• 한국안전학회지
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• 제15권2호
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• pp.103-110
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• 2000

This paper deal with the stability evaluation and suggestion of progressive failure slope in biotite granite area of Andong. Based on geological site investigation and field test, stability analysis of slope was performed in conjunction with limit equilibrium methods and stereographic projection. Additionally, initial design and construction procedure was critically evaluated. Series of the slope stability analysis reveals the detection of local wedge and plane failure under the current slope condition. It is additionally appeared that a certain synthetic behavior of circle and plane failure exists on the right spot where the overall failure's going in progress. In order to construct more stable slope based on the suitability for the real state of the slope circumstances, this study issues a solution to eliminate the primary factors which cause the instability, by means of the grade of weathering and RMR classification of rock mass.

• 복합신소재구조학회 논문집
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• 제7권1호
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• pp.25-31
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• 2016

Bond stress between cast-in-place ductile fiber reinforced cementitious composites and CFRP plank were experimentally analyzed. As failure shape, the mixture of failure between CFRP plank and epoxy, and failure between concrete and epoxy was shown. In case of RFCON from the suggested simple bond slip relationship, the maximum average bond stress was 5.39MPa, the initial slope was 104.09MPa/mm, and the total slip length was 0.19mm. PPCON showed the maximum average bond stress of 4.31MPa, the initial slope of 126.67MPa/mm, and the total slip length of 0.26mm, while RFCON+ appeared to have 8.71MPa, 137.69MPa/mm, 0.16mm. PPCON+ had 6.19MPa maximum average bond stress, 121.56MPa/mm initial slope, and 0.34mm total slip length. To comprehend the behavior of composite structure of FRP and concrete, local bond slip relation is necessary, and thus a simple relation is suggested to be easily applied on hybrid composite system.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2009년도 세계 도시지반공학 심포지엄
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• pp.677-694
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• 2009

While the budget has been allocated more for repairs and reinforcements, casualties are gradually increased due to slope disaster. Slope disaster causes road damaged as well as casualties. It also causes significant social and economic loss. The measurement device, which is installed inside ground of slope like inclinometer, has the high loss rate when slope is being slided. The electric type and the vibrating wire type have low durability because of corrosion. To cover the demerit of the present slope monitoring, the measurement method using the Multi-Antenna GPS has been developed. The Multi-Antenna GPS has been installed in the local slope as the regular monitoring system for slope. Although the initial cost of the Multi-Antenna GPS for installation is high, the additional cost is low. So it is the suitable method for large slope. The regular monitoring system using the Multi-Antenna GPS is the suitable measurement method for watching slope collapse, which is occurred widely, because it is economical, has high durability, and collects data with high resolution.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2002년도 봄 학술발표회 논문집
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• pp.509-516
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• 2002

Rainfall-induced landslides in a weathered granite soil slope have mostly relative shallow slip surfaces above the groundwater table The pore-water pressure of soil above the groundwater table is usually negative. This negative pore-water pressure(or matric suction) has been found to make a large contribution to the slope stability. Therefore, the variation of in-situ matric suction profiles with time in a soil slope should be understood. In this study, a field measurement program was carried out from June to August, 2001 to monitor in-situ matric suctions and volumetric water contents in a weathered granite soil slope. The influence of climatic conditions on the variation of in-situ matric suctions could be found to decrease rapidly with depth. It could be found that decrement of matric suction induced by precipitation is affected not only by the amount and duration of rainfalls but also by the initial matric suction just prior to rainstorms. The soil-water characteristic from the field monitoring tends toward the wetting path of SWCC obtained from the laboratory test.

• 한국농공학회논문집
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• 제55권6호
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• pp.37-46
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• 2013

Many factors about the stability for the reservoir embankments is determined when the facility is completed. Therefore the initial design of the embankment is important. Many researchers focused the effect of soil parameters although the cross section greatly affects the stability and can be controlled in design step. The objective of this research is to analysis of the effects for the safety factor of slope and seepage according to change cross-section in embankment. As a result, the quantity of seepage decreased as the gradient of downstream slope decreased and was proportional to the height of embankments. There was a linear relationship between the gradient of slope and the safety factor of slope. However the gradient of slope did not affect other side slope. All in a relationship, regressive equations with a high correlation coefficient were calculated and can be applied the simple estimation method of the stability using the cross-section. As results of analyzing the sensitivity, the friction angle and permeability critically effect for the slope stability and the seepage, respectively. The effect of the slope gradient was similar to major soil properties.

