Proceedings of the KSR Conference (한국철도학회:학술대회논문집)
The Korean Society for Railway
- Semi Annual
Domain
- Machinery > Vehicle/Rolling Stock
- Construction/Transportation > Railway Transportation Technology
2002.10b
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21세기 무한경쟁시대에 대비하여 국가산업의 경쟁력제고는 물론 지역의 균형발전을 위해 추진하고 있는 경부고속철도 건설사업은 2004년 4월 개통을 목표로 마무리 단계에 접어들었다. 경부고속철도 건설사업을 통하여 우수하고 완벽한 성능의 고속열차도입과 함께 첨단기술을 이전받아 기술수준을 향상시켰고 G7 연구개발 사업으로 시속 350Km급의 차세대 차량을 설계, 제작할수 있는 능력을 보유하게 되었다. 철도는 육로 교통수단과 달리 시스템적 특성이 매우 강하다. 즉 토목, 건축, 기계, 전기, 전자 등 각 분야의 균등한 기술발전을 도모하여야 철도선진국에 진입할 수 있으며 해외 진출이 가능하다. 사업 추진과정에서 습득한 각종 기술은 향후 건설사업의 독자적 추진을 가능케 하였으며, 철도차량의 제작사뿐만 아니라 부품업체가 해외시장을 개척할 수 있는 능력을 갖추어 철도 선진국으로 도약할 수 있는 기틀을 마련하였다.
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1969년 10월 개통된 일본의 토오카이도 신칸센은 세계최초의 고소철도로 당시만해도 세계를 놀라게 하였다. 그러나 일본의 고속철도의 개발은 2차대전을 일으킬수 있는 바탕이 된 기술자들의 패전후 업무었다는 점에서 패러다임의 변화를 알 수 있다. 그런데 이제 우리나라도 경부고속철도 개통을 앞두고 있어 이에 대한 많은 논란이 되고 있다. 이러한 점에서 앞으로 경부고속철도 착공이전과 착공이후에 논의된 이상의 토의가 필요한 것이 운영 문제라고 볼 수있다. 그래서 본 고는 일본의 최초의 고속철도인 토오카이도 신칸센의 개통에서 최근까지를 정리하여 향후 경부고속철도 개통을 앞두고 그 시사점을 알아보고자 한다. (중략)
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The Friction Brake Pad of High Speed Train is the most important parts in brake system, which is usually made of Cu-based Sintered friction material. This study has been carried out about the formulation effects of sintered friction material and made lots of sample brake pads. Then, we have done the performance test of the developed product by using full scale inertia Dynamo-meter. This performance test (braking speed 300km/h) was conducted as GEC Alsthom Standard test procedure and High Speed Brake Test (braking speed 350km/h) was done at "Poli" in Italy. The friction properties of this product was almost identical with the brake pad which is currently used to TGV. And the temperature of brake disk on braking speed 350Km/h was a little higher.
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This study presents the wheel wear measurement results of Saemaeul train running on the conventional line. The train set included three different cars which have different shape of wheel profile including KNR and KTX profile currently used in Saemaeul. Train set was operated on Seoul-Pusan line with fixed train set formation for commercial service. Wheel wear measurements were peformed periodically. Here, we describe some results.
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표준전동차는 1995 년 9 월부터 2001 년 12 월까지 수행된 도시철도차량 표준화 국산화사업의 일환으로 도시철도차량 표준화와 차량핵심장치의 국산화를 위해 개발되었으며, 한국의 표준이 되는 전동차이다. 도시철도차량의 표준사양, 성능시험기준, 품질인증기준, 안전기준, 정밀진단기준 등 제반 표준화기준에 의거하여 표준전동차가 설계, 제작되었으며, 수입에 의존하던 추진장치와 차량제어장치를 국산화하여 장착하였다. 제작된 핵심장치 및 표준전동차에 대해 구성품시험, 완성차시험, 본선시운전시험, 실용화를 위한 10 만 Km 내구도주행시험 등 각종 성능시험이 수행되었으며, 전동차 국산화율이 60%에서 95%로 향상되었다. 본 논문은 표준전동차의 개발경위, 핵심장치 국산화 내용, 각종 시험결과 등 전반적인 개발내용을 기술하고 있다.
