• 한국철도학회논문집
• /
• 제7권4호
• /
• pp.332-338
• /
• 2004

The two projects about the high speed train have been performed in Korea, one project is the commercial run of high speed train(KTX) from Seoul to Busan and the other is the development of original high speed train(HSR 350x). As the successful results, the service run of KTX had been launched on the 1st of April, 2004 and HSR 350x had been fabricated in June, 2002 and has been tested in the Kyoungbu line and Honam line since then. The railway has the track irregularities which cause vibrations, such as rail joints, turnout, level crossing, transition curves and super-elevation ramps, and variations in the track level(z-axis) and the gauge(y-axis). Generally, the ride comfort for railway is evaluated by using the vibrations. In this paper, the ride comfort indices according to mc 513R and ISO 10056 have been reviewed when the high-speed trains are operated on both Kyoungbu line and Honam line. Also, the ride characteristics for KTX and HSR 350x on the high speed line and the conventional line have been analyzed and evaluated. The results show that the high-speed train has no problem from the viewpoint of the comfort ride on the high speed line and the conventional line and the ride index for HSR 350x is same as that for KTX in the high speed(300 km/h).

• Structural Engineering and Mechanics
• /
• 제81권2호
• /
• pp.219-230
• /
• 2022

Due to the large number of railway bridges along China's high-speed railway (HSR) lines, which cover a wide area with many lines crossing the seismic zone, the possibility of a HSR train running over a bridge when an earthquake occurs is relatively high. Since the safety performance of the train will be threatened, it is necessary to study the safety of trains running over HSR bridges during earthquakes. However, ground motion (GM) is highly random and selecting the appropriate ground-motion intensity measures (IMs) for train running safety analysis is not trivial. To deal this problem, a model of a coupled train-bridge system under seismic excitation was established and 104 GM samples were selected to evaluate the correlation between 16 different IMs and train running safety over HSR bridges during earthquakes. The results show that spectral velocity (SvT₁) and displacement (SdT₁) at the fundamental period of the structure have good correlation with train running safety for medium-and long-period HSR bridges, and velocity spectrum intensity (VSI) and Housner intensity (HI) have good correlation for a wide range of structural periods. Overall, VSI and HI are the optimal IMs for safety analysis of trains running over HSR bridges during earthquakes. Finally, based on VSI and HI, the IM thresholds of an HSR bridge at different speed were analyzed.

• 한국지반공학회:학술대회논문집
• /
• 한국지반공학회 2001년도 봄 학술발표회 논문집
• /
• pp.245-248
• /
• 2001

During the core drilling for the design of a railway bridge crossing over the inferred fault system along the river, fracture zone, extends vertically more than the bottom of borehole, filled with fault gouge was found. The safety of bridge could be threatened by the excessive subsidence or the reduced bearing capacity of bedrock, if a fault would be developed under or around the pier foundation. Thus, a close examination of the fault was required to rearrange pier locations away from the fault or to select a reinforcement method if necessary. Geophysical methods, seismic reflection method and electrical resistivity survey over the water covered area, were applied to delineate the weak zone associated with the fault system. The results of geophysical survey clearly showed a number of faults extending vertically more than 50m. Reinforcement was not desirable because of the high cost and the water contamination, etc. The pier locations were thus rearranged based on the results of geophysical surveys to avoid the undesirable situations, and additional core drillings on the rearranged pier locations were carried out. The bedrock conditions at the additional drilling sites turned out to be acceptable for the construction of piers.

• 한국철도학회논문집
• /
• 제7권3호
• /
• pp.193-199
• /
• 2004

Numerical analysis of aerodynamic characteristics was differently performed according to the running situation of the Korean Tilting Train eXpress(TTX) that would be introduced for an improvement in efficiency of the used railroad track. Fluent 6.0 was used for the analysis of Non-tilting case, Tilting case and Passing-by case with the model of TTX. As a result, the aerodynamic drag had little difference between Tilting and Non-tilting case. However, pressure contour under the train of Tilting case was not symmetry because the gap between a train and the ground was different at both sides. In Passing-by case attraction and counterattraction occurred alternately and affected to the opposite train. When two trains were side by side, the maximum attraction was generated especially. Through an analysis of pressure wave in tunnel a large variation of pressure was generated by the bluff nose of TTX. The results in this study would be good data for the aerodynamic characteristic on TTX and provide important information to judgment of running safety.

