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REFERENCE LINKING PLATFORM OF KOREA S&T JOURNALS
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Journal of the Korean Society for Railway
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Journal DOI :
Korean Society for Railway
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Volume & Issues
Volume 10, Issue 6 - Dec 2007
Volume 10, Issue 5 - Oct 2007
Volume 10, Issue 4 - Aug 2007
Volume 10, Issue 3 - Jun 2007
Volume 10, Issue 2 - Apr 2007
Volume 10, Issue 1 - Feb 2007
Selecting the target year
A Study on the Optimal Train Recognition Ratio Instrumentation based on RFID
Kang, Min-Soo ; Jung, Eu-Bong ; Lee, Key-Seo ;
Journal of the Korean Society for Railway, volume 10, issue 6, 2007, Pages 633~639
This study proposes an optimal condition to recognize a train using RFID. In order to recognize a moving train, bandwidth, an angle of antenna and the location of a tag should be considered. In this study, a field test was conducted using two different bandwidths (900MHz and 2.45GHz), four angles of antenna(0, 30, 45, and
), different velocities (10, 30 and 50km), and three different locations of tags. The field test verified the optimal condition for recognition of a train, The present study convinced that location detection and tracking of rail freight can be monitored in real time. The present technology can be applied to railway signals including detecting and tracking such as EURO Balis.
A Study on the Development Countermeasure of Railway Industry through Technology Transfer of Train System
Lee, Hi-Sung ; Kang, Tae-Won ;
Journal of the Korean Society for Railway, volume 10, issue 6, 2007, Pages 640~644
This paper suggests that the introduction of Seoul-Pusan High Speed rail system makes related railway industry to be developed through transfer of high technology and other related industries to be jointly grown by technology' ripple effects. Technology transfer and localization implementation process in the period of technology introduction was reviewed synthetically and problems at that period was also analyzed. And technology development countermeasures of railway industry was discussed in order to maintain and expand railway system technology in the future.
Design and Fabrication of a Surge Impedance Meter
Kil, Gyung-Suk ; Rhyu, Keel-Soo ; Kim, Il-Kwon ; Moon, Byung-Doo ; Kim, Hwang-Kuk ; Park, Chan-Yong ;
Journal of the Korean Society for Railway, volume 10, issue 6, 2007, Pages 645~649
Ground systems flow fault currents into the ground, and suppress Ground Potential Rise (GPR) by the current. In this paper, we designed and fabricated a surge impedance meter to analyze the ground impedance in wide frequency ranges. The meter consists of a surge generator, a high speed sample/hold (S/H) circuit and an associated electronics. The surge generator produces surge voltage up to 5kV in ranges of
. Field tests were carried out to evaluate the surge impedance meter at a driven-rod ground system. The results showed that surge impedance of ground systems should be measured by various fast surge waveforms, since the impedance increases as the rise time of applied voltage increases.
Measurement and Analysis of Transient Voltage for an Inverter-fed Induction Motor
Kil, Gyung-Suk ; Rhyu, Keel-Soo ; Park, Dae-Won ; Cho, Young-Jin ; Cheon, Sang-Gyu ; Choi, Su-Yeon ;
Journal of the Korean Society for Railway, volume 10, issue 6, 2007, Pages 650~654
Induction motors are widely used as a source of driving force in electric vehicles and pulse width modulation (PWM) inverters are applied to their operation. The issue is that insulation of inverter-fed induction motors (IFMs) are more stressed than in line-powered motors by transient voltages. This paper dealt with experimental results on transient voltage produced by the PWM operation of an induction motor. The peak and the dv/dt of transient voltage depending on the length of power feeding cable and operating frequency were investigated. In the experiment, transient voltages up to 3.3PU of the rated-inverter voltage were recorded for the cable length of 50m. As the cable length is increased, the peak voltage appeared at the motor terminals increases. This phenomenon can be explained by the reflection and the transmission of travelling wave. Consequently, special care for the cable length between the motor and the inverter should be taken in the use of IFM to ensure the full life of insulation system.
