• Ocean and Polar Research
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• v.25 no.spc3
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• pp.385-392
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• 2003

A new type of soft ground breakwater was recently developed, which does not need ground improvement because of light weight and structural characteristics. The various studies about consolidation settlements and lateral behavior of proposed soft ground breakwater have been conducted. But, the systematic investigations on the construction performance and long-term settlements of new type breakwater has not been accomplished. In this study, construction simulation of soft ground breakwater with soil box model test and experiments of the long-term wave loaded breakwater were performed. The results of test shows that it is possible to compensate differential settlements by dead loading and/or suction pressure, and to reduce the consolidation settlements by preloading method. It was also found that the vertical and lateral displacements of long-term wave loaded breakwater were negligible.

• Proceedings of the Korean Geotechical Society Conference
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• 2002.03a
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• pp.431-438
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• 2002

Reclaimed coastal areas for the construction of ports and harbors are in general subjected to strong possibility of liquefaction. In this research, a new method for liquefaction hazard microzonation based on liquefaction settlements was developed. Severity of liquefaction hazard was defined by liquefaction settlements obtained from the method proposed by Tokimatsu and Seed. 10 coastal areas, representing typical geological and geotechnical characteristics of Korean ports and harbors, and 3 real earthquake records for site response analysis were selected. From this research, liquefaction settlement criteria is adapted as a new quantitative index for the liquefaction hazard microzonation. Liquefaction settlements were also compared with LPI (Liquefaction Potential Index), obtained from the assessment of liquefaction potential based on the modified Seed and Idriss's method. As an example, 2 and 3 dimensional liquefaction hazard microzonations of Pusan port and harbor area were mapped by overlapped liquefaction settlement contours.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.3
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• pp.1770-1777
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• 2014

Coastal settlements have a diversity of tangible or intangible local assets and are environmentally sensitive areas. The value of tangible or intangible local assets is often overlooked and there is no enough consideration for the inhabitants who have a various and acute stake in the development process of coastal settlements. The development of coastal settlements without consideration for the local circumstance, resident's needs, and local characteristics makes it difficult to achieve sustainable regeneration. There are also alienation, conflicts, and the loss of a authentic sense of place because of physical oriented development without regard to the social, economic, and cultural aspects. This research defines the components and types of coastal settlements and draws the characteristics of them around the fishery ports in Busan in the aspect of sustainable regeneration. It will be the important methods for an integrated regeneration including not only spatial and physical regeneration but also social and economic regeneration which has the preservation of local culture with living conditions, local economy activation, and community building. It will also provides the bases of sustainable development, attractiveness, and competitiveness of coastal settlements.

• Proceedings of the Korean Geotechical Society Conference
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• 2004.03b
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• pp.219-226
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• 2004

We measure subsidences occurred in a reclaimed coastal land, Noksan industrial complex, by using JERS-1 SAR (1996-1998) and RADARSAT-1 SAR (2002-2003) dataset. SAR with a high spatial resolution (about several or several tens meter) can reveal the two-dimensional distribution of settlement that would be bardly estimated from in situ measurements. The DInSAR results show significant deformation signal associated with soil consolidation. Accuracy of the settlements estimated by 2-pass differential interferometry (DInSAR) is evaluated using the measurements of settlement gauge. A two-dimensional subsidence map is constructed from 7 qualified pairs. Comparing the JERS-1 radar measurements with the ground truth data yields the correlation coefficient of 0.87 (RMSE of 1.44 cm). The regression line shows the gradient of 1.04 and intercepts close to the origin, which implies that the unbiased settlement can be measured by DInSAR technique. The residual settlements are also detected from RADARSAT-1 pairs. The extent and amount of the settlements are matched well with ground truth data.

