• Proceedings of the Korean Geotechical Society Conference
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• 2009.09a
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• pp.524-528
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• 2009

An influence factors for soundness evaluation of river levee include resistibility and embankment for piping of ground consisting embankment in case piping, permeability coefficient of ground, height of embankment, the width of crest, material characteristics of embankment and foundation ground, shape of embankment slope, an influence for penetration of rainfall or river water in case slope stability. In this study, it was operated a feasibility investigation of existing design result, stability evaluation for permeability coefficient use and permeability coefficient change of foundation ground to investigate an influence in line with permeability coefficient change for result of river levee penetration analysis. The evaluation results of influence factors, the permeability coefficient used in design and it was evaluated influence in safety factor of piping. After the evaluation of influence factors, the permeability coefficient used in the design appears with the fact that differs in a design report about same soil, Accordingly, the stability investigation of embankment by application of literature data can affect stability evaluation results by change factors like a permeability coefficient, void ratio. It should be certainly used material properties by a test in soundness evaluation of river levee.

• Journal of the Korean GEO-environmental Society
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• v.2 no.1
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• pp.57-65
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• 2001

In this study, the seepage behavior and the stability of the extension embankment were estimated for three cases the permeability coefficient of an extension part and the rising velocity due to the rainfall of flood period. In parallel flow condition, the unstability of the slope due to embankment erosion was examined by analyzing the variation of seepage line by the seepage modeling tests and FEM analysis, and the stability of the embankment slope accompanied by the sudden rise of the water level after the flood. The seepage behavior of extension embankment indicates that the larger permeability of the extension part the longer initial seepage distance, and the exit point from embankment slope is gradually increased, and then shows unstable seepage behavior that occurs a partial collapse as safety factor decreases with time. It is because of the increment of exit points due to variation of seepage line and rising velocities of water level. Also, the collapse aspect of embankment slope shows that the increment rising velocities of water level causes the increment collapse height and depth.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.28 no.2C
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• pp.133-141
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• 2008

Theoretical analysis are developed to estimate the load transfer by soil arching in geosynthetic-reinforced and pile-supported(GRPS) embankment systems. According to the results of analyses, the efficiency of embankment pile systems increases when the geosynthetics are installed with piles. Especially the increment of efficiency is more remarkable in the low embankment height, where soil arching can not be fully developed. The factors affecting the load transfer in GRPS embankment systems are the pile spacing, the height and properties of embankments, and the strength of geosynthetics. The efficiency decreases with increasing the pile spacing, while it increases with the height and internal friction angle of embankment fills, and the strength of geosynthetics. These results of analyses show the proposed analysis method is resonable to estimate the soil arching in GRPS embankment systems.

• Proceedings of the Korean Geotechical Society Conference
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• 2003.06a
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• pp.13-22
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• 2003

Train speed and infiltration of rainfall causes railway embankment to be unstable and may result in failure. Therefore, the variation in the safety factor of railway embankment should be analyzed as the function of rainfall intensity, rainfall duration, and train speed and the study is accomplished using numerical analysis program. Based on unsaturated soil engineering, the variables in the shear strength function and permeability function are also defined and used for the numerical model for evaluation of railway embankments under rainfall. As a result of the study, in order to secure the safety of train under rainfall, the variation in the safety factor of railway embankment is predicted as the function of rainfall intensity, duration time and the train load as a function of train speed. It is possible to ensure the safety of train under rainfall. Thereafter, the feasibility of the rail-transport operation control with engineering basis was established.

• Journal of the Korean Society for Railway
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• v.3 no.4
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• pp.203-212
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• 2000

In order to evaluate the stability of railway embankment 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 maximum hourly rainfall during 24 hours before failure caused the collapse of railway embankment and could be used estimate the stability of railway embankment. From the result of application to a collapse example, the evaluaton method by critical rainfall curve is satisfactory.