Analysis on Cost-effectiveness of a Train Simulator
Kim, Sa-Kil ; Byun, Seong-Nam ;
Journal of the Korean Society for Railway, volume 10, issue 6, 2007, Pages 655~659
The purpose of this paper is to analyze cost-effectiveness of a train simulator. The cost-effectiveness of training program is assessed by multiplying transfer effectiveness ratio (TER) by training cost ratio (TCR). If their product is less than one, the program is not cost effective. Even if a program is not cost effective, however, safety considerations may be important to consider. Findings indicated that each type of train simulators might be used with each type of training programs appropriately for improving cost-effectiveness of a train simulator.
Torque Measurement of Tripod Shaft for HSR-350x
Kim, Sang-Soo ; Kim, Young-Guk ; Kim, Ki-Hwan ; Park, Choon-Soo ;
Journal of the Korean Society for Railway, volume 10, issue 6, 2007, Pages 660~664
Korea High-speed Railway (HSR-350x) was developed by Korean government, several institutes, and related companies. HSR-350x was investigated its performance and tested at the high speed line. In 2004 December, HSR-350x was run over 350km/h and proved its running performance. And Korean Train Express (KTX) served the commercial traffic for 4 years. These high speed railways have 12 motors to transfer the traction effort or the braking force. To obtain the load of the transfer shaft, it is necessary to measure the transferred torque of the shaft. In this paper, authors propose the construction the measurement system fur monitoring the force transferred to the train from the motor The system was installed to the tripod shaft which is located between the reduction gears and it measures the mechanical load directly.
A Study on the Temperature Change of Braking Disc and Thermal Conductivity during the Service
Kim, Jae-Hoon ; Goo, Byeong-Choon ; Suk, Chang-Sung ;
Journal of the Korean Society for Railway, volume 10, issue 6, 2007, Pages 665~669
This study investigates the temperature change and thermal conductivity for the braking disc of the railway vehicle due to the types of train and service conditions. The temperature change was measured by non-contact Infrared thermometers. Average temperature was measured between
due to types of train and service section. In the same service section, the surface temperatures of Saemaul train were higher than Mugungwha train; the reason might have been the average service speed of Saemaul train (83km/h) was higher than Mugungwha train (107km/h), and the weight was similar 39t (Mugungwha) and 39.3t (Saemaul). But the maximum surface temperature was measured on the Mugungwha train; however the difference was not too big with the maximum temperature of Saemaul train. Also, the disc surface temperatures were changed due to the material of lining; metal and non-asbestos, on the same train and the same service section. In addition. the thermal conductivity was tested the thermal conductivities were increased by the increasing of the temperature. The change is too big between
. But each average value is small. and the mechanical property change is very low. As a result, we conclude that this disc is suitable for usage between
The Change of Shinchon Railway Station in Kyungui Line
Kim, Jong-Hun ;
Journal of the Korean Society for Railway, volume 10, issue 6, 2007, Pages 670~677
This study examines the change of Shinchon railway station in Kyungui Railway from 1920 up to now. Kyungui Railway was constructed in order to prepare the war against Russia by Japan in 1905. Shinchon station was constructed in 1920 for the sake of convenience of people who lived near Seoul. Recently the development of Shinchon staton was demended because of the possibilities of economic development and the location of Shinchon station. But at the same time there are many opinions against the development of Shinchon station because it has many great memories and it is a kind of symbol of modem life in Shinchon. Even though Shinchon station has developed for a shopping center, the location of the old station has been kept. But the shape had changed because of the new railway station. So the purpose of this paper is considering how to solve the conflicts between the development and the preservation of historic places in the cities which is one of the most serious pending issues.