• 한국철도학회논문집
• /
• 제19권2호
• /
• pp.170-186
• /
• 2016

본 논문에서는 철도 시스템에서 안전무결성수준 평가를 위한 다단계 퍼지 리스크 그래프를 제안한다. 본 모델은 입력변수의 모호함과 주관적 전문가 판단의 단점을 보완하는 것을 목적으로 한다. 다단계 퍼지 리스크 그래프 모델은 2단계로 구성된다. 본 논문에서는 첫 번째 퍼지화를 위한 상세 입력 변수가 제안되고 첫 번째 단계에서 퍼지 이론을 적용하여 기존의 리스크 그래프 입력 변수인 심각도, 노출도, 회피도, 요구율을 산정한다. 퍼지 추론 및 역퍼지화 결과 2단계에서 적용할 입력변수가 도출된다. 두 번째 단계에서는 식별된 해당 해저드에 대하여 안전 무결성 수준과 허용 해저드율을 산정하여 안전 요구사항을 수립한다. 또한 다단계 퍼지 리스크 그래프 모델을 검증하기 위해 CENELEC SC 9XA WG A10 보고서에 소개된 건널목 시스템을 대상으로 한 안전성 평가 결과와 비교하여 모델을 검증하였으며, 철도 분야의 초기 개념 설계 단계 안전성 요구사항을 수립 시 적용할 수 있다.

• 한국철도학회논문집
• /
• 제19권4호
• /
• pp.555-563
• /
• 2016

선로용량은 수요에 부합되는 최대열차횟수를 결정하고 수송력 증대에 필요한 투자우선순위 판단을 위한 중요한 척도이다. 특히 2016년 중반부터 고속철도노선에 두 철도운영자가 운송사업을 개시함에 따라 선로용량과 실제배정 가능한 최대열차횟수 간에 상충이 발생하지 않고 유효운송경쟁이 보증될 수 있도록 선로용량을 산정 관리할 필요성이 있다. 열차종별 운행횟수, 도중정차패턴과 착발시각, 운행시간, 열차의 대피 또는 교행, 열차간의 안전시격 등에 따라 선로용량이 크게 달라지므로 현재까지도 실제 적용에 많은 논쟁이 있는 것도 사실이다. 이러한 문제점을 극복하고자 철도운영자의 운송정책을 고려한 열차운행 스케쥴을 반영할 수 있는 시뮬레이션 기법에 의한 선로용량 산정방법을 제시하고자 한다.

• 한국철도학회:학술대회논문집
• /
• 한국철도학회 2011년도 춘계학술대회 논문집
• /
• pp.1014-1022
• /
• 2011

Urban transit operation is to manipulate the vehicle or train of urban transit to be operated on the basis of the installations such as track, power, communication, signaling and so on. It can be performed by manual or automated, or manned or manless operation considering its system built, operation efficiency, safety, etc. Because of the heavy impact directly to the safety of passenger transport, it has been managed strictly by the Regulation for Train Operation of Urban Transit according to Urban Transit Act. However, the present regulation has been basis of the manual operation mainly, it is crossing beyond the limitation of application to the manless operation which is being introduced moment to moment. It is needed increasingly to revise the regulation for the manless operation which is close at hand now. In this paper, we examined and analysed the cases of manless operation of urban transit planed within the country such as Busan 4th Line, Shinbundang Line, Busan-Kimhae Line, etc. based on the present regulation, and proposed the review of considerations to reflec the manless operation to the regulation to be revised.

• 한국철도학회:학술대회논문집
• /
• 한국철도학회 2011년도 춘계학술대회 논문집
• /
• pp.652-659
• /
• 2011

Due to overuse of commercial network systems such as bluetooth and WI-FI, the problems of frequency interruption and line-crossing may arise. For this reason, wireless communication frequency ISM 2.4GHz, a recently adapted concept in Korea which is employeed by RF-CBTC system, is predicted not to have guarantee for outstanding and continuous performance. Therefore in this study, considering these problems, 5GHz capacity wireless Lans with international standard 802.11a/b/g applied were installed in the underground urban transit areas and it was proved that these lans exceeded the performance level of 2.4GHz with international standard 802.11b which is being introduced in the nation. In addition, it was verified through carrying out an application test that the communication condition was stable in a running train with high speed in the tunnel.

• 한국정밀공학회:학술대회논문집
• /
• 한국정밀공학회 2005년도 춘계학술대회 논문집
• /
• pp.322-325
• /
• 2005

TTX(Tilting Train eXpress) is being designed for improving the speed of conventional railway. The purpose of this study is to evaluate energy absorbing capacity and driver's survivability for a design candidate of the front end structure of TTX. A FE model with honeycomb block, under frame, and body frame is generated for crash simulation. Based on a level-crossing accident scenario, numerical simulation is performed using LS-DYNA. The results of crash analysis show that strength improvement of the current front end structure design candidate is needed to ensure driver safety.

• 한국정밀공학회:학술대회논문집
• /
• 한국정밀공학회 2005년도 춘계학술대회 논문집
• /
• pp.318-321
• /
• 2005

Crashworthy design of a train is a systematic approach to ensure the safety of passengers and crews in railway transportation for the prescribed accident scenarios. This approach needs new structural arrangements and designs to absorb higher levels of impact energy in a controlled manner and interior designs to minimize passenger injuries. In this paper, an evaluation method for crashworthiness of Korean tilting train express is introduced. Crush characteristics for each part of tilting train express are evaluated numerically through 3-dimensional shell element analysis with LS-DYNA. Based on a head-on collision and a level crossing collision scenarios, the crash behaviors of tilting train express are evaluated numerically using full-rake collision simulations.