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The operation of double deck train have increased in many countries such as Japan france, and the Netherlands as efficient, safe and convenient alternative transportation systems. Because of continuous concentration of population into Seoul metropolitan and serious traffic jam, the number of passengers using the commuter train have been increased rapidly. Considering these situations, we can find one of the solutions for heavy traffic problems through double deck trains. Stainless steel, and aluminum extruded panel are used to reduce the weight of double deck train. In this paper we compare the results of structural analysis of the double deck car body structures with Al extruded panels and stainless steel. We hope the results of this study may be used as basic guidelines in designing double deck trains in the future.
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The air spring is used in secondary suspension system for railway vehicle to reduce and absorb the vibration and noise. In this paper, the characteristics and durability test was conducted in laboratory by using servo hydraulic fatigue testing system to evaluate the reliability. And to guarantee the adaptation of this air spring, the ride comfort and air pressure variation were measured in train test. The experimental results show that the characteristics and durability of domestic development productions are obtained the good results and the stiffness of the air spring which had become 6 year over increased. Also, the dynamic characteristics of domestic and existing product agree well the results obtained.
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As the speed of rail transit is higher, it is very important to secure the safety and confidence of the braking device and in the point of view, by means of the rise of the temperature from the friction between the disk and pad which are the actual part of a braking system, the damage of brake disk is the main cause to lose the safety of braking device. Therefore, in this study, to predict the danger of a disk brake and to know its max. temperature in the train service the module of a temperature measurement by the non-contact method was developed.
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In recent years, due to the continuous concentration of population and sharp increment of commuters around Seoul metropolitan area, traffic jam has become one of severe problems along with housing in this area. In oder to solve the problem like the one mentioned above, several countries such as Japan, France and so on gradually operate double deck trains as efficient, reliable and comfortable mass transportation systems. However, the double deck train has weak points such as big cross sectional area and high mass center that cause unsafe vehicle running performances and interface problems between the vehicles and infrastructures. Therefore, prior to operate double deck trains on the existing lines, careful investigations should be performed. For these reasons, we have investigated foreign double deck trains and studied the technologies for a double deck train as an alternative way to carry heavy transportation efficiently and comfortably.
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As tilting train is the effective solution to provide faster passenger service on conventional railway lines without too costly modification of infrastructure, it is expected that tilting train will be put into service for Korean conventional Railway Lines. Very few passengers may suffer from motion sickness on conventional train and high speed train. But some sickness among passengers of tilting trains have been reported. Up to now, a standardized motion sickness index was mainly developed in the shipping domain. Therefore, there was a need for railway motion sickness index in order to predict and evaluate the motion sickness which is likely to be experienced by passengers. This paper is the preliminary investigation to propose the technical index related to motion sickness and nausea phenomena for the tilting train development and operation.
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This research aims to test the running stability of the developed bogie with maximum operating speed of 350km/h, which of Korea TGV was 300km/h. The running stability test has been executed in status of a dummy car with one developed bogie and one dummy bogie on the roller rig to embody similar operation condition. The test has been done in the two rail conditions, i.e. excitation and non-excitation, respectively. Running speed has been increased by the roller step by step. In consequence, the developed bogie was proven to be able to run upto 400 Km/h without any unstable point in the non-excitation. Vibration characteristics of carbody also was within the value specified on the UIC 515.
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Maglev is the vehicle which can run in levitated condition by the electro-magnets, and the vehicle can run without any contact condition. The vehicle is devided in two parts such as carbody and bogies, and the bogies are the driving device of the vehicle. There are many equipments in the bogie, and the frame endure many loads occurred in the operation of the vehicle. The bogie frame is designed and manufactured in the view of good safety and maintainability, and the engineers work to accomplish this purpose.