The Development of Discriminant Models for Subway Inner Noise
Kim, Tae-Ho ; Do, Hwa-Yong ; Won, Jai-Mu ; Yoon, Sang-Hoon ;
Journal of the Korean Society for Railway, volume 10, issue 6, 2007, Pages 678~684
This research has defined the factors of noise in cars during subway train services, which is surfacing as a new environmental trouble. It shows additional accomplishment of a discerning analysis on the standard of noise regulation as well as its seriousness. According to the Enforcement Regulations for Noise and Vibration under the Ministry of Environment and its standard noise regulation figure 70dB, we divided two groups of which train noise figures are over and under 70dB respectively, and used their 359 results about noise, geometric structures and operation elements, for this analysis. The results and suggestions are following. First of all, when we discern the seriousness of noise in a train, the track type has mattered in geometric structure and the velocity in operation elements. Therefore, when we construct subway from now on, we should take the track type in consideration and establish plans to keep proper speed in respect of operation. Secondly, the established discernment model in this research can be used in making alternative plans or improvement of subway trains hereafter, showing relatively high accuracy of estimation. Consequently, the readjustment of geometric structure and operation elements is needed, not to make it over the regulation standard of noise in case the noise in train is serious. The discriminant model of this research can be used as elementary material for comfortable and safe subway trains, making the estimation of noise seriousness possible.
Study on Coordinate Transformation of Railroad Central Linear-line Using the Railroad Reference Points
Moon, Cheung-Kyun ; Heo, Joon ; Kang, Sang-Gu ; Kim, Il-Joo ; Park, Jae-Hong ; Kim, Sung-Hoon ;
Journal of the Korean Society for Railway, volume 10, issue 6, 2007, Pages 685~691
In this paper through Honan high-speed railroad which is planned with the north and south axis, we will verify the feasibility of the coordinate conversion using railroad control points after regarding current planned-railroad as the linear central axises. From analysis, distortion of Y axis varies 21 cm to 40 cm diminishing to a gentle straight line, distortion of X axis varies 14 cm to 29 cm. Through a revision, the deviation value between the coordinates were 6 mm to 9 mm and it satisfied the allowable error of national geographic information institute which is following ITRF (International Terrestrial Reference Frame) and cadastral boundary survey (10 cm). consequently the coordinate conversion is possible using railroad control points as common control points.
Characteristics of Curved Track Behaviors according to Traveling Tilting Train
Park, Yong-Gul ; Choi, Jung-Youl ; Sung, Deok-Yong ; Chun, Dae-Sung ;
Journal of the Korean Society for Railway, volume 10, issue 6, 2007, Pages 692~700
A trial run of locally-developed tilting train has been in process on Chungbuk line since the test vehicle was first produced. For the system stabilization, interface verification among the systems including track, structure, catenary and signaling system, not to mention the rolling stock, is very crucial. In the area of wayside structure, the stability of track structure and train run shall be evaluated through the review of impact by increased speed by developed train on track structure. The study thus was intended to evaluate the impact on track while a tilting train is running the curve section, which is vulnerable to accelerated train speed. The analysis of tilting train test running the part of Chungbuk line and Honam line was conducted to identify the impact on existing track performance by tilting train. To identify the movement behavior of each part of track while tilting train, high speed train and traditional train (Mugunghwa and freight train) were running the existing line, wheel load, lateral wheel load, rail bending stress, vertical and lateral displacement of rail and vertical displacement of sleeper were compared and analyzed so as to evaluate the expected impact by tilting train for improving the train speed.
