• 한국구조물진단유지관리공학회 논문집
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• 제11권1호
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• pp.171-180
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• 2007

처짐, 응력 및 휨강도 한계상태에 대한 PSSC(prestressed steel and concrete)거더의 신뢰도해석을 수행한다. PSSC 거더는 시공비용과 형하공간의 확보 면에서 지간 40m이상인 교량에 적용하는데 커다란 장점을 가지고 있는 형식이다. 이 논문에서는 다양한 지간, 단면 및 설계 응력수준을 가지는 PSSC 거더를 설계하여 중앙점 처짐, 응력 및 단면 휨모멘트 해석을 수행하고, 각각에 대한 한계상태를 가정한 후, Monte-Carlo 시뮬레이션과 Rackwitz-Fiessler 방법을 이용하여 신뢰도지수를 구한다. 결과를 분석하면 PSSC 거더에 대한 처짐한계상태는 응력한계상태보다 적절하게 큰 신뢰도지수 값을 보이며, 휨강도에 대한 신뢰도지수가 매우 큼을 알 수 있다.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2008년도 추계학술대회 논문집
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• pp.386-389
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• 2008

Forming limit diagram is created by graphical illustration indicating major and minor strain. In order to provide the criterion for forming safety, FLC(forming limit curve) need to be fitted to the diagram. However, the standard method for the strain measurement and FLC plotting are not fixed yet, which results in inconvenience in digitalized analysis. In this study, new construction method for FLC was suggested in order to minimize operator dependency. For this purpose, major and minor strain were measured automatically and analyzed. Then, a second order equation is adopted to fit the FLC. Optimized by response surface method was performed to ensure particular characteristics of the FLC.

• 한국농공학회지
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• 제18권4호
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• pp.4251-4258
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• 1976

In the construction of earth dam, embankment and highway by filling, a compaction contributes to increasing the density of soil by applying pressure. The effect of compaction depends on various factors such as soil type, moisture content, gradation, consistency, and compaction energy. In this study, the correlations amone maximum dry density, moisture content, dry density, and moisture content are analyzed. Some results obtained in this study are summarizep as follows. 1. The maximum dry density sinoreases with increased of optimum moisture content and the correlations of them can be represented by; ${\gamma}$dmx=a-b(W0) 2. Maximum dry density and liquid limit show negative linear correlation and can be represented by; ${\gamma}$dmx=a-b(LL). 3. Optimum moisture content and liquid limit, plastic limit show positive linear correlation and can be represented by the following equation, W0=a+b(LL) W0=a+b(PL). 4. Liquid limit and plastic limit show positive linear correlation, and can be represented by the following equation, LL=a+b(PL).

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2002년도 봄 학술발표회 논문집
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• pp.643-650
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• 2002

The large planar failure has occurred in a rock cut slope of highway construction site in Boeun. This area is considered as unstable since the discontinuities whose orientations are similar to the orientation of the failure plane, are observed in many areas. Therefore, several analysis techniques such as SMR, stereographic analysis, limit equilibrium, numerical analysis, which are commonly used in rock slope stability analysis, are adopted in this area. In order to analyze the stress redistribution and nonlinear displacement caused by cut, which are not obtained in limit equilibrium method, the UDEC and shear strength reduction technique were used in this study Then the factors of safety evaluated by shear strength reduction technique and limit equilibrium were compared. In addition, the factor of safety under fully saturated slope condition was calculated and subsequently, the effect of the reinforcement was evaluated.

• 국제강구조저널
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• 제18권4호
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• pp.1098-1106
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• 2018

The object of this study is to clarify fatigue limit and fatigue crack growth characteristic of SBHS700 base metal which is 780 MPa class steel. This study carried out the fatigue tests of SBHS700 base metal containing different defect size, and the fatigue limit was compared with that of the conventional steel. Test results indicate that the fatigue limit increased with decrease initial defect size, and can be precisely evaluated by using ${\sqrt{area}}$ parameter model. This paper also presents that crack growth characteristic was almost the same as that of the conventional steel from the observation of striations by using Scanning electron microscope and length of beach marks.

• 한국지반공학회지:지반
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• 제11권2호
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• pp.99-106
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• 1995

기본적인 성질 평가와 많은 실내실험을 통해 우리나라에서 부산되는 석탄재는 이제 실용화 단계에 있지만, 가장 문제 제기가 되고 있는 부분은 환경적 특성 검토이다. 본 연구에서는 석탄재 발생량의 대부분을 차지하고 있는, 역학적 특성이 열악한 fly ash.를 대상으로 우리나라 환경기 준에 의하여 폐기물 분류를 분석 확인하구 매립 및 대규모 토공재 등 건설재료로 처리 또는 사용하였을 시 오염물질 배출허용기준에 의한 문제점이 있는가를 검토하기 위하여 회분식 용출시험에 의하여 수소이온농도 및 오염물질 함유량을 조사.분석해 보았다. 그 결과 fly ash는 일반폐기물로 분류됨을 확인하였고, fly ash의 PH는 오염 물질 배출허용 기준치보다 알칼리성을 강하게 띠고 있어 문제가 되고 있으나 이는 산성화된 토양을 중성화하는 토량개량재로서 fly ash의 역할을 기대할 수 있으며, 그 외에는 오염물질 배출허용 기준치에 훨씬 못 미치는 것으로 나타나고 있다. 더구나 석탄재의 열악한 역학적 특성을 개량하기 위하여 사용되는 정도의 소량의 첨가제(시멘트 또는 석회 등)에 의하여 강도 및 내구성 증가, 투수성 억제는 물론 문제가 되는 수소이온농도가 오염물질 배출허용기준(pH 5.8~8.6) 이하로 낮아져, 석탄재의 건설재료로서의 활용에 있어 환경적인 문제의 여지는 없을 것으로 여겨진다.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2003년도 봄 학술발표회 논문집
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• pp.485-492
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• 2003

In this study, We peformed on the effective evaluation of slope berm construction using slope stability analysis programs. The effective evaluation of slope berm construction was performed by stability of slope and economy of construction. This time, used slope stability analysis programs are Talren97 that use Limit equilibrium method (LEM) and FLAC-SLOPE that use finite difference method (FDM), and carried out using Rocfall program to evaluate slope stability by rockfall occurrence.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2023년도 봄 학술논문 발표대회
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• pp.347-348
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• 2023

In construction sites, small-scale construction quantities or limited work hours below the daily work volume may occur due to on-site conditions. For small-scale quantities, the input of equipment and labor is designed based on an hourly basis in the invoice, resulting in a difference from the actual cost. In this study, we aim to explore solutions from the perspective of construction cost standards to secure appropriate construction costs for small-scale and time-limited construction sites. Firstly, to preserve the basic construction costs on-site, we established standards where half the cost would be charged for construction quantities below four hours and a full day's cost would be designed for construction quantities between four to eight hours. Additionally, realistic construction cost calculation standards are expected to be provided by realizing a surcharge rate for work hour limitations to secure appropriate construction costs.

• 한국원자력학회:학술대회논문집
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• 한국원자력학회 2002년도 춘계공동학술발표회요약집
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• pp.201.1-201
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• 2002

• Kyungpook Mathematical Journal
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• 제29권2호
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• pp.203-236
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• 1989