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In this study, the property against low velocity of the compesite material, which will be applied a rail vehicle, is shown using experiment and a finite element code. The property can be denoted the resistance of impact force, which is defined by maximum impact force over damage area. A damage propagation model is necessary to estimate accurately the impact property of a composite material through FEM code.
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철도차량의 주행장치는 비틀림 선로를 주행할 경우 윤중감소가 발생하게 되며 이 값은 모든 하중 조건 및 공기스프링의 충기/배기 상태에서 UIC/ORE 보고서에서 규정한 기준치 60% 이내를 준수하여야만 한다. 이 논문은 인도 DMRC 전동차를 대상으로 시험을 실시하여 DMRC 선로 중 최악의 조건에서 UIC / ORE 에서 규정하고 있는 차량의 윤중감소율( Wheel Off-loading)의 기준을 만족하는 지에 대한 평가한 것을 기술하였다.
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Studied in this paper was the kinematic envelope of the railway vehicle to calculate the lateral displacement using the multi-body dynamic simulation program (VAMPIRE) and the BASS 501. The lateral displacement of railway vehicle is occurred by the clearance between wheel flange and rail, the track irregularity, the property of each suspension of vehicle and the cant of track etc. The results of analysis shown that Vehicle is not interfere with subway platform in any conditions namely the tare and full load condition, the wheel wear condition and the stationary and running of vehicle.
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The weight saving that results from the substitution of aluminum alloy for steel may be used to provide reduced energy consumption and labor cost due to simplified manufacturing process and improved vehicle performance. Because of these advantages, foreign advanced rolling stock manufacturing companies have been using aluminum alloy for bodyshell manufacturing. In this research, the comparison between FE analysis and actual load test results is performed for aluminum extrusion bodyshell, which is manufactured by Rotem Company. And the results show that the aluminum carbody structure satisfies the strength and stiffness requirements. Commercial FE analysis code and specially designed test equipment are utilized for the structural analysis and the static load test of bodyshell respectively.
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Electric vehicle body has to be subjected to uniform load and requires auxiliary equipment such as air pipe and electric wire pipe. Especially, the cross beam supports the weight of passenger and electrical equipments. a lightweight vehicle body is salutary to save operating costs and fuel consumption. Therefore this study is to perform the size and the shape optimization of crossbeam fur electric vehicle using the method of topology optimization to introduce the concept of homogenization based on optimality criteria method which is efficient for the problem having the number of design variables and a few boundary condition. this provides the method to determine the optimum position and shape of circular hole in the cross beam and then can achieve the optimal design to reduce weight.
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This report is the result performed the structural analysis and the static and fatigue load test of bogie frame for the purpose of designing and verifying the bogie frame which satisfy the load condition required in the UIC code. This investigation is proposed the efficient draft of the design to satisfy the load condition required in the UIC code. And It is performed the structural analysis to evaluate the static strength and the fatigue life of the patient material and the welded part. Also, This is proposed the efficient draft of the test to satisfy the method of the static and fatigue test required in the UC code. And it is carried out the static and the fatigue load test to verify it. We can designed the bogie frame in compliance with UIC 515-4 and 615-4 code.
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The research was requested by Meridian Rail Corporation in United States. The Swing Motion Bogie can application by Korea style if synthesize study result of bogie strength evaluation, bogie dynamic characteristics analysis, actual test(maximum speed, derailment coefficient, lateral force, vertical force, vibration acceleration, steady state lateral acceleration) etc..
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The railroad is a means of large transportation which has many talents such as a safety and a regularity. That is a results from various confidential performance tests and evaluations of the system. The railroad system consist of various subsystems - vehicle, power supply, signal, communications, track structures, operations, etc. Among them, as an item of safety evaluation there is a measurement of wheel/rail force, so called a measurement of derailment coefficient. This is a very important item because a derailment of a train will bring about a big accident. Especially it is more inportant in high speed rail of which operation speed is over two times as fast as existing rail. In this paper, it is introduced to preprocess the wheelset for measuring wheel/rail force of high speed rail, such as to treat a measuring wheelset, its finite element analysis, adhesion of strain gauges and static load test.
