• Title, Summary, Keyword: stability of railway slope

Search Result 40, Processing Time 0.035 seconds

The Development of Rail-Transport Operation Control using the Variation of Slope Stability under Rainfall (강우시 사면안전율 변화를 이용한 열차운전규제기준 개발)

  • Kim, Hyun-Ki;Lee, Jin-Wook;Shin, Min-Ho
    • Proceedings of the KSR Conference
    • /
    • /
    • pp.397-402
    • /
    • 2003
  • Infiltration of rainfall causes railway embankment to be unstable and may result in failure. Basic relationship between the rainfall and stability of railway embankment are defined to analyze the stability of embankment by rainfall. An experimental study for defining of infiltration rate of rainfall into slope is conducted in the lab. The results of Rainfall infiltration show that rainfall infiltration is not equal to infiltration as like reservoir because rate of rainfall infiltration is controlled by slope angle. Based on these results, boundary condition of rainfall is altered and various numerical analysis are performed. The variation of shear strength, the degree of saturation and pore-water pressure for railway slope during rainfall can be predicted and the safety factor of railway slope can be expressed as the function of rainfall amount, namely rainfall index. Therefore, it is judged that this rainfall index can be a good tool for the rail-transport operation control.

  • PDF

Risk identification, assessment and monitoring design of high cutting loess slope in heavy haul railway

  • Zhang, Qian;Gao, Yang;Zhang, Hai-xia;Xu, Fei;Li, Feng
    • Structural Monitoring and Maintenance
    • /
    • v.5 no.1
    • /
    • pp.67-78
    • /
    • 2018
  • The stability of cutting slope influences the safety of railway operation, and how to identify the stability of the slope quickly and determine the rational monitoring plan is a pressing problem at present. In this study, the attribute recognition model of risk assessment for high cutting slope stability in the heavy haul railway is established based on attribute mathematics theory, followed by the consequent monitoring scheme design. Firstly, based on comprehensive analysis on the risk factors of heavy haul railway loess slope, collapsibility, tectonic feature, slope shape, rainfall, vegetation conditions, train speed are selected as the indexes of the risk assessment, and the grading criteria of each index is established. Meanwhile, the weights of the assessment indexes are determined by AHP judgment matrix. Secondly, The attribute measurement functions are given to compute attribute measurement of single index and synthetic attribute, and the attribute recognition model was used to assess the risk of a typical heavy haul railway loess slope, Finally, according to the risk assessment results, the monitoring content and method of this loess slope were determined to avoid geological disasters and ensure the security of the railway infrastructure. This attribute identification- risk assessment- monitoring design mode could provide an effective way for the risk assessment and control of heavy haul railway in the loess plateau.

A Study on the Stability Evaluation of Railway Cut-Slope Under Rainfall (강우시 철도 절개사면의 안정성 평가에 관한 연구)

  • 김현기;박영곤;신민호
    • Proceedings of the Korean Geotechical Society Conference
    • /
    • /
    • pp.273-280
    • /
    • 2001
  • In order to evaluate the stability of railway cut-slope under rainfall, explanatory variables and subordinate variables were selected for multivariate analysis. Furthermore the site which had occurred failure due to rainfall was investigated, and by executing multivariate analysis for 121 cases, critical rainfall was defined by the case that had high value of correlation factor. The 0.3 square value of maximum hourly rainfall during 24 hours before failure caused the collapse of railway cut-slope and could be used to estimate the stability of railway cut-slope. From the result of application to a collapse example, the evaluaton method by critical rainfall curve is satisfactory.

  • PDF

Numerical analysis on stability of express railway tunnel portal

  • Zhou, Xiaojun;Hu, Hongyun;Jiang, Bo;Zhou, Yuefeng;Zhu, Yong
    • Structural Engineering and Mechanics
    • /
    • v.57 no.1
    • /
    • pp.1-20
    • /
    • 2016
  • On the basis of the geological conditions of high and steep mountainous slope on which an exit portal of an express railway tunnel with a bridge-tunnel combination is to be built, the composite structure of the exit portal with a bridge abutment of the bridge-tunnel combination is presented and the stability of the slope on which the express railway portal is to be built is analyzed using three dimensional (3D) numerical simulation in the paper. Comparison of the practicability for the reinforcement of slope with in-situ bored piles and diaphragm walls are performed so as to enhance the stability of the high and steep slope. The safety factor of the slope due to rockmass excavation both inside the exit portal and beneath the bridge abutment of the bridge-tunnel combination has been also derived using strength reduction technique. The obtained results show that post tunnel portal is a preferred structure to fit high and steep slope, and the surrounding rock around the exit portal of the tunnel on the high and steep mountainous slope remains stable when rockmass is excavated both from the inside of the exit portal and underneath the bridge abutment after the slope is reinforced with both bored piles and diaphragm walls. The stability of the high and steep slope is principally dominated by the shear stress state of the rockmass at the toe of the slope; the procedure of excavating rockmass in the foundation pit of the bridge abutment does not obviously affect the slope stability. In-situ bored piles are more effective in controlling the deformation of the abutment foundation pit in comparison with diaphragm walls and are used as a preferred retaining structure to uphold the stability of slope in respect of the lesser time, easier procedure and lower cost in the construction of the exit portal with bridge-tunnel combination on the high and steep mountainous slope. The results obtained from the numerical analysis in the paper can be used to guide the structural design and construction of express railway tunnel portal with bridge-tunnel combination on high and abrupt mountainous slope under similar situations.

