한국철도학회:학술대회논문집 (Proceedings of the KSR Conference) (Proceedings of the KSR Conference)
한국철도학회 (The Korean Society for Railway)
- 반년간
과학기술표준분류
- 기계 > 자동차/철도차량
- 건설/교통 > 철도교통기술
한국철도학회 2001년도 춘계학술대회 논문집
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The aim of tins study is to compare the travel time of urban railway with that of arterial roads in the Seoul metropolitan area, focusing on the five main railways and arterials - Ilsan, Bundang, Kwacheon, Kyoungwon, and Kyoungin in order to make suggestions about improvements of railways. We found that the travel times of railways and arterials are about one and a half hour and an hour respectively, also the ratio of railway travel time to arterial travel time is 1.34 at peak and 1.58 at off-peak. We conclude that the competitiveness of the railroads is lower than the arterials. It will be necessary that we research the ways to improve the service of railways and investment ranking among the five main railways.
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Despite of the introduction some sorts of the contract and the bid method like CM(Construction management) that will be efficient to manage the construction project. Korean agencies limit to control project management to do large public constructions. In the case of Taiwan, THSRC is apply J/V system in the public construction project, they are accomplishing that expend optimal the cost and save the construction time. To success J/V it has two factors, one is risk management and another is sharing information of construction project. Therefore, we will study to introduce J/V system to our construction project.
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THSRC uses the self-certification system for its high-speed rail construction. The self-certification system takes advantages of obtaining good qualify in project and communicating well between contractors and QA/QC organization. But one should understand ISO 9000s and the self-certification system of contractors in advance and contractors try to control Quality of construction spontaneously. Actually, construction progress is slowed down because of increased QA/QC works. For adapting this system in domestic construction, it is need to understand ISO 9000s and the self-certification system.
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Although the transferring is one of the most important factors in urban railways, there is very little analytic research in the transfer-related field. This paper analyses the transfer rate of urban railways in the Seoul Metropolitan Area and the actual passenger boardings and alightings at transfer stations using the AFC(Automatic Fare Collector) O/D data collected doling Sep. 2000. According to the results of this study the transfer rate is 0.657, which is calculated from the transfer hoardings/initial boardings. And the actual ridership of Subway Line 2 and Line 5 are different from the data which was provided by the AFC.
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To account for uncertainties involved in an economic analysis of project, sensitivity analysis are usually being done in Korea. Though useful for policy analysis, but it larks explicit consideration of probability of occurring certain events considered in the sensitivity analysis. Risk analysis otherwise can explicitly account for the probability of certain event which has dire impact on project viability, such as cost, discount rate, and size of benefit. This paper reports experience of applying risk analysis method for economic evaluation of railroad investment. Probability distribution of event has paramount impact on the risk analysis results, while not many prior researches dealt with these issues. Probability distribution of rolling stock cost and operating cost, in addition to those cost variables, are developed considering railway demand in this study. Case study results are reported. Issues in applying risk analysis are reported in addition to further research direction.
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ㆍ수도권 철도는 우리나라의 경제성장과 함께 증가하는 교통처리 대책으로 1974년 8월 15일 서울지하철 1호선과 함께 경인선 서울∼인천간, 경부선 서울∼수원간, 경원선 용산∼청량리∼성북간을 복선 전철화 하여 도시철도로 전환, 이에 따라 수도권 위성도시의 발전과 인구 폭증으로 안산, 산본, 평촌, 분당, 일산 등 신도시를 개발하고 교통난 해소를 위해 서울지하철은 1호선에서 9호선가지 건설중이며, 수도권 철도는 경부선 영등포∼천안간 2복선전철과 안산선, 분당선, 일산선, 경의선, 경원선, 중앙선, 경춘선, 용산선, 신공항선 등 복선전철화와 경부고속철도 등 수송능력 증강을 위해 건설하고 있다. (중략)
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Many changes in the railway environment has directly affected to the railway company. To cope immediately with the influence of environment and to promote productivity, the railway company has to introduce an efficient train operation system and related core technologies. The railway system is composed or large-scale infrastructures ann high-cost trains. Simulation method is one or core technologies and also is efficient tool for planning and analyzing this kind of complex system. The purpose of this research is to develop multi-train traffic simulator considering high-speed train for GyongBu-Line. To achieve this objective, the elements of railway system was analyzed, and as a result, a data structure modeling for the railway system such as rail-Tine infrastructure, rain, timetable and operational route is presented. The developed simulator is composed of three major part : input-module, main-module, and output module. The concept and brief explanation of each module will be treated.
