• 한국지반공학회:학술대회논문집
• /
• 한국지반공학회 2008년도 추계 학술발표회
• /
• pp.672-679
• /
• 2008

During recent years, the large soft ground improvements very rapidly increase with industrial development and it is the types and scales of structure that is enlarged by degree. Then, we must enter construct equipment to improve soft ground and we fulfilled works by carrying out soft clay soil to gain trafficability for them. For improving the soft ground, we lay geotextile on soft clay ground and fill the filter sand that can drain the pore water. Then, we landfill cover soil for come by trafficability of construction tools. Ater that we penetrate vertical drain for dehydration through soft ground. there are very complicated works. For these reason we suggest the methods of soft ground improvement constructions.

• 한국건축시공학회지
• /
• 제1권1호
• /
• pp.160-168
• /
• 2001

This study aims at the development of computer program for the deformation analysis of soft ground, and using this computer program, study the constraint effect of deformation heaving, lateral displacement of the soft ground reinforced with improvement of soft ground up to hard strata, under intact state(natural). The following results are obtained. 1. Improvement of soft ground to the hard strata works well against the settlement of neighboring ground. 2. the larger the rigidity or width of improvement of layer to hard strata is, the less settlement occurs. 3. Improvement of soft ground to the hard strata is of no use.

• 한국지반공학회:학술대회논문집
• /
• 한국지반공학회 2002년도 가을 학술발표회 논문집
• /
• pp.553-560
• /
• 2002

The improvement effect of soft ground is estimated by unconfined strength mainly. The unconfined strength of solidification agent treated soil is likely to vary with ununiformed mixing ratio and water content change of in-situ ground place by place. So, it is unreasonable to apply a solidification agent mixing ratio obtained from laboratory test results on all over the soft ground. In this study, it was analysed how the unconfined strength would be effected by the water content of soft ground. For this study, a series of unconfined compressive tests are peformed on various water content soil samples. The test results showed that the strength was fallen to 30∼80% by two times increase of water content approximately, This means that strength of solidification agent treated soil is influenced greatly by water content of raw soft ground and mixing ratio of solidification agent. It was suggested that the method how to decide the mixing ratio with soft ground water content.

• 한국지반신소재학회논문집
• /
• 제19권3호
• /
• pp.35-44
• /
• 2020

본 연구에서는 연약지반에 설치된 DCM 개량체의 개량효과를 개량형식에 따라 정량적으로 비교하기 위하여 일련의 실내모형 실험을 수행하였다. 즉, 무보강 및 3종류의 DCM 개량체 형식에 대한 상재하중 재하에 따른 지반 거동을 재현하고, 지반의 침하량 및 측방변위량을 분석함으로써 DCM 개량형식에 따른 연약지반의 거동을 평가하였다. 먼저, 모형지반에 대한 성토하중 재하시험 결과 무보강의 경우에는 작은 하중 증가에도 침하가 급격히 발생한 반면에, DCM 개량체가 적용된 경우에는 상대적으로 적은 침하가 발생하였다. 그리고 상재하중 증가에 따른 지반의 측방유동 거동을 분석한 결과, 무보강의 경우에는 작은 하중 증가에도 불구하고 측방변위가 크게 발생되었다. 그러나 DCM 개량체가 적용된 경우에는 상대적으로 적은 측방유동이 발생되었으며, 동일한 하중조건에 대한 측방유동 발생량의 크기는 말뚝식, 벽식, 격자식의 순으로 나타남을 확인하였다. 따라서 격자식 DCM 개량체가 적용된 경우가 측방유동에 대하여 우수한 지반개량효과를 나타낸 것으로 평가되었다.

• 한국지반공학회:학술대회논문집
• /
• 한국지반공학회 2005년도 지반공학 공동 학술발표회
• /
• pp.425-428
• /
• 2005

To resolve land demand by the development of various industries and the cityward tendency of population, the construction of ultra-soft ground that is unused in the past has been progressing with activity. The ultra-soft ground has very small shear strength and large deformation, so leads to many problems in ground improvement in construction. In order to dispose of these problems, it is necessary to develope the chemical materials that can be applied to the surface stabilization of ultra-soft ground. In this study, the new ground treatment that is using cement and SCS is compared, analyzed with existing ground treatment. In addition, through the laboratory tests that check the characteristic of congealment and strength, the application of SCS in field is affirmed.

• 한국지반공학회:학술대회논문집
• /
• 한국지반공학회 2009년도 세계 도시지반공학 심포지엄
• /
• pp.1158-1163
• /
• 2009

In this study, PSD system to improve the soft ground was developed by using a horizontal drainage pipe. PSD system is direct drain method for the disappearance of excess pore-water pressure which is caused by fill on soft ground. To conduct the field test construction in order to evaluate application of the PSD system. To estimate the behavior characteristics on settlement in which constructed by PSD system and compared the behavior characteristics with the conventional soft ground improvement method result.

