• Title, Summary, Keyword: 콘크리트궤도

Search Result 227, Processing Time 0.048 seconds

Design Graphs for Asphalt Concrete Track with Wide Sleepers Using Performance Parameters (성능요소를 반영한 광폭 침목형 아스팔트콘크리트 궤도 설계그래프)

  • Lee, SeongHyeok;Lim, Yujin;Song, Geunwoo;Cho, Hojin
    • Journal of the Korean Society for Railway
    • /
    • v.19 no.3
    • /
    • pp.331-340
    • /
    • 2016
  • Wheel load, design velocity, traffic amount (MGT), stiffness and thickness of sub-layers of asphalt concrete track are selected as performance design parameters in this study. A pseudo-static wheel load computed considering the dynamic amplification factor (DAF) based on the design velocity of the KTX was applied to the top of asphalt concrete track for full three dimensional structural analysis using the ABAQUS program. Tensile strains at the bottom of the asphalt concrete layer and vertical strains at the top of the subgrade were computed from the structural FEA with different combinations of performance parameter values for one asphalt concrete track section. Utilizing the computed structural analysis results such as the tensile strains and the vertical strains, it was possible to develop design graphs to investigate proper track sections for different combination of the performance parameters including wheel load, design velocity, traffic amount(MGT), stiffness and thickness of asphalt concrete layers for any given design life. By analyzing the proposed design graphs for asphalt concrete track, it was possible to propose simple design tables that can be used by engineers for the effective and fast design of track.

A Behavior Analysis of HSR Concrete Slab Track under Variety of Rail Pad Static Stiffness on Fatigue Effect (피로효과를 고려한 레일패드의 정적스프링계수 변화에 따른 콘크리트 슬래브 제도의 거동분석)

  • Park, Yong-Gul;Kang, Kee-Dong;Choi, Jung-Youl
    • Journal of the Korean Society for Railway
    • /
    • v.10 no.5
    • /
    • pp.499-505
    • /
    • 2007
  • The major effective of this study is to investigate the fatigue effects of rail pad on High Speed Railway with concrete slab track system. It analyzed the mechanical behaviors of HSR concrete slab track with applying rail pad stiffness based on fatigue effect (hardening and increasing stiffness) on the 3-dimensional FE analysis and laboratory test for static & dynamic characteristics. As a result, the hardening of rail pad due to fatigue loading condition are negative effect for the static & dynamic response of concrete stab track which is before act on fatigue effect. The analytical and experimental study are carried out to investigate rail pad on fatigue effected increase vertical acceleration and stress and decrease suitable deflection on slab track. And rail pad based on fatigue effect induced dynamic maximum stresses, the increase of damage of slab track is predicted by adopting fatigue effected rail pad. after due consideration. The servicing HSR concrete slab track with resilient track system has need of the reasonable determination after due consideration fatigue effect of rail pad stiffness which could be reducing the effect of static and dynamic behavior that degradation phenomenon of structure by an unusual response characteristic and a drop durability.

Determination on the Reinforced Roadbed Thickness of Concrete Track at Embankment Section (흙쌓기 구간에서 콘크리트궤도 강화노반의 두께 결정에 관한 연구)

  • Lee, Il-Wha;Lee, Sung-Jin;Sin, Min-Ho;Hwang, Sun-Kun;Lee, Chang-Jin
    • Journal of the Korean Society for Railway
    • /
    • v.12 no.6
    • /
    • pp.835-843
    • /
    • 2009
  • Recently the more stable roadbed is required due to the high speed and design load. Therefore the reinforced roadbed was introduced as the solution. But the thickness and stiffness of reinforced roadbed in design code is being conservatively assessed by the foreign code without considering the domestic construction condition. In this paper, adequate Young's modulus, drain capacity, freezing depth, economical efficiency, bearing capacity, construction condition and 3-D finite element method were employed to determine the proper thickness of reinforced roadbed at the embankment section.