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Most payments in domestic construction are issued in lumpsum unit price contracts according to the completed construction rate. This method generates problems in losing time and increased costs for the owner and contactor. In overseas projects, payments are issued in accordance to completed milestones. The milestones themselves base on the original schedule and allow effective schedule management on the tasks. In domestic construction, however, introduction of milestone payments requires enhanced management capability of owners and contractors. Hence, this study investigating how to activate schedule management devices to analyze progress payments in domestic construction.
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In this paper we present a nonlinear programming model for the solution of the train seat capacity distribution problem (TSCDP) with a numerical example. The TSCDP model finds the optimal capacity distribution methods which minimize the sum of the differences between the demands and the seat capacities. Also the TSCDP provides the information on the degree of the discrepancy between the demand and the seat capacities. One can use the TSCDP model as a tool for planning train seat capacity planning.
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The purposes of this primary study are the selection of rail station and train operation management techniques for express-rail operation service at the convectional railway electrification. For these analyses, we used the KNR statistics and KROIS data of rail stations and train users by rail line. Therefore, we chose the important stations for express-rail operation of Kyongbu conventional rail line (esp. Seoul-Jochiwon section) through the rail transportation demand. and then, suggested primary operational management plan thorough the effects analyses of decreasing total travel time and increasing transportation demand by train speed-up. This study has some bounds and limits for proceeding, as it does, we excluded as followings: the conditionals of fate system, headways and train diagram, economic/financial analysis and technological assessment, and other railway technological infrastructures and a certain railcar specification, etc. . We propose to enlarge this study into a feasibility study of express or skip-stop operation service and compatible vehicle system decision considering with the best possible investment rail line, furthermore. in front of Kyongbu (Seoul-Busan) high-speed rail open in 2004, we have to try to progress the efficiencies of railway operation applying various train operation management plan.
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Rail crossings are major accident-prone areas. Higher traffic volume, frequent rail operation, increased train speed all contribute to increased accident rate and severity In Korea efforts are being made to upgrade currently at-grade rail crossings to grade crossings. There is, however, no quantified analysis measures to analyse the impact of rail grade crossing, thus make it difficult to prioritize different projects under the budget constraints. Projects are selected based on the negotiation between Korea National Railway(KNR) and local governments. To shed light on the development effort for Korean procedure, GradeDec 2000 program of Federal Railroad Adminstration(FRA) was applied for Korean context. Case study involving three rail crossing was ca]lied out, and results are analyzed. Research efforts which need further attention are identified, research direction is analyzed considering local procedure, and issues in the application of the procedures are discussed in detail.
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If the Seoul-Pusan high-speed rail project is able to open its revenue service in 2004, Korea will be the fifth country with an HSR system in the world. And, it will be recorded as a major milestone in the transportation history of Korea. But, Government regulated railroad fare because railroad fare increase can bring negative influences to CPI(Consumer Price Index). Consequently, Korea National Railroad cannot afford to operate railroad independently under current railroad fare system. In this paper, we studied the railroad fare system under implementation and its influences to CPI. And then we proposed that railroad fare must be decided by competition with other transportation modes and based on the demand variance by introducing YMS(Yield Management System).
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This report was studied about speed-up for main line of KNR(Korea National Railroad) by High Speed Train. The maximum speed of Kyun-Pu line was recorded a 140km/h by Saemaul train in 1985 and the average speed its is a 107km/h now. For operation KTX Kyun-Pu High Speed Train and G7 Korea High Speed Train in KNR line, this report was studied about operation status of High Speed Train in advanced countries, operation situation of train in KNR line and plan of speed-up for main line.
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As of these, the exterior design of the public transportation systems, especially electric multiple, tends to mimic advanced country's design rather than design of car shape reflecting cultural and spiritual background. However, in the new transportation system, the design which satisfies the transportation demand must be changed into the design which creates transportation demand. In this respect, this research focuses on the factor's embodiment which is perceived by Korean passenger sympathetic to cultural and spiritual needs. The results of this research are Korean AGT design on rubber tire AGT, steel wheel AGT, LM AGT system and environmental design related to AGT systems.
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Numerical simulation is conducted to clarify the heat transfer and fluid flow characteristics of brake shoe for freight car. High order up-wind scheme for governing equations, k-epsilon turbulent model and SIMPLEC algorithm based on finite volume method are used to solve the physical shoe model. The governing equations are solved by TDMA(Tri-Diagonal Matrix Algorithm) with line-by-line method and block correction. From the results of simulation, the characteristics of cooling pattern is strongly affected by the velocity of train and the material of shoe. The face lift of shoe affects on the temperature distribution of rear surface of shoe as well as the front surface of that. Due to the grooves in shoe, it will be expected to cool the frictional heat and result in the reduction of maintenance efforts.
