• 한국지반공학회:학술대회논문집
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• 한국지반공학회 1992년도 가을학술발표회 논문집
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• pp.11-26
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• 1992

An attempt has been made to summarize some of the unique geotechnical problems encountered during construction of a few large man-made islands recently completed off the coast of Osaka Bay, Japan. Large settlements appear to be the most serious problem both during and after construction. Settlements due to consolidation of a thick layer of soft alluvial clay that constitutes seabed seem to virtually cease within a relatively short period of time when vertical drains are installed adequately prior to fill placement. Settlements due to compression of underlying thick diluvial deposits consisting of layers of stiff clays interbedded with coarse-grained soils, however, continue over a prolonged period of time and call for special provisions for structures built on the artificial islands to cope with relatively large future settlements. Although accurate settlement prediction is not possible, it is both technically and economically feasible, nevertheless, to construct large-scale islands. Partjcularly attractive and promising is creation of sizable new areas for various purposes, immediately adjacent to highly-developed, densely-populated cities situated along the coast such as those around Osaka Bay.

• 농업과학연구
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• 제29권2호
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• pp.53-66
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• 2002

본 연구는 연약지반상에 축조되는 농업용 저수지의 압밀거동을 현장계측결과를 기초로 기존의 예측방법등과 비교분석하고, 시공중 또는 완공후에 측방유동등으로 인하여 국부적인 전단파괴 가능성을 현장계측치로부터 정량적으로 파악하여 비교분석한 결과 다음과 같은 결론을 얻었다. 1. 최종 예상침하량으로 추정한 압밀도는 Terzaghi 방법에서는 작게 추정되었고, 편차가 크게 나타나서 오차범위가 작은 Asaoka와 Hyperbolic 방법을 기준으로 압밀도를 적용하는 것이 합리적이라고 판단된다. 2. 성토에 의한 점증재하시 과잉간극수압의 소산은 성토시공중의 소산과 최대간극수압 이후의 소산이 합성되어 발생하는 복합적인 거동을 나타냈다. 또한 압밀초기에는 침하량으로 압밀도를 예측하는 것보다 계측자료가 충분한 과잉간극 수압을 이용하여 압밀도를 예측하는 것이 신뢰성이 클 것으로 판단된다. 3. 성토완료후 초기에는 시공중 소산된 과잉간극수압 ($U_d$)을 이용한 압밀도가 최대과잉간극수압을 이용한 압밀도 ($U_p$)보다 12~27% 정도 더 크게 나타났고, 침하량으로 추정된 압밀도에 근접하므로 소산된 과잉간극수압에 의하여 압밀도를 추정하는 것이 합리적이라 판단된다. 4. $U_d$와 $U_p$의 관계식은 주계측 단면에서는 $U_d=(1.3{\sim}3.6)U_p$, 부계측 단면에서는 $U_d=(1.2{\sim}1.9)U_p$로 소산된 과잉간극수압으로 추정된 압밀도가 더 크게 나타났다. 또한 저수지 제체의 안정성을 한계평형법에 의해 분석한 결과 모든 조건에서 기준 안전율보다 커서 안정한 상태로 나타났다.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2006년도 춘계 학술발표회 논문집
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• pp.1046-1053
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• 2006

In the large scale recent reclaiming works performed within the wide spatial boundary, evaluation of long-term consolidation settlement and residual settlement of the whole construction area is sometimes made with the results of the limited ground investigation and measurement. Then the reliability of evaluation has limitations due to the spatial uncertainty. Additionally, in case of large scale deep excavation works such as urban subway construction, there are a lot of hazardous elements to threaten the safety of underground pipes or adjacent structures. Therefore it is necessary to introduce a damage prediction system of adjacent structures and others. For the more accurate analysis of monitoring information in the wide spatial boundary works and large scale urban deep excavations, it is necessary to perform statistical and spatial analysis considering the geographical spatial effect of ground and monitoring information in stead of using diagrammatization method based on a time-series data expression that is traditionally used. And also it is necessary that enormous ground information and measurement data, digital maps are accumulated in a database, and they are controlled in a integrating system. On the abovementioned point of view, we developed Geomonitor 2.0, an Internet based real time monitoring program with a new concept by adding GIS and geo-statistical analysis method to the existing real time integrated measurement system that is already developed and under useful use. The new program enables the spatial analysis and database of monitoring data and ground information, and helps the construction- related persons make a quick and accurate decision for the economical and safe construction.