• Proceedings of the KSR Conference
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• 2009.05a
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• pp.1519-1524
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• 2009

Construction of high-speed concrete track embankments over soft ground needs many of the ground improvement techniques. Drains, surcharge loading, and geosynthetic reinforcement, have all been used to solve the settlement and embankment stability issues associated with construction on soft soils. However, when time constraints are critical to the success of the project, another measures should be considered. Especially, since the design criteria of residual settlement is limited as 30mm for concrete track embankment, it is very difficult to satisfy this allowable settlement by using the former construction method. Pile net method consist of vertical columns that are designed to transfer the load of the embankment through the soft compressible soil layer to a firm foundation and one or more layers of geosynthetic reinforcement placed between the top of the columns and the bottom of the embankment. In this paper, three cases with different embankment height and number of geosynthetic reinforcement, were studied through FEM analysis for efficient use of pile net method.

• Geomechanics and Engineering
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• v.31 no.6
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• pp.637-651
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• 2022

The seismic design of embankment dams requires more comprehensive studies to understand the behaviour of dams. Deformations primarily control this behaviour occur during or after earthquake loading. Dam failures and incidents show that the impacts of deformations should be reviewed for existing and new embankment dams. Overtopping erosion failure can occur if crest deformations exceed the freeboard at the time of the deformations. Therefore, crest settlement is one of the most critical deformations. This study developed empirical formulas using Gene Expression Programming (GEP) based on 88 cases. In the analyses, dam height (H_d), alluvium thickness (H_a), the magnitude-acceleration-factor (MAF) values developed based on earthquake magnitude (Mw) and peak ground acceleration (PGA) within this study have been chosen as variables. Results show that GEP models developed in the paper are remarkably robust and accessible tools to predict earthquake-induced crest settlement of embankment dams and perform superior to the existing formulation. Also, dam engineering professionals can use them practically because the variables of prediction equations are easily accessible after the earthquake.

• Magazine of the Korean Society of Agricultural Engineers
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• v.37 no.5
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• pp.101-110
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• 1995

The use of geotextile as reinforced materials in Soil structures has become widespread throughout the world. Geotextile reinforcement has been used in retaining walls, slope of embankment and especially soft foundation, etc. In the past, however, its design and construction have been performed empirically. In this study, to investigate of the effect of geotextiles reinforced slope of the embankment on a very soft foundation, a limit equilibrium analysis program calculating the safety factor of embankment on very soft foundation was developed. The study was focussed on such factors as type of geotextile, tensile strength, amount of reinforcement, and inclination of embankment. And the 4imit equilibrium analysis program was written on the basis of Low's slope stability theory with some modification. The following conclusions were drawn from this study. (1) The orientation of reinforcement can be assumed either horizontal or tangential to the slip circle. The factor of safety with tangential reinforcement is larger than that with the horizontal reinforcement. (2) In general, the factor of safety increases, as the slope reduces. However, it is preferable to use geotextiles with higher tensile strength rather than to reduce the slope of the embankment, because it is difficult to adjust the slope as desired. (3) The factor of safety obtained by numerical computation is affected only by the tensile strength, but not by the type of the geotextile.

• Journal of the Korean earth science society
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• v.29 no.6
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• pp.447-453
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• 2008

Recently, the electrical DC survey has frequently been performed to assess the safety of embankment. This study showed that the damaged section of embankment could be appropriately detected by the survey only when the three dimensional effect was correctly considered. The shape of the three dimensional embankment was numerically implemented, and a proper modeling was performed to confirm the effect by analyzing the apparent and inverted true resistivity. Then, the field work was carried out. The three dimensional interpretation distinguished the erroneous weak zones from the geometrical artifact, and the embankment was ensured as safe both by the additional survey performed in rainy season and the partial excavation for direct observation.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.14 no.5
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• pp.1253-1263
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• 1994

The stability of the embankment is depended upon the location of seepage line. As the seepage flow occurs in the embankment, the slope of the embankment loses its stability. Of particular interest is the stability following a rapid change of embankment level. The variation of seepage line in the embankment model according to flow velocity was investigated. In addition to this non-steady state flow in embankment by a fluctuation of water level is discussed. The experimental model was construction with slopes of 1 : 2.5 and flow velocity is turned from 60 cm/sec~90 cm/sec. Analysis of the experimental results, the seepage line is influenced by flow velocity and coefficient of permeability.