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This paper studies on the user-interface design elements for the vehicle interior layout of the Korean AGT(Automated Guideway Transit). These are based on the cultural environment and space consciousness of both ethnic and class differences. This means human- oriented interface design. In order to apply the user-interface design, it is necessary to find the examples of lightrail at the foreign country, and research and analyze their design trend. Then try to combine into a concept of user interface design and interior layout. This study will be expected to apply the Korean AGT as a guide.
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Modern people stay at indoor places about 90% of a day. Radon-222 is a gas produced radioactive decay of the element radium. And, radon is one of the major indoor air pollutants moves into the underground space through various routes and is considered to cause lung c hurting the lung tissues, In this study, we measured the subway radon level at 9 stations o According to test results, we can figure out the concentration of radon by lines, times, and m points. So, it was found that ventilation conditions are the most important factors in the su quality. Finally, we suggested effective and economic management methods of air pollution subway.
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Dynamic behavior of high speed train is very important because the high speed train should be safe and satisfied with the ride comfort. An eddy current brake system is mounted on trailer bogie and wheelset. The eddy current braking force longitudinally exerts on the articulated trailer bogie and the attraction force vertically exerts on the wheelset. Because a frame of eddy current brake system is flexible, these forces generate the vertical vibration at middle point of the frame. Also, the vibration change the vertical clearance between an electromagnet and top of rail which affect the magnitude of braking and attracting forces. Therefore, the dynamic behavior of the eddy current braking system must be predicted for design the dynamic characteristic of its mounting system when normally operate on rail which have irregularity. Vampire program is used for Prediction of the dynamic behavior of an eddy current braking system.
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In order to evaluate the sound transmission loss of a structure, a large reverberation room described by ISO is generally used. ISO test method is however for architectural structures, which is not properly implemented for small mechanical structures, such as rolling stocks. In this paper, evaluation procedure for railway vehicle structures has been proposed.
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There are many EMU lines in korea. But only one type has been applied to passenger side door. This type is so called "Pocket sliding type". This type has some week points. To begin with, it is not good for decreasing the noisy form the outside of carbody. And the second time, if some obstacles are put between sliding door, only driver can operate re-open door switch manually ill driver's cab. This type is so dangerous for passengers. So many people want to the new door type that have no defect. KRRI joined forces with ANT corporation for pneumatic plug door system. This type will be good for decreasing the noisy, passenger′s safe. The project was started at the last year on November and will be finished on June, this year In this paper, we will deal with the role of cylinder, planetary gear, door control unit, dynamic mechanism, and the report of FEM, type test. This paper will contribute to tile electric motor control plug door system.
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Since plug type passenger door has two motion modes, power transmission unit must be capable of plug-in or plug-out, and sliding mode. Complex planetary gear train is proposed, which is composed of two 2K-H, I type planetary gear units. For the proposed complex planetary gear train, ranges of addendum modification coefficients which would not lead to interferences is analyzed, and optimal addendum modification coefficients among these ranges which generate the maximum efficiency are presented. Based on the interference, efficiency and torque ratio analysis results, complex planetary new train is designed and manufactured.
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So many springs in the rail road trains have been degeaded by the long time operation. Specially vibrations makes worse the condition of the springs. The performance evaluation technique for the rail road spring was developed. Using integrated handy tools using hydraulic systems, LVDT, and related software, On-line evaluation is possible to check the system integrity.
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A chevron rubber spring is used in primary suspension system for rail vehicle. The chevron spring has function which support the load carried and reduce vibration and noise in operation of rail vehicle. The computer simulation using the non-linear finite element analysis program MARC executed to predict and evaluate the load capacity and stiffness for tile chevron spring. The appropriate shape and material properties are proposed to adjust the required characteristics of chevron spring in the three modes of flexibility. Also, several samples of chevron spring are manufactured and experimented. It is shown that the predicted values agree well tile results obtained from experiments.
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In this study, the carbody design of the rubber tired AGT(Automated Guide-way Transit System) under development by KRRI was numerically analysed to evaluate its structural strength according to the standard specifications for Korean LRT (Light Rail Transit). The numerical results showed that the detail design of the carbody was strong enough to satisfy the specifications with respect to the axial compression strength, the vertical strength and the vertical stiffness(natural frequency). However, the carbody design had some problems on the fatigue strength by twist loadings. So, it was recommended that the carbody design should be modified to improve the twisting strength by reinforcing the front end structures.