Stability Evaluation of Track on Conventional Line According to Traveling Tilting Train
Park, Yong-Gul ; Eum, Ki-Young ; Choi, Jung-Youl ; Sung, Deok-Yong ;
Journal of the Korean Society for Railway, volume 10, issue 6, 2007, Pages 701~708
A tilting train, which was developed to run the curve section without reducing the speed and compromising the riding quality, can improve the speed so as to reduce the travel time, compared to the existing trains. Then the force generated by the train operation to the track is in proportion to train operation speed, which means the track shall bear the increased force as much as the increase in train operation speed. Particularly, wheel load and lateral wheel load generated by train operation and distributed to the rail tend to cause the track to suffer the strain and furthermore the severe disaster such as derailment. To deal with such problem and ensure the train will run safety and stably, the tolerance in wheel load change, lateral wheel load and derailment coefficient was determined for quantitative evaluation of the train operation stability. In this study, derailment coefficient of inner and outer rail at existing curve section of tilting train was determined to evaluate the curve radius, possibility of acceleration and the need of rail improvement, which was then compared with the existing traditional train and high speed train. Conducting the quantitative evaluation of dynamic wheel load and lateral wheel load of each train, which was based on field survey, derailment coefficient and static & dynamic wheel load change, which serve the evaluation criteria of train operation stability, were determined for comparison with the standards, thereby analyzing the stability of the tilting train.
Concept Design of an Active Steering Bogie for Urban Railway Vehicles
Park, Joon-Hyuk ; Hur, Hyun-Moo ; Koh, Hyo-In ; You, Won-Hee ;
Journal of the Korean Society for Railway, volume 10, issue 6, 2007, Pages 709~716
An active steering bogie has been theoretically proved to improve both stability and steering performance remarkably. However, It has not been commercialized yet even though many researchers have been trying to develop it because some technical difficulties still exist such as information acquisition fer active control, increasing mechanical components, high energy consumption, fail-safe problem and so on. To solve those problems, an advanced active steering mechanism is proposed in this paper. With this mechanism, required control force is small enough to use direct drives. Therefore, the number of additional mechanical components can be minimized since mechanical transducers like gears are not necessary. Fail-safe function can be also inserted easily. In this paper, concept design of the proposed active steering bogie is introduced and the possibility is verified through computer simulation using linear dynamic model.
Measurement and Analysis of Regenerative Energy in DC 1500V Electric Traction Substation
Bae, Chang-Han ; Jang, Dong-Uk ; Kim, Ju-Rak ; Han, Moon-Seub ; Kim, Yong-Ki ;
Journal of the Korean Society for Railway, volume 10, issue 6, 2007, Pages 717~722
Most of DC 1500V electric railway substations have adopted diode rectifiers to supply stable DC power. However, the diode rectifiers operate in the first quadrant of the voltage-current plane and thus need regenerative inverters which transfer the surplus regenerative power caused by regenerative braking of electric train sets into the grid. In order to select the proper capacity and installation position of regenerative inverter, it needs to investigate the consumed and regenerative energy of the electric traction substations in advance. This paper presents an analysis of regenerative energy in two substations operating in Seoul Seolleung and Kwangju Yangdong substations. DC line voltage and feeder currents are measured for a day to calculate consumed and regenerative power far four feeders. We calculated an amount of regenerative energy consumed in other feeders and estimated the cost reduction in energy consumption due to the reuse of regenerative energy
A Study on
and PM10 Changes by Operation of KTX HVAC-Pressurization Equipment in Tunnel Sections
So, Jin-Sub ; Yoo, Seong-Yeon ;
Journal of the Korean Society for Railway, volume 10, issue 6, 2007, Pages 723~729
The Ministry of Environment established a guide line in December 2006, "Indoor Air Quality Management guidelines in Public Facilities." As the items of the guideline,
(Carbon dioxide) and PM10 (particulate matter) is shown to Level 1 and 2. Therefore trains and subways are included. There are a lot of tunnels by the lay of mountains on KTX (Korean Train Express) service. HVAC (Heating Ventilating and Air-conditioning)-pressurization equipment on KTX is various functioning flaps blocking outside pressure waves. At that time, the fresh air is blocked by flap operation and the air is circulated by return air. In this study, we measured the time series of
and PM10 concentrations in the KTX passenger cabin during the train service of Gyongbu line (Seoul-Busan) and Honan line (Yongsan-Mokpo) from July 2006. Also, analyzed the air quality by operation of KTX HVAC-pressurization equipment in tunnel passing point. As a result, PM10 concentration was totally lower than the regulation values. However,
was highly correlated with several tunnels, such as Oksan-Otan, Godeung-Hyudae and Gaechak-Iijik tunnel. but, the indoor air quality of KTX train have been proved satisfy the recommendation the Ministry of Environment guidelines.
