고속철도 자갈궤도 틀림과 보수간의 상관관계 분석

박현우(Hyun-Woo Park),장승엽(Seung Yup Jang),박성백(Seong-Baik Park) 한국철도학회 2014 한국철도학회 학술발표대회논문집 Vol.2014 No.10

최근 3 년간 종합검측차로부터 수집된 궤도틀림 데이터와 궤도보수이력을 이용하여 고속철도 자갈궤도 틀림과 보수간의 상관관계를 분석한다. 궤도틀림 정량화를 위해 200m 구간 궤도틀림 표준편차로 정의되는 궤도품질지수(Track quality index; TQI)를 사용한다. 궤도품질지수의 시계열 추이를 분석하기 위해 선형 회귀분석을 수행한다. 특정 보수시점의 전후에 대한 궤도품질지수 변화는 조각 선형 회귀분석을 이용하여 정량화한다. 회귀분석 결과 자갈궤도 보수효과가 뚜렷하게 나타나는 개소는 보수시점 전후에서 궤도틀림 데이터의 누적확률분포를 추정한다. 이를 통해 보수작업에 따른 궤도품질지수의 변화와 실제 궤도틀림의 통계적 분포 변화의 상관관계를 분석한다. This paper presents correlation analysis between track irregularity and maintenance using track irregularity data collected by track inspection car and track maintenance history during last three years. Track irregularity is quantified through track quality index (TQI) being defined by 200m-section standard deviation of track irregularity data. A linear regression analysis is conducted to analyze the time-series chart of track irregularity. Piecewise linear regression is employed to quantify the change of track quality index due to track maintenance at a specific moment. At the spot where the effect of track maintenance appears clearly, a cumulative probability distribution is identified for the raw track irregularity data collected before and after the track maintenance. Correlation analysis is performed between the changes of track quality index due to track maintenance and statistical distribution for raw track irregularity data.

Post-earthquake track irregularity spectrum of high-speed railways continuous girder bridge

Yulin Feng,Lizhong Jiang,Wangbao Zhou,Mengcheng Chen 국제구조공학회 2021 Steel and Composite Structures, An International J Vol.40 No.3

To study the track irregularity spectrum for CRTS II ballastless track continuous girder bridge for high-speed railway (CBTCGB) after the action of earthquake, a line-bridge integration seismic calculation model was established. By considering the randomness of structural parameters and ground motion, large amounts of samples were analyzed for additional track irregularity caused by factors such as earthquake-induced damage and earthquake-induced void of key components between the layers of track-bridge system. Using improved Blackman-Turkey method and Levenberg- Marquardt algorithm, the earthquake damaged CBTCGB track irregularity spectrum, track irregularity spectrogram, and a fitting formula for track irregularity spectrum after the action of near-field earthquake were obtained, and the calculation results obtained from the fitting formula and CBTCGB numerical model were compared. The results indicate that the probability sampling distribution of ground motion and structural parameters selected according to “binning method” can effectively reflect the randomness of ground motion and structural parameters. The track irregularity spectrum line forms can be roughly divided into three ranges, namely, high-frequency, medium-frequency, and low-frequency waveband. The tracks suffer more track irregularity diseases with high-frequency after earthquake, which is necessary to conduct tracking analysis. It is rational to use a three-segment power function for the fitting of track irregularity spectrum after the action of earthquake.

궤도틀림의 검측값과 측량결과 비교

이지하(Lee Jeeha),최일윤(Choi iI-Yoon),김박진(Kim Bak-Jin) 한국철도학회 2008 한국철도학회 학술발표대회논문집 Vol.- No.-

Track geometry changes by traffic loads. The bigger the changes are, the worse the riding comfort and running stability of train. This is so-called track irregularity and is the most important quality parameters of ballasted track. To objectively assess track irregularity, track geometry should be able to be measured. Practically, railway companies use moving chord method, which determine versine values via a chord. The versine is the vertical distance to curve measured in the middle of the chord. This type of method measures only versine of track irregularity curve by transfer function from the characteristics of measuring device. In this report , review the characteristics of two types of measuring tools by comparing the measurements. The one is GRP-1000 system, optical surveying system with Total station and lazar prism trolly. This calculates track geometry by surveying absolute coordinates of two points each on both rail heads. The other is EM-120, measures versine with 10m of symmetrical chord length.