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In the standard specifications for the urban EMU(Electric Multiple Unit) train, there are several items to ensure safety against accidents. The 21th -23th items have much relation with the crashworthiness of the urban EMU train. In this study, the rubber- tired AGT(Automated Guide-way Transit System) under development by KRRI is numerically evaluated in a crashworthy point of view by applying the above crashworthiness items. The numerical results show the detail design of the AGT satisfies the 22th and 23th items. But the design is recommended to adopt mechanical fuses to reduce the impact accelerations with respect to the 21th item.
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Revision and establish of KS(Korean Standards) is currently actively discussed. It is just the time for a new world class standards under the new system with WTO(World Trade Organization). This paper is a part of "Researchs on the Standards in Railway rolling stock Field", as one of KS establish projects. The aim of this study is to define the requirements of railway rolling stock-designs, manufacture, and test methods for automatic complex coupler. In the former KS, there is no items matched with this purpose. Therefore a new part of KS is proposed.
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Recently, it has been trending toward speed-up not only in the passenger car but in the freight cu. In this study, we thus performed stress analysis for the carbody for high speed container freight car in use and field test of the freight car in Gyungbu-line so that we may utilize the results as a design guide for speed-up hereafter- Five vertical loading conditions due to dynamic effect and the weight of the carbody and the container applied to locking devices of the carbody and its results are compared with that of a test, As a result, we found that there is need to complement the strength of the carbody in some measure when speed up the present freight car.
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Barber bogie and Y25 bogie is the main bogie of freight car which is used in the Korean railway. In case of Barber bogie and a mixed formation tile maximum speed limit of empty car is 70 km/h and that of loaded car is 90 km/t and also it runs a speed of 110 km/h in time of an exclusive formation of Y25 bogie. The car named as high speed freight car at present is Y25 bogie which modeled on the Y25 bogie or Europe developed in 1993, Y25 bogie has no problem about the running capacity up to the speed of 110 km/h, but it works as limiting factors to tile increasing cost of maintenance and repair expenses which caused by repair of bogie and the cost of materials. This study is going to describe the contents examined by analysis and tests, aimed at being used as an index of plan in the future through the strength test of high speed freight car which is used now.
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This paper aims to verify the static strength of a KHST gangway structure including fixed ring and carrying ring according to tile load cases in the defined specification. The structure has been analyzed by the finite element method. Calculation carried out in tile fields of linearity and small deformation. The admissible limit is tile yield strength for the available materials. The analysis results show that Von-Mises stress at some locations of the structure is a little beyond the admissible limit. These results are successfully reflected on the adjusted design.
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For the structural integrity of large and complex structures such as railway vehicle, the in-field diagnosis of mechanical properties of the structures is needed, and especially, the mechanical characteristics of the weldment must be carefully evaluated. But, conventional standard testing methods having destructive procedures are not applicable to in-field assessment of mechanical property variations within weldment because they needs the limitations of specimen size and geometry. In this paper, to overcome this problems, the advanced indentation technique (AIS) is introduced for simple and non-destructive/in-field testing of weldment of industrial structures. This test measures indentation load-depth curve during indentation and analyzes the mechanical properties related to deformation and fracture. First of all, flow properties such as yield strength, tensile strength and work hardening index can be evaluated through the analysis of the deformation behavior beneath the spherical indenter. Additionally, case studies of advanced indentation techniques are introduced.
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The ductility of circular hollow reinforced concrete columns with one layer of longitudinal and spiral reinforcement placed near the outside face of the section and the steel tube placed on the inside face of the section is investigated. Such hollow sections are confined through the wall thickness since the steel tube is placed. The results of analytical moment-curvature analyses for such hollow sections are compared with those for the circular section with the sane diameter. In this study, moment-curvature analyses are conducted with Mandel's confined concrete stress-strain relationship in which the effect of confinement is to increase the compression strength and ultimate strain of concrete. The moment-curvature analyses confirmed that the ductility is primarily influenced on the ultimate strain. The variables influenced on the ultimate strain is the ratio and yield strength of confining reinforcement and the compression strength for confined concrete. From this ultimate strain - the transverse reinforcement ratio relationship, the transverse reinforcement ratio for circular hollow reinforced columns with confinement is proposed. The proposed transverse reinforcement ratio is confirmed by experimental results.
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This study investigated the shear stiffness of level of small strain with time effect. Time effect consists of rest time, loading rate of recent and current stress path. In addition, for the measurement of small strain, overconsolidated state was represented in a triaxial cell, and drained stress path tests were carried out. Test results show that the loading rate of recent stress path has no effects on the stiffness of very small strain, but the shear stiffness of level of small strain increases with it. Finally, the rest time and the loading rate of current stress path have the effects on the shear stiffness of initial and small strain.
