• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2006년도 춘계 학술발표회 논문집
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• pp.348-351
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• 2006

This paper presents preliminary laboratory investigations on the electrokinetic (EK) remediation coupled with permeable reactive barrier (PRB) system. Atomizing slag was adopted as a PRB reactive material for remediation of groundwater contaminated with inorganic and/or organic substances. A series of laboratory experiments were performed with variable conditions such as (i) type of contaminant, (ii) applied electric field strength, (iii) processing time, and (iv) the application of PRB system. From the preliminary investigations, the coupled technology of EK with PRB system would be effective to remediate contaminated grounds without the extraction of pollutants from subsurface due to the reactions between the reactive materials and contaminants.

• Structural Monitoring and Maintenance
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• 제1권2호
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• pp.231-247
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• 2014

This paper focuses on the dynamic behaviour of Mirandola City Hall (a XV century Renaissance Palace) that was severely damaged during May 2012 Emilia earthquake in Northern Italy. Experimental investigations have been carried out on this monumental building. Firstly, detailed investigations have been carried out to identify the identification of the geometry of the main constructional parts as well as the mechanical features of the constituting materials of the palace. Then, Ambient Vibration Tests (AVT) have been applied, for the detection of the main dynamic features. Three output-only identification methods have been compared: (i) the Frequency Domain Decomposition, (ii) the Random Decrement (RD) and the (iii) Eigensystem Realization Algorithm (ERA). The modal parameters of the Palace were difficult to be identified due to the severe structural damage; however the two bending modes in the perpendicular directions were identified. The comparison of the three experimental techniques showed a good agreement confirming the reliability of the three identification methods.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 1993년도 지하공간 건설기술에 관한 서울 심포지움 논문집
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• pp.235-247
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• 1993

The 62 m span Olympic lee Hockey cavern in Gjovik, Norway, is located in jointed gneiss of average RaD = 70% and has a rock cover of only 25 to 50m, thus posing challenging design p problems. The investigations prior to construction included two types of stress measurements, cross-hole seismic tomography, special coe logging, Q-system classification and numerical modelling with UDEC-BB. Predicted maximum deformations were 4 to 8 mm; surprisingly small due to the high horizontal stresses recorded. Extensometer (MPBX) installations from the surface prior to construction, precision surface levelling and MPBX installed from inside the cavern give a combined measure of maximum deformations in the range 7 to 8 mm with the 62 m span fully e excavated, and three adjacent caverns for the Postal Services also completed.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2003년도 봄 학술발표회 논문집
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• pp.217-222
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• 2003

This study was carried out to investigate the geotechnical characteristics and field application of soil mixed with waste lime. Waste lime used in this study is producted as a by-product in the manufacturing process of making Na$_2$CO$_3$from local chemical factory in Incheon. Currently about 320 milton tons of waste lime are accumulated and annually 100,000 tons are producted. In this study, feasible use of waste lime mixed with granited whathered soil, clay, crushed rock was invesigated through laboratory tests including specific gravity test, sieve analysis, hydrometer analysis, compaction test, CBR test. Field investigations were conducted on the road construction site in Incheon.

• Geomechanics and Engineering
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• 제25권4호
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• pp.295-302
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• 2021

Cross-borehole electrical resistivity tomography (ERT) is an effective groundwater detection tool in geophysical investigations. In this paper, an artificial water injection test was conducted on a small clay sample, where the high-resolution cross-borehole ERT was used to investigate the moisture migration law over time. The moisture migration path can be two-dimensionally imaged based on the relationship between resistivity and saturation. The hydraulic conductivity was estimated, and the magnitude ranged from 10^-11 m/s to 10^-9 m/s according to the comparison between the simulation flow and the saturation distribution inferred from ERT. The results indicate that cross-borehole ERT could help determine the resistivity distribution of small size clay samples. Finally, the cross-borehole ERT technique has been applied to investigate the self-sealing characteristics of clay.

