• Title/Summary/Keyword: 레일안정성

Search Result 3, Processing Time 0.082 seconds

Field Test to Investigate the Thermal Stress of Continuous Welded Rail on High Speed Railway Bridges in Summer Period (고속철도 교량상 장대레일의 하절기 온도응력 계측)

  • Kwark, Jong-Won;Choi, Eun-Suk;Chin, Won-Jong;Lee, Jung-Woo;Kim, Byung-Suk;Kang, Jae-Yoon
    • Journal of the Korean Society for Railway
    • /
    • v.9 no.2
    • /
    • pp.131-136
    • /
    • 2006
  • Most modern railways, especially the high speed railway tracks, use continuous welded rail(CWR) for the less maintenance. For the CWR track has very few expansion joints, track buckling has always been an unpredictable event and it happens mainly by high compressive stress in rail in summer period. Therefore, it is important to understand the variation of rail stress induced by thermal loads which has direct influence on the rail buckling and stability of railway track. This paper describes the experimental investigation of the variation of rail temperature and stress in a high speed railway track on bridge structure. Field measurement was performed to examine the correlation between the rail temperature and rail stress on the Korean High Speed Railway line. Regression functions were derived from measured data to determine the rail stress f3r an arbitrary rail temperature varies from 20 to 50 degree Celsius.

Stability Analysis for CWR on the Railway Bridges by Linearized Method (선형해석법을 이용한 교량상 장대레일의 안정성 해석 방법 연구)

  • Choi, Young-Gil;Oh, Ju-Won
    • Journal of the Korean Society for Railway
    • /
    • v.12 no.4
    • /
    • pp.472-480
    • /
    • 2009
  • The stability analysis for CWR is difficult in the theory itself because both geometric and material nonlinearity should be considered. Also the analysis results are varied according to the loading history. In contrast to the complexity in the theory, the analysis results for CWR on the railway bridges are quite simple and can be predicted because of a small buckling effect and its negligible nonlinearity. In this study, refined nonlinear analysis methods for the stability analysis of CWR on the railway bridges were developed which consider only material nonlinearity beeause the effects of geometric nonlinearity are nominal. In this study, the analysis results can be found within limited number of iterations with idealized linear force-displacement relationship. From the analysis result comparisons, it was found that the stability analysis for CWR on the railway bridges can be performed effectively by this method.

Behavior Analysis of Fill Slope by Vehicle Collision on Guardrail (가드레일에 차량 충돌 시 성토사면의 거동분석)

  • Park, Hyunseob;Ahn, Kwangkuk
    • Journal of the Korean GEO-environmental Society
    • /
    • v.15 no.2
    • /
    • pp.67-74
    • /
    • 2014
  • Recently, the number of road construction is increasing by industrial development. According to this industrial tendency, the number of traffic accidents are consistently increasing due to increasing number of vehicle on the road. This is mainly because traffic accidents are occurred by various parameter such as negligence of driver, vehicle defects, state of unstable road, natural environment etc. Lane department of vehicles from guardrail is occurring frequently. This type of accident is caused by vehicle performance improvement and shape of vehicle, weak guardrail installation and maintenance. Guardrail has the purpose on prevention such as prevention of traffic accident and prevention of deviating out of road, minimizing damage of driver and vehicle by collision as well as entry into the road through guardrail. Stability evaluation test of guardrail verifies the behavior of guardrail through the crash of truck. At this time, the crash condition has 100 km/h of velocity and $15^{\circ}$ of impact angle. In the case of ground condition, filling slope condition has relatively high bearing capacity of infinite ground towards the test. Guardrail is generally installed on road of shoulder in fill slope in korea. It is possible for stability problem to deteriorate ground bearing capacity in Guardrail in fill slope. The existed study towards stability of guardrail has been carried out in the infinite ground. However, the study on the behavior of fill slope with guardrail is not performed by vehicle collision. Therefore, In this study, the numerical analysis using LS-DYNA was executed for verification on behavior of fill slope with guardrail through vehicle collision. This numerical analysis was carried out with change of embedded depth on installed guardrail post in shoulder of fill slope by vehicle collision and 8 tonf truck crash providing at NCAN (National Crash Analysis Center). As the result, displacement and stress on fill slope are decreased in accordance with the increase of embedded depth of guardrail post. Ground bearing capacity is deteriorated at depth of 450 mm form shoulder of road on fill slope.