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국내 고속철도 강합성 교량이 경부고속철도 8-2공구에서 처음으로 시공완료 되었다. 그동안 수년간에 걸쳐 고속철도 교량시공에도 불구하고 강합성 교량이 적용되지 못했던 것은 설계 기술적인 면과 더불어 재료 적인 면에서 국내여건이 성숙되지 못한 요인이 크다고 보여진다. 본 고에서는 기 설계된 PC BOX교량중 지형여건상 강합성교량이 적합한 교량구간을 제시하였다. 또한 강합성 교량의 설계기술적인면 중 특히 중요한 한국형 TGV차량의 동적 하중의 적용과 그에 따른 구조물 거동의 평가를 1@50 교량에 대한 8-2공구 사례를 통하여 논의하였다. 강합성 단면은 단순 2주형 주형거더(double I beam)이며 플랜지 두께는 최대 80-100mm가 적용되어졌다. 본 단면에 대한 HL차량하중등에 대한 정적해석을 통하여 관심이 되고 있는 플랜지등의 응력 검토결과를 보여주었다. 아울러 정적해석과 동적해석의 결과치를 비교하여 국내 시방서에 제시된 고속철도 HL차량하중에 대한 평가도 이루어졌다. (중략)
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Dynamic characteristics of catenary system for KTX Korean high-speed trains are investigated. A simulation program based on the finite element models of the catenary is developed. The influences of the various design parameters on the vibrational responses of the catenary are determined. The main design parameters include tension on the contact and messenger wires and the stiffness of the droppers connecting the two wires. The vibrational responses are primarily determined by the reflections of the propagating wave, and the dropper stiffness is found to be the dominant factor that influences overall dynamic characteristics of the catenary.
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In this study, a comparison between the structural design criteria for a catenary system with the maximum design speed of 100km/h and that of 300km/h was performed in order to establish that of 200km/h. According to the result, catenary design criteria for 300km/h operation is more conservative than that for 100km/h operation. This result shows that higher wind pressure and safety factor are adopted to catenary design for 300km/h operation. So, for the purpose of the economic structural design for catenary system, it is necessary to review the adoption possibility of catenary system for 100km/h operation first. In order to review the adoption possibility for catenary system for 100km/h operation, design criteria for 300km/h operation should be chosen for safer catenary structure.
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In order to evaluate the effect of impact load at support stiffness transition area, the field estimations are performed at the transition zone between earthwork and bridge on test operation of KTX. Due to differential settlement caused by the variations of track support stiffness, large impact forces are investigated. However, the measured values such as wheel load, rail stress, displacement and acceleration in the transition area shows that the stiffness changes in the transition area are not abrupt, and the stiffness in the infra track structure varies continuously. In this experimental study, the parameters influencing safety of transition area are not governed by partial or local stiffness because cumulative passing loads are not sufficient on test operation of KTX.
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A curved track needs balanced super elevation according to the speed of the passing train and it is limited by maximum allowable amount. Therefore, passing speed at high degree curved track has to be controlled below the limits. Accurate position of the Speed Limit Post(SLP), which shows allowable speed of curved track dose not regulated so design and line side maintenance engineer adopt the position differently, When the rate of cant deficiency is considered on transition-curved section, the SLP should be located at the beginning point of the transition curve so as to control the speed of passing train and it will increase ride quality to passenger.
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The lateral stability of curved continuous welded rail (CWR) is studied fur buckling prevention. This study includes the influences of vehicle induced loads on the thermal buckling behavior of straight and curved CWR tracks. quasi-static loads model is assumed to determine the uplift region, which occurs due to the vertical track deformation induced by wheel loads of vehicle. Parametric numerical analyses are performed to calculate the upper and lower critical buckling temperatures of CWR tracks. The parameters include track lateral resistance, track curvature, longitudinal stiffness, tie-ballast friction coefficient, axle load, truck center spacing, and the ratio of lateral to vertical vehicle load. This study provides a guideline for the improvement or stability for dynamic buckling in on tracks.
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The railroad under operation has very sharp curves and the state of ballast is somewhat deteriorated due to the traffic loads, which put some constraints in converting the conventional rails into CWR. In making CWR, the determination whether the ballast has sufficient capacity for resisting buckling must be made, quantitatively and qualitatively, and schemes to guarantee the required lateral resistance of ballast should be proposed. In this study, using the in-situ investigated data, the probability of buckling of CWR is given for several installation temperatures for CWR. The effect of tamping, DTS, and sleeper spacing are taken into account. The buckling probability is given as a function of curvature and installation temperature of CWR and works used to increase the ballast resistance capacity after tamping, i.e., DTS and reduction of sleeper sparing.