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This paper contains the tension-tension and the tension-tension bearing fatigue characteristics of glass fabric/phenol composite laminates. The experimental results show that the bearing fatigue characteristics of the material is so excellent compared with the simple tension fatigue characteristics, that there are no needs of additional strengthening for mechanical joint parts when the parts are properly designed. The experimental data are also compared with the results of glass fabric/epoxy composite laminates.
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Recently, fundamental innovation for the improvement of Korean railway industry is proceeding with the vertical separation into infrastructure and operation, and the privatization of railway operation. And also, with the advent of an era of high-speed railway, starting of Korea Train Express (KTX) will give a great change to circumstances of railway industry. It requires that a railway safety regulation policy and accident survey system cope effectively with this restructuring of railway system. Under these great changes, safety must have the first priority, and the function of management and supervision on railway safety will be ten to the governments responsibility; In this paper, according to changes of railway safety management system, foreign states railway accident system and direction of korea railroad accident survey system will be also introduced.
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This paper is about the maintenance CALS system development and construction for the urban transit railway. The operation companies of urban transit railway are driving to construct the maintenance CALS system individually. So, there are concerned problems of duplication investment and waste of budget in the national aspect, inefficient CALS system construction, and etc. In order to resolve that, the KRRI is driving to development and construction of the standardized maintenance CALS system for the urban transit railway. This paper describes the result of basic design of the standardized maintenance CALS system using the CBD development method.
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This paper presents a Rotem's methodology for the establishment of train operation plan in Railway system. Train operation plan is the key prior plan to proceed the design of the civil and E&M relevant subsystem. But, due to the limitation of the environmental and project condition, common consensus to the key factors which make up the operation plan have not been accomplished. So, as a result of this comparative review for the general approaching method of train operation plan and application status of the major key factors being performed by Rotem, we will get the opportunities to improve the accuracy of the train operation plan.
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As the subway composed of rolling stock, power supply, signalling, infrastructure is complex system, the optimization through standardization is one of the most effective way to reduce the cost of construction and operation. However, the subway in Korea has been built and operated in different kinds of system. In this paper, review for standardization of urban transit in Korea is executed and presented direction to standardization.
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Volatile Organic Compounds(VOCs) contribute to the formation of ozone and PAN which are injurious to health through complex photochemical reactions. Growing consumption of fossil fuels results in significant emission of VOCs and other air pollutants into the atmosphere. This study was carried out to evaluate of Volatile Organic Compounds(VOCs) concentrations in Kumi industrial complex. Ambient air sampling was determined at five sites from August to September in 2002. The Volatile Organic Compounds samples were collected using the silicocan canisters, and were determined by GC/MS which connected preconcentrator system. The Kumi industrial complex of VOCs concentrations were generally similar with Yeochun's but some of VOCs concentrations of Kumi were higher than Yeochun industrial complex's. Also the industrial area was higher than downtown and residential district.
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As the delay of the Kyungbu High Speed Railroad, HST should use conventional line through Daegoo to Pusan until the new railroad build. High speed railroad noise is one of the main causes of environmental impact. Whenever HST on conventional railroad line is planned or a housing project near an existing railroad is proposed, an estimate of the relevant noise levels is usually required. For this, it is necessary to quantify those parameters that affect the railroad noise. This paper deals with an estimation of high speed railroad noise on conventional line.
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Ventilation system on passenger rooms should be designed for the health and comfort of the passengers. One of the main aim is to create an acceptable thermal environment without draught problems. The draught sensation increases when the air temperature decreases and the air velocity increases. Airflow in passenger rooms is turbulent. Lateral temperature and humidity gradients in the electric rolling stock have been studied. And, the difference in the mean temperatures measured at 0.7, 0.9, 1.2, 1.7 m above the floor. It has been found that temperature with large fluctuations caused more draught complains.
