• Journal of the Korea institute for structural maintenance and inspection
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• v.9 no.4
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• pp.202-208
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• 2005

In Korea it tends to rely on foreign standards for the stability management of the embankment slope on the soft clay layer. The Matsuo-Kawamura's method, the Kurihara's method, the Tominaga- Hashimoto's method and the Shibata-Sekiguchi's method are generally employed at site. In this study these slope stability methods are investigated and the applicability of the stability management methods is evaluated through numerical analysis. It is evaluated that stability is overestimated to some degree by the Matsuo-Kawamura method. According to the result by the Tominaga-Hashimoto method there is some risk of sudden failure. This implies that the careful attention is necessary for the management of monitoring the field data. Even though the stability tends to be underestimated by the Kurihara's method, however, it is estimated that this method is applicable to the field when the probable uncertainty at site is considered. For the Shibata-Sekiguchi's method, there is some difficulties in determining the failure index for the practical application, it is considered as safe when the existing estimated failure index is greater than ${\Delta}_q/{\Delta}{\delta}$. In this study, however, it is evaluated to be safe as well when ${\Delta}_q/{\Delta}{\delta}$ to load shows the tendency of constant increase.

• Korean Journal of Agricultural Science
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• v.25 no.2
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• pp.260-270
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• 1998

The field tests were performed to suggest the rational method for stability evaluation of soft clay. The behavior of settlement-displacement obtained by field monitoring system was to compare and analyze the results of the observationed method, and to investigate the complex behavior of soft clay with filling height. The results of this study are summarized as follows. 1. The horizontal displacement was suddenly increased when physical properties of soft clay showed maximum values and the part of the turning point. The values of these properties were available to the fundamental data for stability evaluation. The shear deformation appeared that difference of the horizontal displacement was maximum values. 2. Although the stability of embankment by step filling showed the unstable part over the failure standard line, the embankment was confirmed stable. So the evaluation of the stability of embankment is reasonable to use the inclination of curve than failure standard line. 3. The horizontal displacement and relative settlement were increased as same ratio at improvement ground. Estimation of shear deformation using Terzaghi's modified bearing capacity should consider the relations of embankment load and undrained shear strength at nonimprovement ground, and minimum safety factor is recommended to use larger than 1.2. 4. Excess pore water pressure was increased with increasing of filling height and decreased with maintain the filling height. The embankment was unstable when filling height was exceed the evaluation standard line, and the behavior of excess pore water pressure and horizontal displacement could use as a standard of judgement of the filling velocity control because their behavior were agree with each other.

• Proceedings of the Korean Geotechical Society Conference
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• 1993.06b
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• pp.45-98
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• 1993

• Proceedings of the Korean Geotechical Society Conference
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• 1995.06b
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• pp.15-34
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• 1995

The deformations of ground due to the embankment on the soft clay affect the stability of embankment. This study compares the result of Korea's measured values with foreign's results. And it examines the irregularity of the soil behavior depending on the characteristics of the ground, and the results can be used as the base data for studying the complex factors on the soft ground. Meanwhile, several problems of applying the conventional methods to the domestic field are also discussed. The purpose of the study is to aid the regulations concerning the safety of the embankment on the soft clay, Especially, consideration of depth of the soft ground, embankment height and stress history, etc. should be added to existing factors of correlation between the lateral displacement and the vertical displacement.

• Journal of the Korean Geotechnical Society
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• v.32 no.3
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• pp.5-13
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• 2016

Stability analysis was conducted to analyze the application of pile-supported embankment to concrete slab track on the soft ground in Korea. Pile efficiency and tension of geosynthetics in accordance with the hight of embankment and the depth of soft soil were carried out by theoretical and numerical methods. Theoretical method predicted more conservatively than the numerical method for all the cases presented herein. The settlement stability is satisfied to allowable criteria of high speed railway in Korea. The pile-supported embankment has great potential for application to soft ground condition.