Effect of Rail Irregularities and Rail Pad on Track Vibration and Noise

Naveen Kumar Kedia,Anil Kumar,Yogendra Singh 대한토목학회 2021 KSCE JOURNAL OF CIVIL ENGINEERING Vol.25 No.4

This paper focuses on the effect of short and long wavelength track irregularities and rail pads on train induced vibration and noise using a train-track interaction model. An Indian rail vehicle is modelled as a spring-mass-damper system, and a ballasted track structure is modelled as an infinite rail resting on the viscoelastic foundation. Long-wavelength track irregularity is obtained from measured field data; however, short-wavelength track irregularity is generated using Sato track spectrum. It is observed that vibration and noise levels are not only higher for short-wavelength compared to long-wavelength but also exceed the limits imposed by the Indian Railway standards. Thus, track properties are modified by varying stiffness and damping of rail pads to reduce vibration and noise levels. The stiffer pads reduced vibration level in the range of 7dB-24dB and noise level in the range of 8dBA-14dBA; hence, stiffer pads are recommended for the ballasted track. Moreover, track properties for short-wavelength also keep vibration and noise levels within the permissible limit for long-wavelength. Thus, modification of track properties based on only short-wavelength irregularity is required.

인접지반 깊은 굴착시 도시철도 궤도 안정성 평가

이상승(Sang-Seung Lee),이성진(Sung-Jin Lee),박영곤(Yeong-Gon Park),전상수(Sang-Soo Jeon) 한국철도학회 2016 한국철도학회 학술발표대회논문집 Vol.2016 No.5

대부분의 시설이 지중에 시공된 도시철도는 인접 지역 공사 진행 시 동반되는 굴착공사로 인하여 지반이완에 따른 응력변화를 갖게 된다. 이는 지하구조물의 침하 및 융기로 이어져 구조물 내에 시공된 궤도의 선로변형을 초래하며 궤도틀림을 유발한다. 궤도틀림은 승차감 저하 및 주행 안정성을 감소시키며 지속적인 점검 및 보수가 이루어지지 않을 경우 차량의 탈선과 전복을 발생시킬 수 있는 매우 중요한 요소이다. 따라서 본 연구에서는 삼차원 유한차분해석 프로그램 FLAC3D를 이용하여 도시철도 인접지반 대규모 굴착 발생 시 지반 특성에 따른 박스구조물 내에 시공된 궤도틀림량 산정 후 국내 도시철도 궤도틀림 기준을 적용하여 안정성 평가를 수행하였다. 굴착시 지반조건 변화에 의한 궤간틀림의 변위 차는 매우 미소하게 발생하였으나 줄틀림, 수평틀림, 면틀림, 평면성틀림은 각각 56%, 55%, 76%, 75%가 발생하였다. Most of facilities of urban railway are constructed in underground and, as a deep excavation for a high rise building construction is undergoing adjacent to the urban railway, the strength of soil is changed by the ground loss. Settlement and heaving of underground structures causes a track transformation and irregularity. Track irregularity is very important factor because it reduces a comfortable ride and driving stability and, if continuous check and repairs are not carried out, it causes a derailment and overturning of train. In this study, stability assessments using a commercial three-dimensional finite difference model, FLAC3D, are carried out to examine a track irregularity of underground box structures associated with the ground characteristics based on the standards of track irregularity provided by each metropolitan as a deep excavation undergoes adjacent to the urban railway. Track gauge irregularity associated with ground variation is relatively very small but alignment irregularity, cross level irregularity, longitudinal irregularity, and twist irregularity are 56%, 55%, 76%, and 75%, respectively.

