicle-track-subgrade coupling model was formulated by combining the vehicle-track dynamics theory and the finite element method. The wheel/rail force, car body acceleration, and derailment factor are chosen as evaluation indices of the system dynamic response. The effects of the amplitude and wavelength of lateral differential subgrade settlement as well as the driving speed of the vehicle are analyzed. The study reveals the following: The dynamic responses of the vehicle-track system generally increase linearly with the driving speed when the train passes through a lateral subgrade settlement area. The wheel/rail force acting on a rail with a large settlement exceeds that on a rail with a small settlement. The dynamic responses of the vehicle-track system increase with the amplitude of the lateral differential subgrade settlement. For a 250-km/h train speed, the proposed maximum amplitude for a lateral differential settlement with a wavelength of 20 m is 10 mm. The dynamic responses of the vehicle-track system decrease with an increase in the wavelength of the lateral differential subgrade settlement. To achieve a good operation quality of a train at a 250-km/h driving speed, the wavelength of a lateral differential subgrade settlement with an amplitude of 20 mm should not be less than 15 m. Monitoring lateral differential settlements should be given more emphasis in routine high-speed railway maintenance and repairs.