• Journal of the Korean Geotechnical Society
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• v.17 no.5
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• pp.181-196
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• 2001

지하구조물에 있어서 누수사고의 빈번한 발생 및 상습화 경향에도 불구하고 현재 국내에서 사용되고 있는 누수보수방법은 누수유형에 관계없이 일괄적으로 동일한 처리방식으로 보수하는 상황으로서 지하구조물 누수에 대하여 누수 유형별로 보수방법을 달리하는 적극적인 해결방안의 모색이 필요하다. 따라서, 본 연구에서는 지하구조물의 누수보수에 있어서 방수 그라우트재의 공학적 특성을 파악하고 현장상황에 적합한 방수그라우팅 기법을 수립하여 누수유형별로 적용한 사례를 중심으로 적용성을 고찰하였다. 방수그라우팅 적용사례를 분석한 결과 지하구조물의 누수방지를 위하여 누수상황 및 누수유형에 따라 주입재의 배합비를 적절히 변화시켜 주입재와 현장상황에 적합한 방수그라우팅 기법을 병행 적용하는 것이 확실한 방수효과를 얻을 수 있으며, 주입목표구간에 대해 단계적으로 수회로 나누어 순차적인 그라우팅과 가능한 한 저압, 소량, 장시간에 걸쳐 주입하는 것이 방수그라우팅 효과를 증대시킬 수 있는 것으로 판단된다. 또한, 현장 적용결과로부터 기존 방수이론의 영향요소에 추가하여 물시멘트비, 주입재의 입경, 주입시간 및 주입량, 혼화재 사용여부, 주입차수 등에 대한 다양한 영향요소의 검토가 필요한 것으로 판단된다.

• The Journal of Engineering Geology
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• v.9 no.3
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• pp.187-206
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• 1999

A computer program to numerically predict the permeability tensor of fractured rocks is developed using information on discontinuities which Borehole Televiewer and Borehole Image Processing System (BIPS) provide. It uses orientation and thickness of a large number of discontinuities as input data, and calculates relative values of the 9 elements consisting of the permeability tensor by the formulation based on the EPM model, which regards a fractured rock as a homogeneous, anisotropic porous medium. In order to assess feasibility of the program on field sites, the numerically calculated tensor was obtained using BIPS logs and compared to the results of pumping test conducted in the boreholes of the study area. The degree of horizontal anisotropy and the direction of maximum horizontal permeability are 2.8 and $N77^{\circ}CE$, respectively, determined from the pumping test data, while 3.0 and $N63^{\circ}CE$ from the numerical analysis by the developed program. Disagreement between two analyses, especially for the principal direction of anisotropy, seems to be caused by problems in analyzing the pumping test data, in applicability of the EPM model and the cubic law, and in simplified relationship between the crack size and aperture. Aside from these problems, consideration of hydraulic parameters characterizing roughness of cracks and infilling materials seems to be required to improve feasibility of the proposed program. Three-dimensional assessment of its feasibility on field sites can be accomplished by conducting a series of cross-hole packer tests consisting of an injecting well and a monitoring well at close distance.

• Journal of the Korean Geotechnical Society
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• v.16 no.5
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• pp.117-127
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• 2000

터널 시공과 굴착과정에서 파쇄대, 절리, 연약대, 균열 등 암반에서의 불연속면은 중요한 역할을 한다. 본 연구에서는 지반 고유의 특징인 불확실성에 의한 터널 설계와 시공 과정에서 겪는 많은 시행오차를 최소화하기 위해서 국내의 터널 붕락 현장의 지반조사 자료를 분석하여 터널 붕락 유형 및 규모를 제시할수 있는 Geo-predict 시스템을 개발하였다. Geo-predict 시스템은 총 104개 터널 붕괴/붕락자료(국외84개, 국내20개)를 분석한 자료를 테이터베이스로 인공신경망 학습을 토해서 터널 붕괴 형태와 규모를 추론하는 시스템이다. 본 논문에서는 Geo-predict의 개발과정 및 구성.기능을 소개하였으며 104개 터널 현장 자료를 지반조건별로 분석하고 이를 데이터베이스화하여 인공신경함을 이용한 추론 시스탬을 구축하고, 2개 고속전철 터널현장과 1개 지하철 시공현장에 적용성 평가를 실시하여, 터널의 붕락 가능 및 붕락 규모를 추론하였다.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.35 no.2
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• pp.361-375
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• 2015