• Journal of the Korean Geotechnical Society
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• v.28 no.9
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• pp.5-15
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• 2012

Field monitoring data for embankments in thirteen road construction sites at coastal area of the Korean Peninsula were analyzed to investigate the characteristics of lateral flow in soft grounds, to which vertical drain methods were applied. First of all, the effect of the embankment scale on the lateral flow was investigated. Thicker soft soils and lager relative embankment scale produced more horizontal displacements in soft grounds. Especially, if thick soft grounds were placed, the relative embankment scale, which was given by the ratio of thickness of soft ground to the bottom width of embankments, became larger and in turn large horizontal displacement was produced. And also higher filling velocity of embankments induced more horizontal displacements in soft grounds. The other major factors affecting the lateral flow in soft ground were the thickness and undrained shear strength of soft grounds, the soil modulus and the stability number. Maximum horizontal displacement was induced by less undrained shear strength and soil modulus of soft grounds. Also more stability numbers produced more maximum horizontal displacements. When the shear deformation does not develop, the stability number was less than 3.0 and the safety factor of bearing was more than 1.7. However, if the stability number was more than 5.14 and the safety factor of bearing was less than 1.0, the unstable shear failure developed in soft ground. 50mm can be recommended as a criterion of the allowable maximum horizontal displacement to prevent the shear deformation in soft ground, while 100mm can be recommended as a criterion of the allowable maximum horizontal displacement to prevent the shear failure in soft ground.

• Korean Journal of Agricultural Science
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• v.30 no.2
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• pp.164-174
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• 2003

This study was performed to suggest a rational method for the stability evaluation of agricultural reservoir in the very soft ground. The stability methods for agricultural reservoir was used to compare and analyze with various condition by limit equilibrium method. The behavior of settlement-displacement obtained by field monitoring system was used to compare and analyze with various stability methods, and to investigate the applicability of the methods for stability evaluation of agricultural reservoir. The horizontal displacement was abruptly increased when physical properties of soft clay reached its maximum values and therefore, the values of these properties could be used to the fundamental data for stability evaluation. The evaluation of the stability of agricultural reservoir was suggested to use the inclination of curve rather than critical line.

• Journal of the Korean GEO-environmental Society
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• v.3 no.2
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• pp.61-70
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• 2002

This paper presents the engineering property of light weight soil made of soil mixed with recycled Styrofoam and stabilizer. Recycled Styrofoam is widely used for lightweight fill material because it has important geotechnical characteristics which are light, adiabatic, and effective for vibration interception. It is very easy to get the disposal styrofoam. For this study, dynamic compaction test, static compaction test and pH and leaching tests were performed. Based on the test results, it is concluded that the static compaction method is recommened to prevent from crushing materials and pH values of embankment materials are satisfied with these of domestic and RCRA configuration.

• Journal of the Korean Geotechnical Society
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• v.24 no.10
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• pp.105-111
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• 2008

To improve the stability of levee structure, it is required to use good quality fill materials, intensive management, appropriate hydraulic structure and construction of cut-off wall. In particular, the most important factor of levee construction technology is to use bed sediment for its safety. In this study, seepage model test and numerical analysis were performed based on a standard section of levee recommended in the river design standard of korea (2005). The results of test and analysis show that most of the bed soil is a sand (SP in USCS), which does not satisfy the permeability criteria for levee materials ($< k=10^{-3}cm/sec$), thus for the safety of levee it is required to adopt a stabilizing method such as good quality soil mixing, water content control.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.32 no.6C
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• pp.239-247
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• 2012

Some methods were proposed to predict lateral flow due to embankments for road constructions on soft grounds, in which vertical drains were placed. In order to investigate the prediction methods of lateral flow, 200 field monitoring data for embankments in thirteen road construction sites at western and southern coastal areas of the Korean Peninsula were analyzed. For analyzing the relationship between the safety factor of embankment slope and the horizontal displacement in soft grounds where horizontal drain mats were placed, it was reliable to apply the maximum horizontal displacement in soft ground instead of the horizontal displacement at ground surface. The maximum horizontal displacement was developed less than 50mm in fields where the safety factor of slope was more than 1.4, while the one was developed more than 100mm in fields where the safety factor of slope was less than 1.2. In safe fields where the maximum horizontal displacement were developed within 50mm, lateral flow would not happen since shear deformation was not appeared. On the other hand, shear failure would happen in the fields where the maximum horizontal displacement were developed more than 100mm. In such fields, embankments might be continued after some appropriate countermeasures should be prepared. Safe embankments can be performed on soft grounds, in which the stability number is less than 3.0 and the safety factor for bearing is more than 1.7. However, if the stability number is more than 4.3 and the safety factor for bearing is less than 1.2, shear deformation would begin and even shear failure would happen.