Design and Assessment of a Watch Dog Timer for Safety Improvement of an Embedded Railway Signal Controller
Shin, Duc-Ko ; Lee, Kang-Mi ; Lee, Jae-Ho ; Kim, Yong-Kyu ;
Journal of the Korean Society for Railway, volume 10, issue 6, 2007, Pages 730~734
In this paper, we suggest the criticality of Hidden Failure with regard to the design of watch dog timer, used to detect HALT on railway signaling embedded controller, via FMEA and FTA. Hidden Failure means reliability and safety degradation of the system due to any failure occurred on elements added for fault tolerance. In this paper, therefore, we design vital watch dog timer to prevent the system from operating in low SIL conditions and assess the safety of circuit on failure occurrence to demonstrate that safety degradation problems owing to existing design are supplemented.
Estimation of Noise around the Turnout System Induced by the Tilting Train
Eum, Ki-Young ; Lee, Jin-Wook ; Lee, Chin-Hyung ;
Journal of the Korean Society for Railway, volume 10, issue 6, 2007, Pages 735~741
A turnout system which permits trains to pass from one track to another is a combination of the switch, the crossing, lead rails which are necessary to connect the switch and the crossing, two guard rails and a switch machine for operating the switch. In Korea, it has been planned to adopt the high speed tilting train which is suitable for the circumstance of Korea and operates at the maximum speed of 180 km/h, at conventional lines by the year of 2010. For the present, the prototype of the tilting train has been fabricated, and has undergoing a trial run. In this study, evaluation of noise around the turnout system induced by the tilting train has been implemented through the field measurements.
A Study on an Efficient Double-fleet Operation of the Korean High Speed Rail
Oh, Seog-Moon ; Sohn, Moo-Sung ; Choi, In-Chan ;
Journal of the Korean Society for Railway, volume 10, issue 6, 2007, Pages 742~750
This paper presents a mathematical model for a double-fleet operation in Korean high speed rail (HSR). KORAIL has a plan to launch new HSR units in 2010, which are composed of 10 railcars. The double-fleet operation assigns a single-unit or two-unit fleet to a segment, accommodating demand fluctuation. The proposed model assumes stochastic demand and uses chance-constrained constraints to assure a preset service level. It can be used in the tactical planning stage of the rail management as it includes several real-world conditions, such as the capacities of the infra-structures and operational procedures. In the solution approach, the expected revenue in the objective function is linearized by using expected marginal revenue, and the chance-constrained constraints are linearized by assuming that demands are normally distributed. Subsequently, the model can be solved by a mixed-integer linear programming solver fur small size problems. The test results of the model applied to Friday morning train schedules for one month sample data from KTX operation in 2004 shows that the proposed model could be utilized to determine the effectiveness of double-fleet operation, which could significantly increase the expected profit and seat utilization rates when properly maneuvered.
A Study on the Enterprise Architecture to Develop the Requirements for Railway Safety Support information Systems
Lee, Byoung-Gil ; Lee, Jae-Chon ;
Journal of the Korean Society for Railway, volume 10, issue 6, 2007, Pages 751~757
This paper is concerned with the development of the requirements for railway safety support information systems. The five safety elements at the system level have been modeled based on the enterprise architecture approach. Specifically, the modeling has been carried out as follows. First, the requirements are derived according to EIA-632 process. Also, the possible scenarios on the accident-investigation-support are developed from the help of relevant personnel in the area. The developed scenarios are reflected in modeling the operational and system architectures of DoDAF approach using a CASE tool. From this architecture model, we can easily get the specifications required for the operations. These results can give the improved understanding of the railway safety system to the members of diverse teams and areas working for the system development.