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The CWR, when installed on the bridge, may introduce extra responses in displacement, stress etc. due to the expansion of bridge girders. To release these responses, a special concern must be put on the CWR on bridges, especially for the long span bridges. Since the risk of derailment of vehicle due to buckling or breakout of the rails on bridges is of importance, the establishment of appropriate guidelines to check the performance of CWR on bridges is crucial for safe operation of train. In this study, using the program CWRAP, specialized for response of rails on bridges, several schemes for constructing CWR on bridges are suggested. In audition, a special concern is given to the bridge with sharp curve which is vulnerable to buckling due to temperature loads.
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Railway signaling safety system organizes equipments and facilities of railway, increases transport efficiency and assures safe operation of railway. In the early days of signaling system railway managers made sure of safety by using relay logic technology based on fail-safe concept. But the development result of computer and science having been introduced to railway industry, railway signaling equipments begin to be operated through micro electronic control system. Accordingly high speed and high density operation of train became possible. Software reliability and safety technology that controls important systems of railway was highlighted. In the middle of 1990s the standard or guideline of railway reliability and safety were studied and established, and are being reviewing in Europe, Japan etc. Our reliability and safety technology have depended largely on foreign countries. In this study we performed a basic study about the reliability of software that controls the railway signaling system.
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This paper proposes the system to describe the data transmission methods using the simply frequency transmission methods between a railway track and the train. This system can control the railway signals through the ABS or ATS system located in the train and stations, having the frequency about 433.92 MHz. It shows the advanced system to send a lot of data through the microprocessor installed in a transmitter and transmitter-receiver at the train and railway.
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This paper presents development of the program which calculates the electric quantities such as current, voltage at each element of railway electrification system in static state. The purpose of this program is to estimate the adequacy of railway electrification system through simulations. And it contributes the estimations for optimal railway electrification system by calculating the maximum current and voltage. The simulation program is coded through GUI(Graphic User Interface) technique for user to operate easily.
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This paper presents a concept design of detail design software for high speed catenary system. In this software, M.D.(mounting diagram) can be peformed and parts D/B can be also managed. french one, used in Kyung-bu high-speed line, is not good at user's interface, and the source code is not opened. So, it is impossible to use it in the different environment and catenary system. Through this program, automation of detail design and user's convenience can be derived.
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In this paper, we apply NHPP model example to s/w process in order to get to know s/w reliability. The test is constructed by a test zig of commercial product loaded real embedded system s/w. It is established to s/w reliability prediction and estimation of real-time embedded system s/w. It is computed the prediction value of cumulative failures, the failure intensity, the reliability and the estimation value of MTTF, Failure Rate. To the more realization of high reliability in the real-time embedded system s/w, if the embedded system s/w is ensured to the test coverage and constructed to stable s/w process & operating system, we can improve the performance and the reliability characteristic of the real-time embedded system s/w.
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The conventional SCADA adopted for the electric railway has the mere function of controlling and monitoring the hardware itself. Lack of the functions necessary far the fault prevention and the system recovery requires the operators to depend on their intuition and experience. To make up far these shortcomings of the conventional SCADA, PIS(Power Information System) visually offers integrated information for the optimal operation of the power system by manipulating the raw data acquired from the SCADA. In this paper we have studied the variety of information and its feasibility that can be offered individually by PIS.
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It was estimated that the anti-vibration measures at the source location of railroad are the most active and effective ones. Among CWR(Continuously Welded Rail), elastic rail fastener, floating slab, ballast mat, under sleeper pad, etc. like these various kinds of measures in the source, under sleeper pad as an anti-vibration measure was constructed at the railroad track supporting structures in the Jeon-la Line. In this study, through the field measurement of vibration at the railroad track supporting structures and nearby the ground, the vibration reduction effect of under sleeper pad were evaluated by insertion loss. As a result, vibration reduction effects were 5.0∼12.5㏈ on the concrete slab of the bridge, 3.9∼7.5㏈ on the ground nearby the bridge respectively.
