• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2021년도 봄 학술논문 발표대회
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• pp.14-15
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• 2021

Recently, the size of tiles used for bathroom walls in apartment houses is gradually increasing in size. The problem is that when these large-sized tiles are attached by the sticking method, due to the nature of the method, there is a concern about the stability of the attachment to the part (pupil) where the tile and the adhesive are not attached. The problem is serious as it leads to lawsuits in the outbreak court. In addition, it is urgent to verify the adhesion stability of the sticking method because secondary damage occurs due to a safety accident caused by the falling of the tile. Ministry of Land, Infrastructure and Transport [Investigation of defects in apartment houses, calculation of repair cost and defect determination criteria] ① The tile adhesion strength is 0.39N/mm² or more and ② It is specified to fill 80% or more of the base area of the tile backside, but this is currently trendy. It is considered that large-sized tiles need to be verified from multiple angles, and as part of that, we intend to verify the adhesion stability according to the area to be attached to large-sized tiles.

• 방사성폐기물학회지
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• 제21권3호
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• pp.411-417
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• 2023

During the operation of a nuclear power plant (NPP), the generation of radioactive waste, including dry active waste (DAW), concentrates, spent resin, and filters, mandates the implementation of appropriate disposal methods to adhere to Korea's waste acceptance criteria (WAC). In this context, this study investigates the potential use of polymer concrete (PC) as a high-integrity container (HIC) material for solidifying and packaging these waste materials. PC is a versatile composite material comprising binding polymers, aggregates, and additives, known for its exceptional strength and chemical stability. A comprehensive analysis of PC's long-term integrity was conducted in this study. First, its compressive strength, which is crucial for ensuring the structural stability of HICs over extended periods, was evaluated. Subsequently, the resilience of PC was tested under various stress conditions, including biological, radiological, thermal, and chemical stressors. The findings of this study indicate that PC exhibits remarkable long-term properties, demonstrating exceptional stability even when subjected to diverse stressors. The results therefore underscore the potential viability of PC as a reliable material for constructing high-integrity containers, thus contributing to the safe and sustainable management of radioactive waste in NPPs.

• Structural Engineering and Mechanics
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• 제32권3호
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• pp.429-445
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• 2009

Thermal stability of quasi-isotropic composite and polymeric structures is considered one of the most important criteria in predicting life span of building structures. The outdoor applications of these structures have raised some legitimate concerns about their durability including moisture resistance and thermal stability. Exposure of such quasi-isotropic composite/polymeric structures to various and severe climatic conditions such as heat flux and frigid climate would change the material behavior and thermal viability and may lead to the degradation of material properties and building durability. This paper presents an analytical model for the generalized problem. This model accommodates the non-linearity and the non-homogeneity of the internal heat generated within the structure and the changes, modification to the material constants, and the structural size. The paper also investigates the effect of the incorporation of the temperature and/or material constant sensitive internal heat generation with four encountered climatic conditions on thermal stability of infinite cylindrical quasi-isotropic composite/polymeric structures. This can eventually result in the failure of such structures. Detailed critical analyses for four case studies which consider the population of the internal heat generation, cylindrical size, material constants, and four different climatic conditions are carried out. For each case of the proposed boundary conditions, the critical thermal stability parameter is determined. The results of this paper indicate that the thermal stability parameter is critically dependent on the cylinder size, material constants/selection, the convective heat transfer coefficient, subjected heat flux and other constants accrued from the structure environment.

• 한국지반신소재학회논문집
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• 제12권1호
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• pp.101-107
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• 2013

최근 들어 토목 구조물에도 친환경성과 경제성이 강조되고 있으며 콘크리트 블록대신 soilbag을 전면벽으로 이용하는 절토사면 보강공법이 활용되고 있다. 그러나 친환경적이고 경제적인 재료라 하더라도 안정성이 보장되지 않으면 구조물로써의 가치를 지닐 수 없다. Soilbag 옹벽의 안전성 검토를 위해 기존의 옹벽 설계프로그램인 MSEW를 사용하여 연결부에서의 인발저항, 파단, 인장응력과 내적, 외적 안전율을 산정하고 블록식 보강토 옹벽의 안전율 산정결과와 비교하였다. 연결부의 안전성을 평가할 수 있는 연결강도 감소계수를 차등 적용시켜 연결강도가 감소함에 따라 옹벽의 안전율을 검토하였고 soilbag 보강토 옹벽에서는 soilbag과 지오그리드 보강재의 연결재가 이동이 가능하기 때문에 전면구배의 변경이 자유로우므로 soilbag의 구배에 따른 안전율 변화도 확인하였다. 해석결과로부터 soilbag을 이용한 보강토 옹벽의 연결부 강도에 대한 안전율 및 내적, 외적안정에 대한 안전율을 비교 검토한 결과 전 영역에서 기준 안전율 이상임을 나타내었다.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2008년도 추계 학술발표회
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• pp.569-580
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• 2008

If slope height was more than 20 meters, we conducted an analysis of stereographic projection and limit equilibrium at this slope. We proposed reduction of slope face angle and reinforcement of rock bolt depending on analysis. Blasting design : Standard pattern based on result of local test blasting was made for blasting design. Vibration criterion was set for less than 3.0mm/s because of outworn buildings and inhabitants opinions. Production blasting and Controlled blasting has been done as Construction standard pattern. After Vibration Monitoring has been done, so that we can control of complement. "Bidding Document" and AASHTO 2001 "A Policy on Geometric Design of Highways and Streets" were so for design criteria of earthwork but they were different actual design criteria and left something to be desired in Afghanistan. Therefore, although "Bidding Document" and "AASHTO 2001" were basic design criteria, domestic design criteria was reflected in this design criteria for complement by discussion with supervisor. Drainage design : For stability ratio, ditch of arch block and stonework was designed by rainfall data for the 13 years and discussion with supervisor. Pavement was designed as flexible pavement. Because these days in Afghanistan postwar repair works, especially urgent repairing of roads and newly making of roads, are very highly in progress, I think that Afghanistan is the region about which our construction technical experts should have great concerns.