도시철도 인접굴착공사에 따른 운행선 궤도의 궤도틀림 분석

최정열,이호현,강유송,정지승 국제문화기술진흥원 2020 The Journal of the Convergence on Culture Technolo Vol.6 No.2

본 연구는 도시철도 선로를 인접하여 시공되는 대형굴착공사에 따른 기존 지하철 선로구조물의 구조적 안정성을 검토하고자 수치해석을 수행하였다. 수치해석을 바탕으로 단계별 시공과정에서 발생되는 궤도틀림의 영향을 해석적으로 도출하였으며 관련 기준과의 비교를 통해 궤도변형측면에서의 안정성을 검토하였다. 분석결과, 줄틀림과 면틀림과 같이 일정거리에서의 상대변위차를 바탕으로 평가되는 궤도틀림 항목의 경우 인접굴착공사 시종점부와 같이 기존 구조물의 변형이 시작되는 위치에서 가장 명확하게 발생되었다. 반면 궤도의 전반적인 연직 및 수평변위는 공사구간의 중심에서 최대변형이 발생되었다. 인접굴착공사에 따른 기존 구조물의 변형측면의 취약위치는 공사구간의 중심과 같이 구조물의 변형이 크게 발생되는 위치뿐만 아니라 궤도틀림 측면에서는 공사 시종점 구간이 취약위치가 될 수 있음을 해석적으로 입증하였다. In this study, finite element analysis was performed to evaluate the track irregularity of the existing track system on urban transit according to the large-scale excavation work that is constructed adjacent to the serviced line. Based on the numerical analysis, the effect of track irregularity generated during the step-by-step construction process was analytically derived, and the stability in terms of track deformation was evaluated through comparison with related standards. As the results, in the case of track irregularity items evaluated based on the relative displacement difference at a certain distance, such as alignment and vertical irregularity, it occurred most clearly at the location where deformation of the existing structure begins, such as the end point of adjacent excavation work. On the other hand, the overall vertical and horizontal displacement of the track was the largest deformation at the center of the construction section. The vulnerable position of the deformed side of the existing structure due to adjacent excavation is analytically proven that the both of the end point section and the center of the construction can be a vulnerable position in terms of track irregularity.

측량과 현방식 궤도틀림 측정 비교

이지하(Lee Jeeha),이상진(Lee Sang-Jin) 한국철도학회 2008 한국철도학회 학술발표대회논문집 Vol.- No.-

Track geometry consists of tangent and curved lines, which caused undesirable changes in initial track geometry by traffic loads. The bigger the changes are, the worse the riding comfort and running stability of train. This is so-called track irregularity and is the most important quality parameters of ballasted track. To be able to objectively assess track irregularity, track geometry should be able to be measured. Practically, railway companies use moving chord method, this method determine versine values via a chord. The versine is the vertical distance to curve measured in the middle of the chord. This type of method measures only versine of track irregularity curve by transfer function from specific property of measuring tool. In this report , review the characteristics of two types of measuring tools by comparing the measurements. The one is GRP-1000 system, optical surveying system with Total station and lazar prism trolly. This calculates track geometry by surveying absolute coordinates of two points each on both rail heads. The other is Trackmaster, measures versine with 2m of chord length.