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Generally, countermeasures for the train-induced vibration are divided into the measures at the source, propagation path and receiving object. Among these measures the countermeasure at the source location is the most active and effective one in the field of railroad. In this study, the effectiveness of each anti-vibration measures at the track(source location) such as elastic rail fastener, ballast mat were evaluated through the comparison of acceleration level, insertion loss at the installed locations of each measures. As result of field measurement of vibration at the railroad track supporting structures and on the ground nearby the structures, elastic rail fastener showed vibration reduction effect of 4.5 ∼7.3㏈ on the concrete slab, 1.6∼3.7㏈ on the ground with the train operation speed of 80km/hr. In the case of ballast mat, the vibration reduction effect at the concrete slab and on the ground were 11.9∼13.3㏈ and 6.1∼7.6㏈, respectively.
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In many countries the slab track of railroads is mostly applied on the railroad bridges and tunnels, however it hasn't been constructed in the tunnel in Korea. Presently the Korea high speed railway construction authority is planning to construct slab track in the tunnels to minimize the cost of maintenance and repair. In this study, dynamic characteristics of the railroad roadbed which was constructed using crushed stones obtained from tunnel construction was investigated through the field investigation, real scale model test and numerical analysis. As a conclusion, the roadbeds built with the crushed stones produced at the tunneling site satisfy the requirement of roadbed in terms of displacement and earth pressure for the slab track in tile tunnel.
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This paper shows the general description on the characteristic of civil structure for a automated guide way transit(AGT) system. There are three kind of AGT system; rubber tired AGT, steel wheel AGT and LIM AGT; for this paper.
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State of the art and current issues related with the RC and PSC structure system for the German magnetic levitation train were investigated. The German magnetic levitation train adopted a new kind of a structure to enable high-speed transportation, which allows the use of the space over a ground. The loading from Transrapid is light-weight compared with a regular train due to load distribution to a supporting structure. Therefore, Transrapid is considered an economical and efficient transportation system, and is also an environmentaly-sustainable structure, In this paper, the structural design and construction technology specific to a magnetic levitation train were discussed, and structural considerations related with an actual operation of the train were pointed out. In addition, the future research area of a magnetic levitation train was proposed.
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Out of 412km long Kyung-bu high-speed railway, 302km was designed in tile form of either bridges or tunnels. Most of bridges were designed to be prestressed concrete box girder type. The precast span method was selected because of good quality of bridge section secured by factory manufacturing, fast construction speed, low construction cost with mechanized construction and the safety fur field workers. The precast span method has been mainly utilized in bridges consisted of repeated simple spans. However, we applied the precast span method to continuous bridge for high-speed railway Since it was the first attempt to apply ate precast span method to a continuous bridge for high-speed railway, many design and construction details were studied and implemented in the construction. Design and construction processes of a continuous bridge construction using tile precast span mettled are briefly described in this paper.
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Hardening agent has been the traditional material for surface soil stabilization of soft ground. The aim of this study if to determine optimal mixture ratio of hardening agent in accordance with the required design specifications. Hardening agent consists of fly ash, gypsum, slag and cement for the ettringite hydrates and if effective for early stabilization of unconsolidated soil. The raw ground material is the clay that is widely found here and there in Korea. In this study, preliminary tests were performed to get optimal mixture ratio of stabilizer ingredient and marine clay in Jinhae was used to get physical and chemical properties. Laboratory tests of 50 stabilized soils were performed to get optimal mixture ratio for 16-stabilizer materials of 6 types, and mixture ratio of stabilizer ingredient and marine clay was determined.
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The object of this study is to determine the application of friction and ground stress type CGP(Compaction Grouting Pack)-anchor in retaining wall construction on the soft ground by executing in the fill deposit with abandoned coal. In this study the effect of CGP-anchors as retaining wall anchor on the soft ground anchor was evaluated through measuring displacement according to tensile strength by acting tensile strength after equipping CGP-anchors. From the field tests results, CGP-anchor was determined to be considerably effective as retaining wall anchor on the soft ground by showing that the maximum displacement was 60mm and the elastic displacement was within 50mm by 53ton tensile strength.
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현대건설(주)는 사업 주관사로서 해외 업체와 대만고속전철 턴키 공사를 2000 년 1 월에 공동으로 수주하였다. 고속전철의 총 연장 길이는 약 326 km 이며, 정거장 10 개소, Depot 및 야적장으로 구성되어 있다. 이번에 수주한 공구는 2 개의 연속된 공구 (C230, C240) 이며, 본 논문은 총 연장 23.6km 인 C230 공구에 대한 설계 과정을 수록하였다. C230 공구는 NATM 터널 (6.2km), Cut-and-Cover 터널 (0.5km), 교량 (7.8km) 및 토공 구간 (9.1km)으로 구성되어 있다. 전 구간의 지반조건은 "매우" 취약한 매질로 구성되어 있으며, 층리나 절리는 거의 발달되어 있지 않다. 따라서 화약발파에 의한 터널 굴착은 기계식 굴착 (Back-hoe Excavation) 방법에 비하여 현실성이 없는 것으로 분석되었다. 취약한 지반에서 계측 결과를 기준으로 굴착 공간을 안전하게 유지할 수 있는 NATM 보강 설계가 현지 암반조건에 가장 이상적인 방법으로 제시되었다. 특히, NAT설계는 대형 아파트 지역과 파쇄대 및 지하수 침투 예상지역을 통과하기 위하여 계측에 의한 Feed-back 과정을 탄력적으로 적용하도록 계획하였다.