• Geomechanics and Engineering
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• 제13권1호
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• pp.79-97
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• 2017

Natural clays exhibit features such as structural and anisotropy. In this work, a constitutive model that is able to replicate these two salient features of natural clays is presented. The proposed model is based on the classical S-CLAY1 model, where the anisotropy of the soil is captured through the initial inclination and rotation of the yield surface. To account for the structural of the soil, the compression curve of the reconstituted soil is taken as the reference. All parameters of the proposed constitutive model have clear physical meanings and can be conveniently determined from conventional triaxial tests. This proposed model has been used to simulate the behavior of soft soil in the undrained triaxial tests and the performance of Murro embankment in terms of settlement and horizontal displacements during embankment construction and consolidation stage. Results of numerical simulations using proposed model have been compared with the field measurement data. The comparisons show that the two features significantly influence the prediction results.

• Current Research on Agriculture and Life Sciences
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• 제4권
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• pp.87-94
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• 1986

본(本) 연구(硏究)에서는 주요(主要) 항만(港灣)에서 채취(採取)한 해성점토(海性粘土)에 대(對)하여 각종(各種) 공학력(工學力) 성질(性質)들을 측정(測定)하여 이들의 상호관계(相互關係)를 분석(分析) 고찰(考察)하였는바 그 결과(結果)를 요약(要約)하면 다음과 같다. 1. 본(本) 시험지구(試驗地區)의 흙은 대구분(大部分)이 CH, CL, ML로 구성(構成)되어 있으며 초기압밀(初期壓密)이 진행중(進行中)인 것으로 사료(思料)된다. 2. 압축지수(壓縮指數)와 액성한계(液性限界)의 관계식(關係式)은 다음과 같다. CH : $C_c=0.0137$ (LL-22.6) CL : $C_c=0.0123$ (LL-14.64) 3. 압축지수(壓縮指數)와 초기간극비(初期間隙比)의 관계(關係)는 소성(塑性)이 높은 흙 일수록 기울기가 완만하였으며 그 관계식(關係式)은 다음과 같다. CH : $C_c=0.431$ ($e_o-0.504$) CH : $C_c=0.471$ ( $e_o-0.235$) ML : $C_c=0.641$ ($e_o-0.393$) 4. 압축지수(壓縮指數)와 자연함수비(自然含水比)의 관계식(關係式)은 다음과 같다. CH : $C_c=0.0133$ ($W_n-28.27$) CL : $C_c=0.0225$ ($W_n-23.56$) ML : $C_c=0.0106$ ($W_n-16.42$) 5. 초기간극비(初期間隙比) 및 자연함수비(自然含水比)와 압축지수(壓縮指數)의 관계(關係)는 높은 정(正)의 상관(相關)으로 그 관계식(關係式)은 다음과 같다. CH : $C_c=0.301$ ($e_o+0.017W_n-1.05$) CL : $C_c=0.141$ ($e_o+0.0567W_n-1.054$) ML : $C_c=0.421$ ($e_o+0.0214W_n-1.121$) 6. 초기간극비(初期間隙比) 및 액성한계(液性限界)와 압축지수(壓縮指數)의 관계식(關係式)은 다음과 같다. CH : $C_c=0.36$ ($e_o+0.08LL-0.819$) CL : $C_c=0.269$ ($e_o+0.026LL-0.929$) 7. 해성점토(海性粘土)의 점착력(粘着力)은 심도(深度)와 상관성(相關性)이 없으며 일축압축강도(一軸壓縮强度)와의 관계식(關係式)은 다음과 같다. CH : qu=1.896C+0.0107 CL : qu=1.849C+0.04.