계절변화가 고속선 궤도품질에 미치는 영향

강태구(Tae-Ku Kang),윤경민(Kyung-Min Yun),최일윤(Il-Yoon Choi),임남형(Nam-Hyung Lim) 한국철도학회 2013 한국철도학회 학술발표대회논문집 Vol.2013 No.11

경부고속철도 1단계 구간은 장대터널 3개소를 제외하고 모두 자갈도상궤도로 건설되었다. 고속열차의 주행과 자갈도상궤도의 특성으로 인하여 개통 초기부터 유지보수 비용이 발생하고 있다. 특히 자갈궤도는 다른 환경적인 영향도 많이 받으며, 잦은 궤도틀림이 발생하여 이로 인한 추가적인 유지보수가 필요하다. 본 논문에서는 궤도틀림에 영향을 미치는 환경요인을 분석하는 기초연구로써 계절변화에 따른 궤도품질 변화를 살펴보았다. The ballast track was constructed in full operation line excpet of 3 long tunnels in Gyeongbu - high speed railway 1st stage section. Due to the characteristics of operation of vehicle and ballast track, the track maintenance cost has been disbursed from beginning of the opening. Especially, the ballast track is considerably influenced by other environmental effects and requires additional maintenance owing to the occurrence of the frequent track irregularity. In this study, the variation of track quality was observed according to seasonal variation as a basic research for analyzing the effect of environmental factor on track irregularity.

On effects of rail fastener failure on vehicle/track interactions

Lei Xu,Jianmin Gao,Wanming Zhai 국제구조공학회 2017 Structural Engineering and Mechanics, An Int'l Jou Vol.63 No.5

Rail support failure is inevitably subjected to track geometric deformations. Due to the randomness and evolvements of track irregularities, it is naturally a hard work to grasp the trajectories of dynamic responses of railway systems. This work studies the influence of rail fastener failure on dynamic behaviours of wheel/rail interactions and the railway tracks by jointly considering the effects of track random irregularities. The failure of rail fastener is simulated by setting the stiffness and damping of rail fasteners to be zeroes in the compiled vehicle-track coupled model. While track random irregularities will be transformed from the PSD functions using a developed probabilistic method. The novelty of this work lays on providing a method to completely reveal the possible responses of railway systems under jointly excitation of track random irregularities and rail support failure. The numerical results show that rail fastener failure has a great influence on both the wheel/rail interactions and the track vibrations if the number of rail fastener failure is over three. Besides, the full views of time-dependent amplitudes and probabilities of dynamic indices can be clearly presented against different failing status.

현정시법을 이용한 자기부상열차 선로용 궤도틀림 계측장치 개발

임지훈(Jihoon Lim),공부성(Busung Kong),김기정(Ki-Jung Kim),한형석(Hyung-Suk Han) 한국철도학회 2013 한국철도학회 학술발표대회논문집 Vol.2013 No.11

자기부상열차의 궤도는 차량이 궤도 위를 부상하여 주행하는 형태이기 때문에 차륜이 레일 위를 굴러가는 일반철도와 궤도 단면형상이 다르다. 따라서 일반철도에서 사용하는 현정시법을 이용한 궤도틀림 계측장치는 자기부상열차의 궤도 특성을 반영하지 못하여 궤도틀림 기준과 정확도를 만족하지 못한다. 본 연구에서는 자기부상열차 궤도의 단면형상을 분석하여 측정기준면을 선정하고 현정시법을 이용한 궤도틀림 계측장치를 고안하였다. 본 장치는 사용성과 정확성을 중점적으로 고려하였으며, 수평/수직 틀림뿐만 아니라, 궤간, 레일 상하단차 및 평면성 틀림도 계측할 수 있도록 추가적인 장치도 제안하였다. 개발된 장치는 기계연구원 시험선에 대해 시범계측을 수행하고 사용성을 검증하였다. In Magnetic Levitation Train(Maglev),cross section of track is different from common track running on rail surface, because Maglev vehicle is running upon track levitated. Therefore the measuring device for track irregularities using in common tracks cannot satisfy the accuracy of criteria for track irregularities for Maglev. In this study, the cross section of Maglev track is analyzed to find the measuring point which can describe the track precisely and designed new measuring device by String Survey Method. The device is focused on the usability and accuracy and can measure not only horizontal and vertical but also top-bottom irregularities and torsion of track.