An Efficient Network Mobility Handoff Scheme Based on Movement Pattern of a Train
Lee, Il-Ho ; Lee, Jun-Ho ;
Journal of the Korean Society for Railway, volume 10, issue 6, 2007, Pages 758~765
In this paper, we propose an efficient seamless handoff scheme to minimize packet loss and unnecessary packets on the Internet using the peculiar mobility characteristics of public vehicles such as trains. MR (Mobile Router) in a train visits each AR (Access Router) in the fixed order. As the MR detects reachability to the NAR (Next Access Router) on the new link, the PAR (Previous Access Router) can directly deliver packets from MR's HA (Home Agent) to the NAR according to the HML (Handoff Mobile router List). Then. the NAR buffers them until the MR finishes L3 (Layer 3) handoff procedure with the NAR. Therefore, our scheme can support a seamless handoff without the packet loss and unnecessary packets on the Internet. The result of our performance evaluation has shown that the proposed scheme could provide excellent performance, compared with the NEMO basic support protocol and the Bi-casting protocol.
Development of the Operation Cost Models for Preliminary Assessment of the Urban Railways
Lee, Jae-Myung ; Won, Jai-Mu ; Rho, Jeong-Hyun ;
Journal of the Korean Society for Railway, volume 10, issue 6, 2007, Pages 766~771
In this research, we were going to make the function which can forecast the operating cost of metropolitan railroad that is performing a role of assistant highway within the city. In order to do this, based on service records of subway line 1st to 8th in Seoul, we extracted 23 variables which can affect to the operating cost, and we selected the final variable for estimate the function of operating cost from correlation among variables and influence analysis. Then, we performed regression analysis by stages using final variable. 6 independent variables are chosen for presuming the operating cost, and we obtained the final 3 variables (quantity of holding motor cars, peak quantity of possessed motor cars, and quantity of stations) as a result of regression analysis. Through this research, function of operating cost of metropolitan railroad has better applicability than existing preliminary validity, and it is used by further preliminary validity investigation and master plan or validity investigation which is accompanied by operation designing, thus we expect that it could make a great contribution to the priority order of investment for metropolitan railroad or process of policy decision.
A Study on the Wear Characteristics of R/S Passing through Curves
Lee, Hi-Sung ;
Journal of the Korean Society for Railway, volume 10, issue 6, 2007, Pages 772~778
For the wear characteristics assessment of Saemaul train passing through curves, an analysis model for multi-car system has been developed. By using this model and ADAMS/Rail, sensitivity analyses have been conducted for the wear characteristics by changing the related parameters. At low speed, the wear number and the sliding mean of right wheel showed higher than left wheel, while those of left wheel showed higher than right wheel at high speed. According to the decrease of curve radius, the wear number and the sliding mean were increased. When the length of transition curve was increased, the wear number and the sliding mean was increased. And according to increase of cant, the wear number and the sliding mean were increased.
Factor Analysis for Improvement of Convenience and Safety in the Interior Design of Subway Trains
Jin, Mi-Ja ; Han, Suk-Woo ;
Journal of the Korean Society for Railway, volume 10, issue 6, 2007, Pages 779~785
This study identifies visible/invisible factors and analyzes facilities, structure, and visible perceptive contents in the aspects of operation and efficiency with a focus on the interfaces between interior design of the subway and users. More specifically, it diagnoses the requirements and empirically presents improvements. As the interior design in the subway trains is fur the public reflecting the value, consciousness, and behaviors of users, it should be approached through the application of the concept of universal design that considers the potential needs and psychological satisfaction of users. In arranging the indoor of the vehicles, the conditions for the facilities should be specified through the interdisciplinary approach from professional fields including ergonomics and psychology, the path of flow should be induced through the use of space and the analysis of passengers' behaviors, an integrated planning should be re-established, and continuous evaluations of basic guidelines, manuals, and requirements should be made.