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In this study we reported the Smoke Density, the Toxicity, the Flame Spread Characteristics and the Oxygen Index of the FRP composite interior panels for raicars. Also investigated the test codes of the concerning items of other countries. We made some samples to the variance of resin types, surface finishing methods and panel shapes. It's not the really used ones but may help us effectively to guess the fire safety characteristics of railcars.
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Recently, many studies are performed according to increased interests about factory or room acoustics. In this study, the inside and environmental noise conditions of Diesel-locomotive load test building were investigated by multi-channel noise measurement system. In addition to this, the mitigation effects of environmental noise from this test building were analyzed using commercial software.
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We actually installed antibacterial air filter on the air intake route to air conditioner in passenger car and evaluated filters performance on antibacterial effect. And also, antibacterial effect was observed at whole are of filter media by zone of inhibition test. In the evaluation of antibacterial test, it was shown that the air filter has notably sufficient antibacterial efficiency against ordinary filter.
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ACSR of the catenary wires is corrosion degradation progressed by the effect of atmospheric pollution. ACSR which consists of galvanized steel stranded aluminum. The inside of Steel Reinforced is hot-dipped zinc coating steel wire and it takes charge of tension. If ACSR is exposed in atmosphere, the galvanic corrosion is occurred because it is contacted with aluminum. It is occurred the chemical reaction rapidly so that the local a defect is also occurred. If the catenary wires are exposed in atmosphere of pollution conditions, it may cause to reduce the mechanical strength by corrosion degradation and may cause to damage the wires by micro cracks. Accordingly, this study presents the effects of mechanical properties through the corrosion of ACSR.
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In case the fault occurs in railway high voltage power supply network, protective relaying system must selectively detect 1 wire ground fault of grounding or non-grounding system. And this study presents railway high voltage power supply system model using PSCAD/EMTDC Vet 3.08 for circuit analysis and fault studies. In this paper, we propose protection method of non-grounding system of railway high voltage power supply system. The result shows its usefulness.
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This paper presents general concept of DC switch gear(DCSWGR). Normally, DCSWGR consist of Digital protection unit(DPU), High Speed Circuit Breaker(HSCB), Disconnect Switch (DS), Programmable Logic Control(PLC), Auxiliary Relays and etc. Most of the components has its special characteristics and their interface between each others are various and complex. In this paper every constituent general design are preceded and interface between each component are examined. And also DCSWGR operation logic with logical diagram including interlock signal are introduced.
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1 적용범위와 배경 각종 전동차에서 발생하는 자계의 발생을 살펴보고, 객실에서의 시뮬레이션과 측정결과를 바탕으로 인공심장박동기 및 이식형제세동기를 장착한 승객의 안전을 자속밀도에 대한 국제적인 요구사항 및 검토결과와 비교하여 이들 기준치의 안전성여부를 상세히 고찰해 보고자 한다. (중략)
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In this paper, a regeneration inverter is proposed using 3-level inverter. Electric regeneration means regeneration brake in electric railway vehicles. Induction motors, generally used with railway vehicles, convert the electric energy to the movement energy when vehicle is running. When the vehicle stop, the induction motor convert the movement energy to the electric energy. Usually, this energy is used with another running vehicle in the same section. If there is no vehicle around when the regeneration is occurred, regeneration energy is consumed by heat energy with resistors. The proposed inverter is capable of reuse this regeneration energy in another place.
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This paper introduces the combined test results of the traction system for Korean High Speed Train. The main purpose of this combined test is to verify the performance of the traction system that is designed to operate up to Maximum 350Km/h speed. Various kinds of experiments are performed to prove total traction system performance and detailed waveforms are described.
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The conventional SCADA being used in the electric railway has the basic functions of remote controlling and system monitoring. Since the SCADA lacks the functions essential to the fault prevention and the system recovery, operators must depend on their intuition and experience to considerable extent. Visually integrated information offered by PIS contributes to the fast system recovery and the state judgment of the power system, and makes a novice be adapted for the operation easily. In this paper, we have studied the various functions and its feasibility that can be offered by PIS.