• Structural Engineering and Mechanics
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• 제60권1호
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• pp.21-30
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• 2016

In this paper two procedures for determination of the elastic curve of the simply and multiple supported beams are developed. Determination of the elastic curve is complex as it requires to solve a strong nonlinear differential equation with given boundary conditions. For numerical solution the initial guess of the slope at the end of the beam is necessary. Two procedures for obtaining of the initial guess are developed: one, based on transformation of the supported beam into a clamped-free one, and second, on the linearization of the problem. Procedures are applied for calculating of elastic curve of a simply supported beam and a beam with three supports. Obtained results are compared. Advantages and disadvantages of both methods are discussed. It is proved that both suggested procedures give us technically accurate results.

• 한국지구과학회지
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• 제35권5호
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• pp.362-374
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• 2014

This study investigated the initial mass function (IMF) and star formation history of high-mass stars in the Small Magellanic Cloud (SMC) using a population synthesis technique. We used the photometric survey catalog of Lee (2013) as the observable quantities and compare them with those of synthetic populations based on Bayesian inference. For the IMF slope (${\Gamma}$) range of -1.1 to -3.5 with steps of 0.1, five types of star formation models were tested: 1) continuous; 2) single burst at 10 Myr; 3) single burst at 60 Myr; 4) double bursts at those epochs; and 5) a complex hybrid model. In this study, a total of 125 models were tested. Based on the model calculations, it was found that the continuous model could simulate the high-mass stars of the SMC and that its IMF slope was -1.6 which is slightly steeper than Salpeter's IMF, i.e., ${\Gamma}=-1.35$.

• 대한토목학회논문집
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• 제33권3호
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• pp.1027-1035
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• 2013

사면안정 해석 시, 사면파괴의 주원인인 강우사상의 현실적 접목을 위하여 본 연구에서는 다음 두 가지 방법을 채택하였다. 하나는 시간에 따른 강우량 변화의 영향을 무시한 기존의 설계강우 방식인 I.D.F(Intensity-Duration-Frequency)곡선을 이용하는 방법이며, 다른 하나는 시간의 영향을 고려하여 강우사상을 표현한 Huff 방법이다. 먼저 I.D.F 방법의 강우사상을 적용하여 선행강우효과를 나타내는 초기흡수력의 변화에 따른 사면의 안전율의 변화를 알아보았다. 또한, 두 강우사상의 방식을 적용하여 강우사상이 사면의 안전율 변화에 미치는 영향을 규명하고자 하였다. 그 결과, Huff 방법의 강우사상이 I.D.F 방법보다 더 현실적으로 사면의 안전성 평가가 이루어 질 수 있음을 확인할 수 있었다.

• 실천공학교육논문지
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• 제11권2호
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• pp.291-303
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• 2019

본 연구의 목적은 대학생의 성취지향성목표가 대학생활만족도와 대학 소속감에 미치는 영향에 대해 분석하는 것이다. 3년에 걸친 종단 자료를 바탕으로 시간의 흐름에 따른 변화를 분석하기 위해 본 연구는 잠재성장 모형을 활용하였다. 그 결과는 성취목표지향성 개념 중 숙달접근과 숙달회피는 대학생활만족도 초기값에는 영향을 주고 있으나 시간의 흐름에 따른 변화는 없었다. 반면, 수행접근은 대학생활만족도의 초기값에 영향을 주지 못하였지만 시간이 흐름에 따른 변화율에는 긍정적인 영향을 주었다. 그리고 수행회피는 초기값과 변화율 모두 영향을 주지 못하였다. 성취목표지향성 요인들이 소속감에 미치는 영향도 조사한 결과 숙달접근과 숙달회피는 대학생활만족도에 미치는 형태와 비슷하게 소속감 초기값에도 영향을 주었다. 다만 수행접근은 대학생활만족도의 변화율에는 영향을 주었지만 소속감 초기값에는 영향을 주지 않는 것으로 나타났다.

• 한국지반환경공학회 논문집
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• 제24권10호
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• pp.15-23
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• 2023

본 연구에서는 국내의 대표적 풍화토인 편마풍화토에 점토함유량 0%, 5%, 10%의 혼합토로 조성된 비탈면에 대해 강우 시 침투거동을 조사하고, 강우침투로 인한 불포화 비탈면의 안정성을 검토했다. 이를 위해 본 연구에서는 불포화 함수특성시험을 통해 함수특성곡선을 획득했고, 포화 삼축압축시험을 통해 강도정수를 얻었다. 얻어진 결과를 토대로, 침투해석과 안정해석을 통해 비탈면의 강우침투로 인한 포화대 형성과 안전성에 점토함유량과 선행강우 효과를 나타내는 초기흡수력이 미치는 영향에 대해 조사하였다. 그 결과, 지반의 초기흡수력이 높을수록 비탈면의 포화대 형성이 늦춰졌다는 것을 알았다. 또한 점토함유량이 증가할수록 지반의 전단강도 증대와 더불어 강우침투에 대한 저항성을 높이는 효과를 가지며, 비탈면의 안전성을 크게 향상시킨다는 것을 알 수 있었다.