• Geotechnical Engineering
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• v.14 no.6
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• pp.73-80
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• 1998

In order to identify clay minerals in the soft ground, which has been deposited along the coastline of the Korean peninsula, 14 samples have been taken at different locations and then X-ray diffraction analysis is carried out for them. It is known from the analysis that the various kinds of clay minerals mixed with different portions exist in the soft ground, but halloysite is not traced in any samples. It is featured regionally that kaolinite and illite are found in the western coast and the southern coast. Montmorillonites exists only in the western coast. This feature of regional occurrences can be explained with the help of geology of the region. Activities determined from physical properties of the soils do not coincide with those of clay minerals identified from X-ray diffraction analysis.

• Proceedings of the Korean Geotechical Society Conference
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• 2000.11a
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• pp.217-222
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• 2000

An understanding of the behaviour of soft clay soils is important in a large number of civil engineering applications, including dredging operations, land reclamation and slurry management such as disposal and storage. Although the details of the behaviour depend on parameters such as the soil mineralogy, the pore water chemistry, the organic content and the microbiology, there are general features that are typical in many cases. The purpose of this paper is to present and discuss some of evaporation and desiccation observed in laboratory experiments under controlled conditions. Desiccation of dredged material is basically removal of water by evaporation which is controlled by weather and material type, etc. This study shows that (1) solar radiation, (2) wind velocity, (3) material depth, (4) trench depth are important factors in desiccation of dredged ultra soft clay.

• Journal of the Korean Geosynthetics Society
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• v.8 no.1
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• pp.19-24
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• 2009

In this paper, a series of numerical analyses on soft clay ground improved by PVD were carried out, in order to investigate the consolidation promotion effect considering PVD width and surcharge pressure. In the numerical analyses, an elasto-viscoplastic three-dimensional consolidation finite element method was applied, in which the applicability of numerical analyses could be confirmed comparing with consolidation behavior simulated at the laboratory. And, through the results of the numerical analyses, consolidation behaviors of soft clay ground with elapsed time was elucidated, together with the effects of PVD width and surcharge pressure.

• Geotechnical Engineering
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• v.9 no.2
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• pp.55-64
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• 1993

When earth structures such as dykes or embankments are constructed on very soft clay foundation, unexpectedly large deformations of earth structures as well as clay foundation are encountered during and after construction. The final constructed section is composed of a portion of embankment above the existing ground level and that which penetrated into the soft foundation soil. This study is aimed to correctly estimate the shape of earth structures which penetrate some depth into the soft clay foundation. In this study the methods to predict penetration depth and deformation shape of embankment section after dumping of construction material. Model tests were carried out to prove the developed theory and FEM analysis. And when the mat is added, reinforcement effect was markedly noticed.

• Proceedings of the Korean Geotechical Society Conference
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• 2008.10a
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• pp.1144-1156
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• 2008

In this paper, heaving phenomenon is analyzed by laboratory tests. A laboratory test is consist of building soft clay foundation in plane-strain soil tank, construction of retaining wall, and excavation work. And range of shear strain, and destruction shape about soft clay foundation is compared, and analyzed with results of proposal formula. Using this study, safety factor is suggested for heaving phenomenon in the construction of wall on the soft clay. Actual theory is suggested by this suggested safety factor. There are various proposal formula for heaving phenomenon. For example, Terzaghi & Peck, Tschebotarioff, Bjerrum & Eide(Experience formula) and so on. Terzaghi & Peck's proposal formula is chosen, compared with laboratory test's result and analyzed in this study. A soft clay used in study is assumed homogeneous. A Depth of foundation is enough to observe shear strain by heaving phenomenon. Retaining wall is enough hard not to have vertical displacement.

• Proceedings of the Korean Geotechical Society Conference
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• 1997.10a
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• pp.373-382
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• 1997

• Proceedings of the Korean Geotechical Society Conference
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• 1998.10a
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• pp.397-404
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• 1998

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.13 no.4
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• pp.282-289
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• 2001

This study analyzed the relationship between the physical properties of soil and the compression index of the soft clay in Gyungnam coastal region. Tests of physical and mechanical properties of soil have been carried out under the undisturbed condition at 82 Gimhae, 18 Jinhae and 27 Geojespecimens. The result showed that Terzaghi & Peck's empirical equation of the compression index were not applicable. The compression index of soft clay in Gyungnam coastal region was correlated with the water contents, the liquid limit and the initial void ratio. Among these, the initial void ratio showed the highest correlation with the compression index of soft clay in Gyungnam coastal region and the relationship is shown in the following. (1) The compression index of soft clay in Gyungnam coastal region is represented as follows: $C_c=0.74(e_o-0.7$ (2) The relationship between compression index and the swelling index in Gyungnam coastal region is represented as follows: $C_s=(1/8-1/15)C_c$.

• Journal of the Korean GEO-environmental Society
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• v.25 no.4
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• pp.5-12
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• 2024

In the case of creating a site in the reclaimed land (public waters), due to the nature of the coastal sedimentary ground, large-scale construction materials are required, It is necessary to utilize soft clay, which is inevitably generated during construction of the complex, as a fill material in terms of resource recycling and economic aspects (reducing the amount of embankment required). In this study, changes in the consolidation characteristics of cut-out disturbed soft clay due to the recycling of soft clay soil were identified, and a consolidation settlement design plan was proposed. Through the results of the consolidation test of the study site, the change in consolidation characteristics (compression index reduction, precede load uncountable) due to disturbance (cutting) was confirmed, the method of calculating (consolidation settlement) the filling clay layer as the composite target layer (consolidation target layer, loading load layer) was analyzed as a result consistent with the actual behavior.

• Magazine of the Korean Society of Agricultural Engineers
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• v.13 no.4
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• pp.2445-2455
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• 1971

One-dimensional Consolidation tests with pore pressure measurement were caried in the ANTE-US consolidometer in order to investigate the effects of loading conditions on consolidation behavior of the soft clay. Undisturbed specimens of a sensitive clay were loaded in load-increment ratioes 0.5, 1.0 and 2.0, and load increment duration of 1, 6, 12, 24 and 48 hours with the application of 40 psi of back pressure. There is no significant effect of load-increment ratio on compression-pressure relationship, but the test with one-hour load increment duration doesn't represent the same results of the standard consolidation test in the sensitive clay.