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Rockfall has long been a serious problem, especially derailment of train running on the track in mountainous regions. The purpose of this study is to suggest the reasonable items of check and evaluation to railroad rock slopes for safe maintenance and management of rockfall-worried railroad sites. Therefore, main and sub items were extracted from the survey of foreign and other authorities' cases and evaluation table (temporary) composed of items classified by important degree was suggested. To evaluate the availability and reasonability of items, statistical analysis based on field investigation namely SMR(Slope Mass Rating) and explanation values was carried.
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In Korea, collapse of railway slopes is frequently occurred due to tycoon or heavy rainfall doling rainy season and has been made personal and social damage greatly. In order to evaluate the stability of railway slopes under rainfall, explanatory variables and subordinate variables were selected for multivariate analysis. The sites which failure had occurred due to rainfall were investigated and critical rainfall was defined by the case that had high value of correlation factor after multivariate analyses for 121 cases had been executed. The maximum hourly rainfall during 24 hours before failure caused the collapse of railway embankment and the 0.3 square value of maximum hourly rainfall during 24 hours before failure caused the collapse of railway cut-slope, From the application to collapse examples, it is judged that critical rainfall curve will be used to estimate the stability of slopes.
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This paper shows the reduction effect of tile earthquake-induced liquefaction potential of soils that improved by Vibro-Replacement Stone Columns. The Vibro-Replacement Stone Columns method transforms soft cohesive soils into a composite mass of compacted granular or crushed stone columns by using vibrating equipment and water jets. This study investigated and analyzed the behavior of the stone columns and composite ground using the results of in situ test and measurement at the job-site. This paper shows the evaluation of the earthquake-induced liquefaction potential of soils using in situ test. There are different types of in situ test used in the evaluation the liquefaction potential. In the particular study the Standard penetration test, and Cone penetration test were used. The N value of Standard Penetration test has been used all over for a very long time. The evaluation of the liquefaction of soil was performed using the worldwide renewed Cone penetration test
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The purpose of this study was to evaluate shear parameters on cutting slope of weathered granite soils by using small dynamic cone penetration test on the very moment of its cutting. The results were : On the relations among N
$\_$ c/, Li, and CEC, the condition of Li>6%, CEC>14(meq/100g) corresponds to that of N$\_$ c/ values of 2∼30, and 3<CEC<14(meq/100g) to N$\_$ c/=30∼50. Comparing the smallest penetration depth from two small dynamic cone penetration tests done at 5m below from the top of the slope on April 15th, October 31t. there was a l0cm difference. So we could find out the degree of weathering on the slope. And dividing the difference by 190 days (the whole testing time), we could know it's being weathered 0.052mm each day. The more N. value increases, the more shear parameters(internal friction angle ;$\phi$ , cohesion : c) increase at a standard pressure($\sigma$ >32㎪). So the condition of N$\_$ c/=2∼50 corresponds to that of$\phi$ =27∼50, c=12∼49㎪. From the above testing results, the N$\_$ c/ values more correspond to$\phi$ values than c values. In conclusion, this study suggests that on small dynamic cone penetration test a penetration boundary line of 5 centimeters is decided at around Li=4%, CEC=3(meq/100g) which is classified as a strong weathering soil. It also shows that as Li increases CEC increases as well, while N$\_$ c/ decreases. -
The Prefabricated Vertical Drain(PVD) method is most widely used technique to accelerate the consolidation process and to strengthen the weak clayey soil in situ. Uncertainty in the consolidation process via the Prefabricated Vertical Drain(PVD), and the effects of uncertainty on the design of PVDs, are investigated in this paper, Among the effect factors, the coefficient of horizontal(radial) consolidation, C
$\sub$ h/, is the most important and sensitivity analysis of the degree of consolidation with respect to the other effect factors are carried out. For the reliable determination of uncertain quantities, the laboratory and in-situ tests are carried out. Henceforth, probability analysis that take the uncertainty into account are executed and reliable design method is provided in practice.