• Journal of the Korean Geotechnical Society
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• v.17 no.2
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• pp.95-101
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• 2001

연약한 점토 지반에 안벽을 축조하고 매립하는 경우, 안벽의 기초로서 케이슨 기초공법이 종종 쓰이고 있다. 케이슨 기초는 안벽의 연직 하중을 지지층에 전달할 뿐만 아니라, 매립하중에 의한 연약 점토의 횡방향 소성 유동에 대하여는 매우 효과적인 공법으로 호안공사에서 그 사용 빈도가 증가하고 있는 추세이다. 반면 매립하중에 의해 점토지반에서 장기간에 걸쳐 발생하는 압밀침하에 대해서는 아무런 역할을 하지 못하는 단점이 있다. 따라서 본 연구에서는 기존 케이슨 기초의 배면에 다수의 강관 배수공을 설치함으로써 과잉간극수압의 횡방향 소산을 촉진시켜 압밀 시간을 단축시키는 \"매립측 연약점토 압밀촉진 케이슨 기초공법\"을 제안하였다. 이 새로운 케이슨 공법의 압밀촉진 효과를 분석하기 위하여 2차원 압밀방정식의 해석해를 유도하였다. 연구결과, 등방성 점토에서 압밀촉진 케이슨 사용시 ξ=0.1인 단면에서 평균압밀도 50%, 90%에 이르는 시간이 기존 케이슨을 사용한 것에 비해 각각 약 7배, 3.5배 단축되는 것으로 나타났다. 것으로 나타났다.

• Journal of the Korean Geotechnical Society
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• v.20 no.2
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• pp.67-73
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• 2004

Various researches have been undertaken to develope a method of enhancing consolidation. This study investigated the effect of ultrasonic energy on consolidation through a series of laboratory experiments. The tests were conducted using a specially designed and fabricated equipment which can apply ultrasonic energy on a soil sample directly during a consolidometer test. Clay specimens were prepared from slurry using a centrifuge facility, and test conditions were varied depending on ultrasonic power and treatment time. The results of the study show that the effect of ultrasonic energy on consolidation is significant. The degree of significance varies with the test conditions. It could be concluded that the study showed potential application of ultrasound to reduce consolidation time.

• Proceedings of the Korean Geotechical Society Conference
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• 2004.03b
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• pp.684-691
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• 2004

Various researches have been undertaken to develope a method of enhancing consolidation. This study investigated the effect of ultrasound on consolidation through a series of laboratory experiments. The tests were conducted using a specially designed and fabricated equipments which can apply ultrasonic energy on a soil sample at consolidation test. Specimens were prepared using a centrifuge facility, and test conditions included ultrasonic power and treatment time. The results of the study show that the effect of ultrasonic energy on consolidation is significant. The degree of significance varies with the test conditions. It could be concluded that the study showed potential application of ultrasound to enhance consolidation.

• Proceedings of the Korean Fiber Society Conference
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• 1998.10a
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• pp.307-310
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• 1998

연약지반상에 고속도로 노체를 형성하기 위해서는 다양한 지반개량공법이 적용되며 그 중 가장 보편적인 개량공법이 연직배수를 통한 압밀촉진 공법이다. 이와 같은 압밀촉진공법이 효율적으로 이루어지기 위해서는 연약층 내부에 타입하는 연직배수재의 역할도 중요하지만, 연직배수재를 통해서 상승하는 압밀수를 신속히 제체 밖으로 배출시킬 수 있는 수평배수기능도 매우 중요하다. (중략)

• Proceedings of the KAIS Fall Conference
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• 2008.05a
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• pp.139-141
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• 2008

최근 우리나라는 국토면적을 넓히기 위하여 많은 지역에 준설 및 매립 공사를 수행하고 있다. 준설 및 매립공사 시 주재료로 사용되는 해성점토는 매립 초기에 매우 연약한 지반을 형성하게 된다. 이에 빠른 구조물 시공을 위하여 대상지반의 압밀을 촉진시키는 다양한 공법이 활발히 연구되고 있다. 본 연구는 새로운 압밀촉진 공법개발을 위한 기초시험으로써 초음파 에너지를 연약지반 처리에 활용하고자 자체 고안된 초음파 발생장치를 적용하여 소규모 및 대형시험을 수행하였다. 시험에 사용된 연약 지반 점토시료는 시험조건의 일관성을 유지하기 위하여 자체개발한 원심력 시료 성형기를 사용하였다. 초음파 적용에 따른 압밀시험결과 매우 큰 압밀량의 증가를 확인할 수 있었으며 대형 시험의 경우에도 빠른 간극수압의 소산을 확인 할 수 있었다. 연구결과 초음파가 점토의 압밀시간을 단축시키는데 효과가 크다는 것을 볼 수 있었고, 차후 초음파를 통한 다양한 압밀촉진공법이 개발될 수 있다는 가능성을 확인 할 수 있었다.