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Object of this paper are numerical and experimental evaluation of Korean Standard Train Loading(L-loading scheme) with respect to UIC's and real train loading, quantitative formulation of the real train types in South Korea. These objects are require to changing environment of train operation, for example, high density traffic and gradual train speed increase. For the reasonable repair, reinforcement and rehabilitation of existing railway infrastructures, statistical analysis of the loading effect during the long term experiment in conventional lines have to conduct. Statistical quantitative formulation of the loading case need to consistency numerical evaluation of the railway safety. Hereafter, those results will be core technical data for the economy enhancement of international line construction. Further, these results are using to make track maintenance criterions for transcontinental, speed up railway and revision of standard train leading diagram.
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Railway plate girder bridges have characteristics that are not show dominant frequency in dynamic response frequencies like obtained vertical acceleration on the bridge during the train passing because the train loading relatively bigger than the bridge self-weight. This paper experimentally confirmed in FFT result has various frequencies due to inherent characteristic of railway train loading. To establish classification of dynamic frequency range in railway bridge acceleration during the train passing, vibration frequencies result from experimental test are analyzed concerning actuation vibration factors. Factors are train velocity, train type, mass ratio of vehicle/bridge, stiffness of bridge, bridge/track and vehicle/track. From the result, it is proposed that the frequencty classfication table with corresponding factors. Using the proposed table to develop rehabilitation technique of the plate girder bridge, to expect vibration reduction and comfort enhancement of the railway plate girder bridge.
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A railway open deck plate girder bridge without ballast should support relatively heavier vehicle loads compared with its self-weight. For such a reason, actual dynamic response of the bridge is considerably differing with normal prediction because additional masses added from vehicle to a bridge have an effect on the dynamic characteristics of the bridge. These differences affect to the estimation of a natural frequency change that adopted for one of the evaluation technique of strength decrease, and these make trouble to the analysis of a natural frequency from the field test data that measured at the bridge subjected to a running vehicle. In this study, classification of mass participation ratio for each component of open deck plate girder bridge without ballast and the comparison according to the change of vibration characteristics for the case of subjected to a running vehicle were accomplished.
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KTX is going to directly operate on the existing plate girder bridges before the complete construction of new high-speed line. Also the speed and traffic volume is increased after electrification of conventional line. Then, it is necessary to check the dynamic behaviors of these bridges. Therefore, this paper reviews the dynamic behaviors of welded plate girder bridges designed by L-22, a standard load type of KNR. The span lengths of plate girder analyzed here are 6.6m, 9.7m, 12.9m, 16.0m, 19.2m, 22.3m, 25.4m and 31.1m. Using 2-D dynamic analysis, vertical deflection ratios of plate girder and maximum accelerations of car body are calculated. And the analytical results are compared with those of design criteria.
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Calibration of the health monitoring system is considered in this study. For this, brief introduction on the realtime monitoring system, installed in some of the Korea Highspeed Railway bridges, is made and specifications of the calibrators are outlined. Calibration method is next explained for each sensor and detailed procedures are illustrated. Calibration results will be published elsewhere and modification of the gauge factors will also be investigated in detail.
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The behavior of an opening and the performance of support system depend upon the load-deformation characteristics of ground and support as well as of the manner and of timing of support installation. The load-deformation characteristics of ground and support are derived by the interaction between ground and support. The interaction between ground and support is qualitatively illustrated by a ground response curve. The behavior of an opening and the performance of support system depend upon the load-deformation characteristics of ground and support as well as of the manner and of timing of support installation. The interaction between ground and support is qualitatively illustrated by a ground response curve. The convergence-confinement method don't need the basic assumptions for a mathematical model. Also This is applicable to general tunnel. Consequently the stability of tunnel must be qualitatively investigated by a ground response curve and quantitatively adjudged by a numerical analysis for the reasonable design of tunnel.