• 한국지반공학회논문집
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• 제19권2호
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• pp.57-64
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• 2003

지진하중조건에서 포화된 모래의 액상화 가능성은 심도 있는 연구가 진행되어 왔다. 이러한 연구에서 대표적인것은 실험실에서 반복삼축압축시험에 의하여 모래의 반복강도를 결정하는 것이다. 본 연구는 재성형된 포화 균등모래의 액상화 특성에 있어서 시편의 성형방법에 따른 영향을 검증하기 위하여 수행되었다. 건조시료의 공기중낙하다짐, 습윤층다짐, 습윤진동층다짐 등 3가지 방법에 의하여 동일한 밀도로 다짐된 포화된 균등한 모래에 대하여 삼축압축시험이 수행되었다. 같은 밀도에서 다른 방법에 의하여 성형된 포화된 균등한 모래의 액상화 저항특성인 반복응력비는 크게 다른 것으로 확인되었다.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2006년도 춘계 학술발표회 논문집
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• pp.445-454
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• 2006

Myungji Housing Complex is located in the Nakdong River plain in which the Busan soft clays are developed. It has thick soft soil laver of about GL(-)50m including loose sandy layers, upper and lower clayey layers. The clayey layers have been being consolidated since the land reclamation was completed to build the place for Housing Complex(Apartment) in 1997. Therefore, as one of a series of advance preparations of this project, study was carried on the geotechnical characteristics under the foundation The first part of this paper represents a brief geological history. Then, geotechnical characteristics of clay was analyzed in the classical developments in soft clay. They were based on the geotechnical data obtained by site investigations performed from 1992 to 2005. Finally, we evaluated the average degree of consolidation at this point in time and the residual settlements of upper clayey layer using dissipation and oedometer tests for this project

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2004년도 춘계학술발표회
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• pp.897-903
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• 2004

Waste lime used in this study is producted as a by-product in the manufacturing process of making $Na_2CO_3$ from local chemical factory in Incheon. Currently about 320 millon tons of waste lime are accumulated and annually 100,000 tons are producted. Reuse of waste lime mixed with soil for banking and backfill materia in civil works was analysed in this study. This study was Carried out to investigate the geotechnical and environmental characteristics on field application. Field investigations were conducted on the road construction site in Incheon. This study presents the results of the engineering characteristics in field test and the leaching characteristic of waste lime in laboratory column tests. Countermeasure for reduction of environmental effects was suggested from the test results.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2001년도 봄 학술발표회 논문집
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• pp.89-96
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• 2001

A concrete lining of NATM tunnel is the final product of a process that involves planning and evaluation of user needs, geotechnical investigations, analysis of ground-lining interaction, construction, and observations and modifications during construction. The designer must consider the lining in context of the many function, construction, and geotechnical requirements. Also, the loss of supporting capacity of shotcrete lining due to poor rock qualities and shotcrete erosion must be considered. The values, shapes, and estimating methods of rock load and water pressure are very different with every designers. Estimating methods of rock loads used in the design of NATM tunnel concrete lining are investigated. Numerical analyses are done in various conditions. And the rock loads estimated from radial stress and plastic zone are compared respectively.

• Geomechanics and Engineering
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• 제8권5호
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• pp.727-739
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• 2015

Reclamation of closed dumping grounds is a potential solution to solve land scarce problems. Traditional geotechnical investigations of closed dumping grounds face some problems, such as the emission of hazardous liquids and gases, and the lack of ground information due to the discontinuity between two boreholes. Thus, noninvasive and continuous investigation methods are needed to supplement traditional geotechnical investigations. In this paper, two types of geophysical investigation methods, Seismic Analysis of Surface Waves (SASW) and 2D Resistivity, were carried out to study noninvasive and continuous site investigations for dumping grounds. The two geophysical methods are able to profile the distribution of physical properties of the fill and original materials, by which the extent of the dumping ground can be found and some anomalies in the subsurface can be located. Boreholes were used to assist in locating the dumping material-ground interfaces. The results show that dumping material-ground interfaces obtained from the two geophysical methods are roughly consistent. Moreover, attempt is made in the paper to use the geophysical methods to classify the types of dumping materials. The results show that the classification of dumping materials using the geophysical methods follows the results of the manual sorting of the dumping materials from a borehole.