The Effect of Pile Distallation on the Reduction of Cumulative Plastic Settlement (말뚝 설치를 통한 콘크리트궤도의 누적소성침하 감소 효과)

  • Lee, Su-Hyung;Lee, Il-Wha;Lee, Sung-Jin;Kim, Dae-Sang
    • Journal of the Korean Geotechnical Society
    • /
    • v.24 no.5
    • /
    • pp.129-137
    • /
    • 2008
  • An active application of concrete track is being expected far the future constructions of Korean railroad. In comparison with the existing ballasted tract, a concrete track is very susceptible for the settlement, since its rehabilitation requires much time and cost. When a concrete track is constructed on fine-grained subgrade soil, excessive cumulative plastic settlements due to repetitive train road may occur. In this case, the settlement of the concrete track may be effectively reduced by installing a small number of small-diameter piles beneath the track. This paper presents the effect of pile installation on the reduction of cumulative plastic settlement of concrete track. A method combining experiential equation and numerical method is proposed. Using an existing experiential equation and the estimated earth pressure distribution, the cumulative plastic strain was calculated. From the results, it is verified that the effects of the pile installation is significant to effectively reduce the cumulative plastic settlement of concrete track. The reduction effects of the cumulative plastic settlement according to the pile number and pile arrangement are presented.

Development of Design Chart for Investigating an Additional Rail Stress and Displacement on CWR(II) - Design Chart for Railway Bridge of Conventional Line (장대레일 부가축력 및 변위 검토를 위한 설계차트 개발(II) - 일반철도 교량 설계차트)

  • Choi, Il-Yoon;Lim, Yun-Sik;Yang, Sin-Chu;Choi, Jin-Yu
    • Journal of the Korean Society for Railway
    • /
    • v.12 no.4
    • /
    • pp.574-581
    • /
    • 2009
  • Displacement of the bridge and additional rail stress due to interaction between track and bridge should be limited to the design criteria. Interaction analysis was conducted to investigate the displacement and additional rail stress on CWR in railway bridge of conventional line. Particularly, various parameters affecting interaction phenomena were taken into account in the analysis to enhance an applicability. These parameters included configuration of structure, stiffness of deck and support, steel/concrete bridge, ballast/concrete track and FM/MFM type etc. The results were presented in the form of the design chart which could be useful in preliminary design of the bridge.

Experimental Study of Characteristics of Longitudinal Resistance Behavior of Fasteners in Concrete Track on Bridges (교량 상 콘크리트궤도 체결장치의 종저항 거동특성에 대한 실험적 연구)

  • Yun, Kyung-Min;Park, Beom-Ho;Min, Kyung-Hwan;Lim, Nam-Hyoung
    • Journal of the Korean Society for Railway
    • /
    • v.19 no.5
    • /
    • pp.638-646
    • /
    • 2016
  • CWR (continuous welded rail) tracks on high-speed railway bridges have much more complicated axial force distributions caused by track-bridge interaction than those behaviors on embankments, and additional problems caused by track-structure interaction with the axial force of the CWR. In order to analyze and limit other physical phenomena caused by track-bridge interaction, a design guideline (KR C-08080, longitudinal track-bridge interaction analysis) is used when designing CWR track on bridges. Domestic analysis and design methods for track-bridge interaction follow the UIC 774-3R, and they suggest conservative methods and deterministic properties. Recently, many studies analyzing the methods of track-bridge interaction considering the loading history are being carried out; however, there has been insufficient studies of the variation of the resistance properties with a consideration of the actual loading history. In this study, the performances of rail fastening systems used for concrete track on bridges were tested and analyzed while considering the loading history. For this purpose, longitudinal and vertical loading combinations, applied in order to simulate the practical conditions and resistance characteristics (stiffness and elastic limit displacement), are analyzed through the experimental results. Also, a comparison study was conducted with the properties in the KR Code.