• 한국지반공학회:학술대회논문집
• /
• 한국지반공학회 2000년도 가을 학술발표회 논문집
• /
• pp.41-48
• /
• 2000

Most land development projects and large scale civil works require a great amount of sand. And sand is also the most favorable material for soft ground improvement. The demand for sand is soaring rapidly due to increased number of projects regardless of its limited supply. Therefore, it is not difficult to predict that sand may become depleted and no longer be available as ground improvement material in the near future. Against this backdrop, developing an inexpensive sand-substitution material with an efficient accessibility will be necessary and urgently called for. So quick lime could be recommended as the substitutional material for sand. Quick lime is now preferred by forward developed nations. If Korea is able to take advantage of its abundant supply, economical efficiency could be achieved through massive production as well as being able to take advantage of utilization of natural resources. In this respect the purpose of this paper was to estimate improvement effect of soft ground though in-situ construction of quick lime pile. In-situ construction was peformed in road construction site of soft clay and in this study quick lime from Dan-yang that was estimated prominently in aspect of engineering characteristics was used. Quick lime piles were installed by 1.5m, 2.0m, 3.0m spacing to confirm improvement effect according to spacing and installed piles are 0.4m in diameter, up to 5m in length and the density of quick piles installed is 1.4 t/㎥. Vibrating wire pore water pressure cell was installed to confirm consolidation characteristics in surrounding of quick lime piles and both laboratory test and field test were carried out to confirm strength increase. In conclusion, soft ground improvement by quick lime piles was confirmed.

• 한국지반신소재학회논문집
• /
• 제17권2호
• /
• pp.1-7
• /
• 2018

해안지대나 습지와 같은 연약지반에 도로나 철도 건설이 빈번해지면서 이를 위한 연약지반 개량 사례가 증가하고 있다. 일반적으로 연약지반 개량시 작업조건만을 고려하거나 경제성만을 고려한 공법은 다수 존재하나 작업조건과 경제성을 함께 고려할 경우 적용 가능한 공법은 제한적이다. 이러한 경우 표층부와 심층부를 병용하여 개량하는 공법이 적용되어지는데, 이에 대한 기초적인 연구가 부족한 현실이다. 따라서, 본 연구에서는 연약지반에서 표층부 개량과 심층부 개량을 병용하는 경우에 대해 모형시험을 수행하여 지오그리드 보강 효과를 확인하고자 하였으며, 이때 표층부의 두께, 심층부 개량체의 직경 및 길이가 지오그리드 보강 효과에 미치는 영향을 파악하고자 하였다. 그 결과 표층부의 두께가 심층부의 직경보다 보강효과가 크다는 것을 확인하였고, 또한 표층부를 지오그리드로 보강한 경우 표층부의 강도가 증진되어 침하량이 저감됨을 확인하였다.

• 한국지반공학회논문집
• /
• 제18권5호
• /
• pp.43-54
• /
• 2002

연약지반에 구조물을 시공하는 경우가 빈번해짐에 따라 연약지반 개량의 필요성이 증대하고 있다. Granular pile 공법은 연약한 점성토 지반이나 느슨한 사질토 지반의 개량에 사용되는 연약지반처리공법이다. 국내에서는 모래를 이용한 SCP공법은 종종 사용해 왔지만 쇄석을 이용한 Granular pile은 외국에 비해 그 사용실적이 미비한 실정이다. 그러나 모래자원의 고갈에 따른 환경적, 경제적 인 문제 때문에 모래 대신 이용할 수 있는 대체재의 필요성이 절실해지고 있다. 본 연구에서는 Granular pile 공법에 의해 개량된 연약한 점성토 지반의 거동 특성을 파악하기 위하여 모형토조를 이용한 하중재하 및 압밀시험을 실시하였다. 또한, Pile 재료로서 모래뿐만 아니라 쇄석을 이용한 실내모형시험으로 각각의 재료에 따른 지지력 특성 및 침하 특성, 배수 특성 등의 공학적 특성을 비교 평가하여 모래의 대체재로서 쇄석의 활용가능성을 검토하였다. 시험결과, 쇄석은 모래 재료에 비해 지지력증대와 침하저감효과가 크고, 유사한 간극수압특성을 보여 모래의 대체재료로서 쇄석의 활용이 가능하다고 판단된다.

• 한국지반공학회:학술대회논문집
• /
• 한국지반공학회 2009년도 춘계 학술발표회
• /
• pp.743-749
• /
• 2009

In this study, the field test for suction drain method which does not require a surcharge load and a sealing sheet was performed at west seashore's site constructed by the dredged and reclaimed clay. The improvements of soft ground by suction drain method was analyzed by the results of real-time field measurement, SPT(Standard Penetration Test) and laboratory tests. The results indicated that the soft ground improvement is effective the vertical drain method used with vacuum pressure rather than surcharge load with considering settlements, dissipation of pore water pressure and shear strength.