Experimental Investigation of Noise Generation from the Inter-coach Spacing of a High-speed Train
Choi, Sung-Hoon ; Park, Choon-Soo ; Park, Jun-Hong ; Kim, Sang-Soo ;
Journal of the Korean Society for Railway, volume 10, issue 6, 2007, Pages 786~791
Aerodynamically generated noise is dominant when the train speed approaches 300km/h. This noise sources is caused by the turbulent flow separations or vortex shedding from the train structure. Experiments were performed to investigate the characteristics of aerodynamic noise sources generated from exterior of the KTX trains and HSR-350x, especially from the inter-coach spacing. Measurements of both the inside and outside of the cabin are carried out to investigate the characteristics of the noise. Effect of the size of the mud-flap has been investigated through an wind tunnel test and it has been found that the low frequency noise is strongly dependent on the size of the gap. Also performed is an array measurement to locate different noise sources from the high-speed train. spectral characteristics of exterior noise sources are examined.
A Study on the Effects of Leadership Perception on the Organizational Effectiveness in Railway Organizations : Verification of Multiple Leadership Effects
Choo, Jun-Seoup ; Shin, Tack-Hyun ;
Journal of the Korean Society for Railway, volume 10, issue 6, 2007, Pages 792~799
The purpose of this article is to depict the relationship between the frames of leadership and the dependent variables such as job satisfaction, respect from subordinates, and promotion speed of boss. To attain this purpose, for types of multiple leadership frames, such as structural, human resources, political, and symbolic frames were surveyed through questionnaire and analyzed by SPSS.
A Study on the Critical Speed of 1/5 Scaled Bogie Model
Hur, Hyun-Moo ; Park, Joon-Hyuk ; Kim, Min-Soo ; You, Won-Hee ; Park, Tae-Won ;
Journal of the Korean Society for Railway, volume 10, issue 6, 2007, Pages 800~805
The critical speed of railway bogie is very important in terms of the verification of the vehicle design procedure and safety. The dynamic performance of bogie is tested on the railway roller rig in a laboratory in place of field testing on track. But, the testing on the full scale roller rig caused many problems relating to test costs, test time and has the difficulty in test condition setup. To overcome these problems, scaled models were used in the filed of railway vehicle design and test. In this paper, we have studied the critical speed of scaled bogie model. We have made the 1/5 scaled bogie, the scaled roller rig and analyzed the critical speed of the scaled bogie through the numerical simulation and running test of the scaled bogie. We have confirmed that the analysis results of the critical speed correspond with the test results.
A Study on the Measurement of New Concept for the Contact Force between Rail and Wheel
Hong, Yong-Ki ; You, Won-Hee ; Lee, Hi-Sung ;
Journal of the Korean Society for Railway, volume 10, issue 6, 2007, Pages 806~811
The derailment is defined as phenomena in which the wheels run off the rail due to inordinate lateral force generated when wheel flange contacts with the rail. Derailment coefficient is typical standard assessing running safety and derailment. The traditional method measuring by strain gage adhered to wheels is very complicated and easy to fail. It also requires too much cost and higher measurement technique. Therefore it can hardly ensure safety because we can't confirm at which time we need to identify safety. In this paper, we principally researched the method measuring easily wheel load generated by contacts between wheel flange and the rail, and lateral force. Correlation of vibration and displacement which was related physical amounts of wheel load and lateral force, was investigated and analyzed through analysis, experiment and measurement. And it is presents new measurement method of derailment coefficient which can estimate derailment possibility only by movement of vibration and displacement, by which we understand the rate for acceleration and displacement to contribute wheel load and lateral force and compare actual data of wheel load and lateral force measured from wheel.