Damage Status of Turnout System with Wooden Sleeper of Concrete Track on Urban Transit (도시철도 콘크리트궤도 목침목 분기기의 손상현황)

  • Choi, Jung-Youl;Han, Kyung-Sung;Bong, Jae-Gun;Jang, Cheol-Ju;Chung, Jee-Seung
    • The Journal of the Convergence on Culture Technology
    • /
    • v.5 no.4
    • /
    • pp.379-385
    • /
    • 2019
  • The purpose of this study is to investigate the damage status of wood sleepers on concrete track of urban transit at different locations and to analyze the causes of damages. In addition, the turnout maintenance history during the service period of about 24 years was analyzed in conjunction with the train passing tonnage and that was to compare the current repair history. The most frequent damage components were rail, tie plate, spike and wooden sleeper. And, the damage caused by the defect of the rail fastening system such as spike and tie plate according to the deformation of the wooden sleeper was analyzed as the main type of damage. As a result, the damage of track components of turnout system was on the increase because they are directly affected by the train passing tonnage. The supplementary points of the check sheet for current turnout maintenance were derived and the improvement proposal was suggested based on the research results.

Influence of Rail Supporting Spacing of Railway Bridge Deck Ends on Bridge-Track Interaction Forces (교량-궤도 작용력에 대한 교량 단부에서의 레일지지점간격의 영향)

  • Choi, Jun-Hyeok
    • Journal of the Korean Society for Railway
    • /
    • v.17 no.4
    • /
    • pp.245-250
    • /
    • 2014
  • This paper, as a study for the serviceability design of railway bridges with concrete track, presents the effects of design parameters of tracks and bridges on the forces acting on the rail supports of the track. To calculate the forces acting on the track, an unequal spacing discrete supported model with different spacing of rail supports was induced. Design parameters are the rail support spacing of expansion joints above abutments or piers of bridges, the distance from the support of a girder to the last rail support on the end of the girder, and the number of additional rail supports. The causes of the displacement of track are axial force, unit vertical displacement, and unit rotation. From the analysis, the maximum compressive force and the maximum uplifting force acting on the rail supports were determined and the effects of the rail support spacing on the forces acting on the track were presented.

Experimental Study on Characteristics of Deformation for Concrete Track on Railway Bridge Deck End induced by Bridge End Rotation (철도교량 단부 회전에 따른 콘크리트 궤도의 변형특성에 관한 실험적 연구)

  • Lim, Jongil;Song, Sunok;Choi, Jungyoul;Park, Yonggul
    • Journal of the Korean Society for Railway
    • /
    • v.16 no.3
    • /
    • pp.217-225
    • /
    • 2013
  • In this study, by considering the rail fastening support distance and the distance between the bridge and the abutment, the behavior of concrete track installed on a railway bridge end deck and the bridge end rotation were analyzed. In order to analyze the track-bridge interaction, bridge and abutment specimens with concrete track structures were designed and used in laboratory testing. At a constant fastening support distance, an increase in the bridge end rotation caused an increase in the displacement of the rail. Therefore, the displacement of the rail directly affects the rail and clip stress. Further, it is inferred that the results of multiple regression analysis obtained using measured data such as angle of bridge end rotation and fastening support distance can be used to predict the track-bridge interaction forces acting on concrete track installed on railway bridge deck ends.

Evaluation on Structural Stiffness and Grouting Efficiency of Concrete Track using Elastic Wave Tests (탄성파 기법을 이용한 콘크리트궤도의 구조강성 및 충전상태 평가에 관한 연구)

  • Lee, Il-Wha;Joh, Sung-Ho;Jang, Seung-Yup
    • Journal of the Korean Society for Railway
    • /
    • v.12 no.1
    • /
    • pp.55-64
    • /
    • 2009
  • Recently, concrete track is replacing ballast track for efficient and economic maintenance of track. It considerably offer less maintenance, a longer service life and reduced life-cycle costs. With the aim of achieving high-quality track construction work, of developing tools for quality assurance in new construction and for later technical inspection of material condition, a quality strategy has to be developed. For these purpose, NDT which is using the seismic wave has carried out in situ studies in the test construction section. The used NDT are SASW test, impact echo test and continuous impact echo test. The test is performed 5,353 times on 49 pre-cast concrete track panels to verify the stiffness structure and grouting efficiency of the track structure. To conclude, because of the non-homogeneous characteristic of concrete material. it is restricted to apply the elastic wave test at some aspect. However it is possible to acquisite a sufficient reliability about structural stiffness and grouting efficiency of concrete track.