An energy pile is one of the novel ground heat exchangers (GHEX's) that is a economical alternative to the conventional closed-loop vertical GHEX. The combined system of both a structural foundation and a GHEX contains a heat exchange pipe inside the pile foundation and allows a working fluid circulating through the pipe, inducing heat exchange with the ground formation. In this paper, a group of energy piles equipped with parallel U-type (5, 8 and 10 pairs) heat exchange pipes was constructed in a test-bed by fabricating in large-diameter cast-in-place concrete piles. In addition, a closed-loop vertical GHEX with 30m depth was constructed nearby to conduct in-situ thermal response tests (TRTs) and to compare with the thermal performance of the cast-in-place energy piles. A series of thermal performance tests was carried out with application of an artificial cooling and heating load to evaluate the heat exchange rate of energy piles. The applicability of cast-in-place energy piles was evaluated by comparing the relative heat exchange efficiency and heat exchange rate with preceding studies. Finally, it is concluded that the cast-in-place energy piles constructed in the test-bed demonstrate effective and stable thermal performance compared with the other types of GHEX.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.10
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• pp.468-477
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• 2019

This study analyzed the major contents and results of revision through an analysis of the specifications and the field survey to revise the construction cost calculation criteria. The result of the survey found that the background processing difficulty was reduced due to an improvement of the quality level of the field floor, and the enhancement of the material's function brought a decrease in construction time and the application of various construction methods. In addition, the application of combined waterproofing methods using more than one material was increasing and the productivity differed according to the site and location. Based on these results, waterproof items were subdivided and applied to the composite construction method, and the input items were differentiated according to the material and construction method. The adequacy of the construction calculation criteria was ensured by presenting the criteria classified according to the construction area, and deleting the items that are not applicable and amending them to make them suitable for the specifications by reflecting the actual conditions of the construction on the site.

• Proceedings of the Korean Institute Of Construction Engineering and Management
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• 2007.11a
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• pp.925-928
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• 2007

As the field report data does not normalize, ordering organization requires different form every time and field reporters make out form as random, data and report to the ordering organization by different medium such as FAX, e-mail, paper document. Therefore, Field reporters must set and make out same information in required pattern. And ordering organization is being responsible for side works of totalizing and processing the reported data. This research suggests the electronic document unification about monthly construction progress report and construction present condition report system. In addition, it suggests electronically processing function that can handle field report business to unifying electronic documents. As using the result of this research, it will improve the work efficiency and simplify in report business.

• Journal of the Korean Recycled Construction Resources Institute
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• v.3 no.1
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• pp.72-83
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• 2015

Underground transmission lines always generate heat and transmit heat through surrounding backfill materials. Therefore, in the design of power lines it becomes a very crucial factor to transfer heat effectively into the neighbouring soils. In this study, in order to enhance field applicability of recycled aggregates for backfill material of transmission lines, quality criteria and construction criteria were proposed, and thermal stability of power lines through field demonstration tests were analyzed. In the field tests, two types of recycled aggregates and sand which is currently used for backfilling were compared in terms of thermal behaviour. Test results showed that recycled aggregates represented similar trends with sand in temperature and moisture content corresponding to time lapse and distance from the heat source. Consequently, recycled aggregates can be utilized for backfill materials of underground transmission lines as a substitute material of sands.

• Journal of Korean Tunnelling and Underground Space Association
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• v.15 no.3
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• pp.321-331
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• 2013

This paper describes the evaluation of shield TBM disc cutter penetration depth in practice. In this study the disc cutter penetration depth used to design the excavation speed of tunnel is reviewed. The characteristics of ground encountered in the investigation site are analysed and evaluated. The shield TBM used in the field is reviewed to verify the applicability of machine in the site. The thrust and torque capacities of each TBM disc cutter are also evaluated. Based on the field data, the excavation volume and speed are re-analysed to evaluate the disc cutter penetration depth used in the design stage. It is clearly found that the design value of disc cutter penetration depth needs to modify when estimation of the TBM capacities in very hard rock formation ($S_c$ >150 MPa).

• Journal of Digital Convergence
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• v.16 no.11
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• pp.633-638
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• 2018

The number of individuals with spinal cord injuries in the most countries is rising each year. However, it is reported that most of them have sexual problem, however lack of research on deal with the issues related to sex identity and maladjustment in rehabilitation counseling setting. The purpose of this article: (a) to possess an adequate knowledge of the sexual problems facing individuals with spinal cord injuries; (b) to review past research on sexuality counseling with people who have spinal cord injuries; and (c) to present for some strategies for people with spinal cord injuries in order to sexuality adjustment, through Cognitive Behavior Therapy. Some suggestions are presented.

• Journal of Korean Society of Disaster and Security
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• v.6 no.1
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• pp.35-45
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• 2013

In recent years, increasing damage due to landslides. So the government is to create a geotechnical hazard map. This study was to evaluate the applicability of the geotechnical hazard map by using 4 years of landslide cases in Seoul and Busan. And the in-situ aseessment has been carried out in test-bad area with specialists. Study has shown dangerous grade in geotechnical hazard map is more dangerous than the actual. Thus we can utilize geotechnical hazrd map in the purpose of the geotechnical hazard preliminary assessment. However, the in-site inspection and evaluation is required for in order to select the hazard area.