• 한국지반공학회논문집
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• 제38권2호
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• pp.15-27
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• 2022

암반 그라우팅은 시설물 지반의 안정성을 향상시키는 보강 및 재해방지 대책으로서의 적용성이 날로 증가하고 있으나, 현장에서의 그라우팅은 대부분 경험에 의존하는 바 가이드라인으로 사용할 수 있는 주요 계획인자에 대한 최소 기준값이 필요한 실정이다. 본 연구에서는 암반 그라우팅 계획에 있어 중요한 인자인 주입조건(물-시멘트비, 주입압, 단위 시멘트 주입량)과 그라우팅 효과(변형계수와 투수성)에 대한 기준값을 제시하였다. 제시된 기준값들은 국내외 수압파쇄시험 및 암반 투수시험 자료, 국내외 17개 현장의 그라우팅 시험시공 자료, 그리고 국내외 기준 및 연구를 분석한 결과이다. 또한 그라우팅 효과를 제고하기 위한 안정한 주입재의 조건에 부합하도록 국내의 높은 물-시멘트비는 조정되어야 하며, 조정된 물-시멘트비 적용에 따른 기준값 조정방안도 살펴보았다. 본 연구의 결과 역시 경험의존적인 측면이 있지만, 현재 기준 보다 합리적인 그라우팅 계획의 기준을 제시를 위한 향후 세부연구의 기초자료로 활용할 수 있을 것이다.

• 산업공학
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• 제25권1호
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• pp.96-105
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• 2012

Recently, the interoperability has become more important to enhance the net-centric capabilities of the warfighter. DITA (Defense Information Technical stAndard) is the set of IT standards for improving interoperability, scalability, effectiveness, and efficiency. In this paper, we analyzed the standardizing process to derive the selection criteria and structurized the derived selection criteria using the KJ (Kawakita Jiro) method. Finally, we developed an evaluation model for selecting a standard for DITA using AHP (Analytic Hierarchy Process). As a result, we present eight selection criteria (maintainability, trend, stability, portability, effect of other standard, constraint of the network, and applicability to the systems). We also applied some examples that several IT standards to our selection model for validating the model. We expect our model to help to decide objectively whether the new standard can be listed in DITA.

• 한국항공우주학회지
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• 제41권7호
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• pp.569-576
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• 2013

군용항공기 산업의 비약적인 발전으로 정부의 군용항공기 감항인증은 점차적으로 중요한 역할을 차지하고 있다. 감항인증은 모든 항공기가 전 수명주기 동안 운용범위 내에서 비행안전에 적합하도록 항공기 개발에 필수적으로 요구되는 절차이다. 감항인증의 도입은 단일 수요자의 요구도에 부합되게 개발 해왔던 기존의 개발 사업특성에서 다수의 수요자의 공통의 요구도를 맞춘 개발 패러다임의 변화로 이끌어 가고 있다. 본 논문에서는 전투기급 항공기의 비행제어법칙의 감항인증 기준 설정에 대한 상세 연구와 감항인증 기술기준에 대한 입증 분석을 결과로 제시하였다.

• 대한토목학회논문집
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• 제33권4호
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• pp.1471-1478
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• 2013

본 논문에서는 이중보온관의 발파진동 관리기준 제시를 위하여 이격거리와 매설심도를 변수로하여 수치해석을 수행하였다. 수치해석 적용 발파하중 모델은 현장시험 결과와의 비교를 통하여 검증하였다. 수치해석 결과, 이중보온관은 진동속도 4.0cm/sec 이상에서 발생 유효응력이 내관의 허용응력을 초과하거나 근접하는 것으로 나타났으며, 4.0cm/sec 이하에서 안정성이 확보되는 것으로 평가되었다. 따라서, 이중보온관의 진동관리기준은 4.0cm/sec를 초과하지 않도록 관리하여야 할 것으로 판단된다.

• 기술발표회
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• 통권2006호
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• pp.86-100
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• 2006

The single drilled shaft foundation has been used in the other countries, but has not used in South Korea at all This foundation is very effective and economic method in South Korea which is easy to meet a good rock mass within 50m depth from the ground We have many experiences to construct 1.52 5m drilled shaft foundations and ability to construct 30m drilled shaft foundation without special efforts The soil behavior is nonlinear, but it can be proposed in linear in practical purpose on bridges. The elastic modulus of soil can be rationally obtained by the method of Road Bridge Design Manual in South Korea using the Schmertmann(1970)'s proposal, and the elastic modulus of rock can be obtained by the field test. In seismic design the column and drilled shaft must be restricted to the elastic design because the behavior of this foundation is flexible and the arrangement of the rebars makes the various defect In this paper the design criteria is compared with FHWA design criteria, and the design criteria is proposed in consistent with Road Bridge Design Manual in South Korea. The single drilled shaft foundation of a test bridge was constructed in the Iksan-Jangsoo highway, and we checked its stability, workability and economy