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A new damage identification technique using static displacement data is developed to assess the structural integrity of bridge structures. In the conventional damage assessment techniques using dynamic response, it is usually difficult to obtain a significant natural frequencies variation from the measured data because the natural frequencies variation is intrinsically not sensitive to the damage of a bridge. In this proposed identification method, the stiffness reduction of the bridges can be estimated using the static displacement data measured periodically and a specific loading test is not required. The static displacement data due to the dead load of the bridge structure can be measured by devices such as a laser displacement sensor. In this study, structural damage is represented by the reduction in the elastic modulus of the element. The damage factor of the element is introduced to estimate the stiffness reduction of the bridge under consideration. Finally, the proposed algorithm is verified using various numerical simulation and compared with other damage identification method. Also, the effect of noise and number of damaged elements on the identification are investigated. The results show that the proposed algorithm is efficient for damage identification of the bridges.
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Long term measurement data on the bridge response caused by moving loads are fundamental ingredient to the development or improvement of the new bridge design. In addition, proper establishment of the systematic analysis and diagnosis together with the maintenance system become the essential procedure to the effective repair/reinforcement/retrofit of not only the high speed but also the conventional railway bridges. Therefore, the real time health monitoring system on the important railway bridges should be enhancing the proper maintenance of the structures. The main objective of this study is, therefore, to develop a monitoring device including Weigh-In-Motion (WIM) function and the emphasis is place on the easy and economic installation of the developed system in the field condition.
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A dynamic characteristics of existing steel plate girder railway bridges without ballast were investigated from the finite element analysis. Span lengths, types of vehicle and running speeds are selected as parameters for analyses. For more exact analysis, it was adopted that 3-dimensional bridge models and wheel loads were produced by averaging field measured wheel loads of running vehicles at various speeds. Dynamic vertical deflections, dynamic amplification factors and vertical accelerations of bridges having 9m, 12m and 18m span length were investigated and compared with the limit values specified in Korean railway bridge specification.
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In Korea mid chord offset method has been used to measure the track irregularities. This method has been also used all over the world widely because of its accessibility and the operational excellence for measured data. But it has been pointed out recently that track irregularities reconstructed from measured data have unexpected noise in the high frequency area as the defect of this way. This study shows the cause of noise which occurs during reconstructing process and mentions the solutions briefly.
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In this paper, a numerical method for vehicle-track interaction analysis is developed to evaluate vertical dynamic force subjected to rail surface. A vehicle is modelled by lumped masses system and track by multi layered continuous beam system. The equation of motion of vehicle and track interaction system is derived by considering compatibility condition at the contact points between wheel and rail. The input vibration source is given by the empirical formula of power spectral density of track irregularity, which is suggested by FRA. Using this method, dynamic impact factors with the train speed are evaluated.
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The elasticity of the contact wire is one of important static parameters for the catenary system. This paper presents how to analyse the elasticity of the catenary system using both simple string model method and finite element method with their formula. Analysis results obtained by these two methods for KTX catenary system are compared. A measurement of the elasticity for the KTX catenary under construction which is located near Kumkang bridge is made for the comparison with the analysis results. Both a dynamic and a static methods are tried for the measurement. Because of wave propagation, the dynamic method with 5 km/h running presented an asymmetric variational pattern of the elasticity while the static method presented a symmetric pattern of the elasticity in the span. Measured elasticity using the static method is found to be a little higher than the analysis results. But, the static method can presented us a variational pattern of the elasticity in the span similar to the analysed results. Therefore, the static method can be used for evaluating the elasticity of the catenary system
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The design of sleeper in high-speed railway turnouts is complicated and time-consuming because the length and loading position of sleepers change continuously along the turnout line. It is, therefore, necessary to develop an automated design program which can design automatically the PSC sleepers in turnout region. In this study, a computer program for automatic design of turnout sleepers was developed based on graphic user-interface(GUI) environment. The structural analysis is performed considering the varying loading position of vehicular wheels. The sleepers are treated as located on elastic supports. The user can choose the desirable shape of sleepers before starting the detail design. The present study allows more realistic and automatic design of PSC sleepers in high-speed railway turnouts.