• Journal of the Korean Geotechnical Society
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• v.19 no.4
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• pp.7-14
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• 2003

This study has investigated the feasibility of caissons for accelerating consolidation (C.A.C.) constructed in clays with anisotropic permeability by improving the former study on C.A.C. in isotropic clays. Analytical solutions for excessive pore water pressures of two-dimensional consolidation equation and average degrees of consolidation with varying time factors have been provided by considering anisotropic permeability. With varying anisotropic permeability ratios of 5, 10, and 50, consolidation times required for reaching the average degree of consolidation of 90% for C.A.C. at the section of $\xi$=0.1 are shorter than those for conventional caissons by 8, 13, and 47 times, respectively. C.A.C. is more effective in reducing consolidation time as anisotropic permeability ratio increases. This study provides also plots for average degrees of consolidation versus the width to depth ratios of analyzed sections and permeability ratios, which will enable engineers to determine easily average consolidation settlements.

• Journal of the Korean GEO-environmental Society
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• v.13 no.5
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• pp.13-24
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• 2012

In this study, the in-situ model test has been conducted and used to estimate and analyze consolidation behavior of the ground by using the miniature test that reconstructs economically geotechnical behavior of in-situ full scale structure. To analogize the relation among effective stress, void ratio and coefficient of permeability at the self-weight consolidation stage, the low stress seepage consolidation test has been conducted and the involution function of constitutive equation had been obtained from the result of the curve fitted seepage consolidation test result. As a result of the numerical analysis that had been conducted on the representative section using a constitute equation, final settlement was similar with those of self-weight consolidation of the centrifugal model test. But, it was more or less smaller. It seems that these trends are caused by the difference between estimated values.

• Journal of the Korean Geosynthetics Society
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• v.8 no.4
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• pp.35-40
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• 2009

In this paper, a series of laboratory chamber tests was carried out to evaluate promoting consolidation of a porous concrete pile fabricated with recycled aggregates (RAPP) method for soft ground improvement. Performing the laboratory chamber tests for the RAPP, characteristics of the surface settlement with time and the consolidation time were compared with those of SCP and GCP provided by You (2009) under the same experimental condition. In addition, the experimental results were compared with the numerical analysis in this study. As a test result, the effects for settlement reduction in both the primary and the secondary consolidation and promoting consolidation by RAPP were prominent comparatively.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.9 no.4
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• pp.1039-1042
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• 2008

Dredged fills have been widely used to secure a land for the engineering activities. Before the useful application of the area, the soils should be consolidated to acquire the aquate shear strength. Several research projects have attempted to develop a method fur accelerating the consolidation of soft clay. Our study examined the effect of ultrasonic energy on the consolidation of soft clay, Tests were conducted using specially designed and fabricated equipment that was capable of directly applying ultrasonic energy to soil samples during consolidation tests. The specimens were prepared from slurry using a centrifuge facility, and tests were conducted at various levels of ultrasonic power and treatment time. The study showed that ultrasonic energy had a considerable effect on consolidation time, suggesting that ultrasound can be used to reduce the consolidation time of soft clay.

• Journal of the Korean Geotechnical Society
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• v.25 no.12
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• pp.37-45
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• 2009

Dredging and reclamation which have been conducted steadily for creation of new coastal area have the demerit of taking a long time. Hence, a lot of researches on acceleration of self-weight consolidation have been proceeding continuously. In this paper, 30 cases of laboratory self-weight consolidation tests were conducted to understand the application of PDF method, one of the self-weight consolidation acceleration methods, to domestic dredged soils. Acceleration effect of self-weight consolidation was confirmed through comparison and analysis of completion times and settlements of self-weight consolidation for none installed case and 4 kinds of common used PBD installed cases. As a result of the tests, installation of PBD before filling is effective for time reduction of self-weight consolidation.