• Proceedings of the Korean Society of Coastal and Ocean Engineers Conference
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• 2002.08a
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• pp.274-279
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• 2002

최근 국내에서 건설되고 있거나 계획 중인 신항만의 대부분은 우리나라의 대표적인 연약지반 지역에 위치하고 있어 항만 건설에 있어 경제성 및 시공성에 많은 어려움을 겪고 있으며, 방파제의 경우에도 연약지반 위에서 안전성을 확보하기 위해 엄청난 비용을 투입하여 지반계량을 실시하고 있다. 이러한 문제를 해결하기 위하여 경제적이면서도 안전성을 확보할 수 있는 새로운 형식의 연약지반용 방파제의 개발이 시도되고 있다(권오순 등.2001 ; 권오순 등, 2002). (중략)

• Journal of the Korean Geotechnical Society
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• v.24 no.10
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• pp.93-103
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• 2008

For conventional gravity type offshore structures constructed on the soft ground, which is located on the western and/or southern Korea, the excessive consolidation settlements are caused by the self-weight of the structures and so additional ground treatment methods are generally needed. Several types of improved foundation systems utilizing buoyancy applicable to even the soft ground were introduced for economical and efficient design of the offshore structure. In this study, a series of numerical simulations on the consolidation and lateral behaviors of breakwaters with the improved foundation systems utilizing buoyancy were carried out. From the results of numerical simulations it is found that the foundation systems utilizing buoyancy are efficient for reducing the maximum consolidation settlements without reducing lateral safety.

• Proceedings of the Korean Geotechical Society Conference
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• 2008.10a
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• pp.1712-1716
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• 2008

Performance of ground improvement project using prefabricated vertical drains of condition, in which approximately 10m dredged fill overlies original soft foundation layer in the coastal area has been conducted. From field monitoring results, excessive ground settlement compared to predicted settlement in design stage developed during the following one year. In order to predict the final consolidation behavior, recalculation of consolidation settlements and back analysis using observed settlements were conducted. Field monitoring results of surface settlements were evaluated, and then corrected because large shear deformation was occurred by construction events in the early stages of consolidation. To predict the consolidation behavior, material functions and in-situ conditions from laboratory consolidation test were re-analyzed. Using these results, height of additional embankment is estimated to satisfy residual settlement limit and maintain an adequate ground elevation. The recalculated time-settlement curve has been compared to field monitoring results after additional surcharge was applied.

• Proceedings of the Korean Geotechical Society Conference
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• 2008.03a
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• pp.300-310
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• 2008

A series of numerical simulations on the several types of breakwaters on the foundation systems utilizing buoyancy were carried out in plane-strain conditions using the modified Cam-Clay model and the Biot's consolidation theory. Improved foundation system by the replacement of original ground with light weighted material, expandable poly-styrene (called below EPS) and several foundation systems with buoyant cells were used. From the results of numerical simulations we found that the foundation systems utilizing buoyancy are efficient to reduce the maximum consolidation settlements without reducing lateral safety.

• Proceedings of the Korean Geotechical Society Conference
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• 1999.02a
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• pp.23-35
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• 1999

Although the purpose of dredging in the past was merely as a means of lowering the water level, presently land reclamation from dredged fill is of greater interest. From an economical standpoint, due to the difficulties in acquiring landfill for coastal projects, there is a growing trend toward simply using easily obtainable marine clay for use as fill. But because the ground formed by dredged fill has but low strength and is accompanied by large settlements, it is important that the engineering characteristics be fully investigated. In order to use dredged Masan marine clays as fill material, the engineering characteristics have been studied in this paper.

• Journal of the Korean Geosynthetics Society
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• v.8 no.4
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• pp.9-17
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• 2009

This research was intended to verify the stability of landfill final cover using SRSL(Self Recovering Sustainable Liner) with regard to differential settlements due to the degradation of waste and so on in a waste landfill. Numerical analysis was performed using FLAC 2D software program with input parameters based on soil characteristic tests and reference data after the blank was designed in order to represent the decomposition condition of waste. The maximum settlement of landfill cover was calculated to investigate the structural stability of landfill cover with the different condition of settlement width, settlement depth, and number of differential settlements. The allowable maximum deformation rate of SRSL, which was calculated using field permeability tests, was 6 mm. The analysis showed that SRSL was stable in case of a differential settlement width not exceeding 24.5% of total cover width.