A Comparative and Parametric Study of Slope Stability Using a Probability-based Method in Railway Slope (철도 사면에서 확률론적 기법을 이용한 사면안정성 매개변수 비교연구)

  • Choi, Chan-Yong;Kim, Ju-Yong;Eum, Ki-Young
    • Journal of the Korean Geosynthetics Society
    • /
    • v.11 no.4
    • /
    • pp.17-25
    • /
    • 2012
  • In this study, it was carried out reliability analysis and slope stability analysis in a standard cross-sectional embankment on high speed railway. It was confirmed that changing tendency of safety factor with various parameter of each soil materials properties and trends of the probability of failure according to the reliability index. The results have shown that a safety factor were relatively large affected an cohesions and internal friction angle of soil compared to the unit weight of soil. Also, most of the standard cross-sectional embankment in high speed railway was generally evaluated the level of below average (below average) by the reliability analysis according to criterion in US. Army but the 12m height of dry embankment case was shown bad condition as Poor.

Rail Transport Operation Control for Railway Embankment under rainfall (강우시 성토사면의 열차운전규제기준)

  • Kim, Hyun-Ki;Shin, Min-Ho;Choi, Chan-Yong
    • Proceedings of the Korean Geotechical Society Conference
    • /
    • /
    • pp.225-232
    • /
    • 2009
  • Infiltration of rainfall causes railway slopes to be unstable and may result in failure. Basic relationship between the rainfall and stability of railway embankment is defined to analyze its stability by rainfall. An experimental study for defining of infiltration rate of rainfall into slope is conducted in the lab. The results of Rainfall infiltration show that rainfall infiltration is not equal to infiltration as like reservoir because rate of rainfall infiltration is controlled by slope angle. Based on these results, boundary condition of rainfall is altered and various numerical analysis are performed. The variation of shear strength, the degree of saturation and pore-water pressure for railway slope during rainfall can be predicted and the safety factor of railway slope can be expressed as the function of rainfall amount, namely rainfall index. And suggested rainfall index is compared with the rail transport operation control which is used in KORAIL. It is judged that this rainfall index can be a good tool for the rail-transport operation control.

  • PDF

Numerical Analysis Considering Rainfall Infiltration For the Railroad adjacent Slopes (강우침투를 고려한 철도 연변사면의 안정성 해석)

  • Kim, Min-Seok;SaGong, Myung;Kim, Soo-Sam
    • Proceedings of the Korean Geotechical Society Conference
    • /
    • /
    • pp.687-696
    • /
    • 2006
  • Slope failure triggered by rainfall produces severe effects on the serviceability and stability of railway. Therefore slope stability problem is one of the major concerns on the operation of railway. In this study we collected rainfall data when and where slope failures were observed. The collected data show that the range of cumulative rainfall is from 150 to 500mm and the rainfall duration is about 3 to 24 hours. By using the collected rainfall information, slope stability analysis considering infiltration was carried. The analyses employs multiple sliding surfaces to find the minimal factor of safety in the infinite slope condition. This approach show more reasonable results than the results from analysis following the design code which assumes that groundwater level and the slope surface are equal.

  • PDF

A proposal and application of critical rainfall curve for disaster prevention of railway slopes due to rainfall(I) (강우에 의한 철도토공사면 방재를 위한 한계우량식 산출 및 적용(I))

  • 김현기;박영곤;신민호
    • Proceedings of the KSR Conference
    • /
    • /
    • pp.437-442
    • /
    • 2001
  • 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.

  • PDF

Analysis of Slope Stability Using GIS in the Northern Area of Chungju Lake (지구정보시스템을 이용한 충주호 북부 지역의 사면 안정 평가)

  • 문상기
    • Economic and Environmental Geology
    • /
    • v.33 no.1
    • /
    • pp.51-59
    • /
    • 2000
  • As a part of natural hazard assessment, regional slope stability analysis was conducted using Geoscientific Information System (GIS) in the northern area of Chungju Lake. Selected factors which affect the slope stability in the study area were lithology, soil, density of lineament, groundwater level, dip of slope, aspect of slope, and geological engineering properties. Geological structural domains were determined by collected data of joint orientation from about 200 sites in order to produce a slope instability map. Potential type of failure and its direction could be expected through the domains. And a slope instability map was produced, comparing the representative orientations of the domains with the orientations of the slopes which were made through TIN module in ARC/INFO. Under the consideration of environmental geological characteristics of the study area, rating and weighting of each factor of slope stability analysis were decided and spatial analysis of regional slope stability was couducted through overlaying technique of GIS. The result of areal distribution of slope stability showed that the most unstable area was the area between Mt. Pudae and Mt. Jubong, and the northern area of the railway station, Samtan.

  • PDF

Slope Stability Analysis Considering Multi Failure Mode (다중파괴모드를 고려한 사면안정해석)

  • Kim, Hyun-Ki;Kim, Soo-Sam
    • Journal of the Korean Society for Railway
    • /
    • v.14 no.1
    • /
    • pp.24-30
    • /
    • 2011
  • Conventional slope stability analysis is focused on calculating minimum factor of safety or maximum probability of failure. To minimize inherent uncertainty of soil properties and analytical model and to reflect various analytical models and its failure shape in slope stability analysis, slope stability analysis method considering simultaneous failure probability for multi failure mode was proposed. Linear programming recently introduced in system reliability analysis was used for calculation of simultaneous failure probability. System reliability analysis for various analytical models could be executed by this method. For application analysis for embankment, the results of this method shows that system stability of embankment calculate quantitatively.