• Journal of the Korean Geotechnical Society
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• v.39 no.12
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• pp.47-60
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• 2023

At present, in South Korea, there is a growing concern regarding solar power facilities installed on slopes because they are prone to damage caused by natural disasters, such as heavy rainfall and typhoons. Each year, these solar power facilities experience soil erosion due to heavy rainfall and foundation damage or detachment caused by strong wind loads. Despite these challenges, the interaction between the ground and structures is not adequately considered. Current analyses primarily focus on the structural stability under external loads; the overall facility site's stability-excluding the solar structures-in relation to its surrounding slopes is neglected. Therefore, in this study, we use finite-difference method analysis to simulate the behavior of the foundation and piles to assess changes in lateral displacement and bending stress in piles, as well as the safety factor of sloped terrains, in response to various influencing factors, such as pile diameter, spacing between piles, pile-embedding depth, wind loads, and dry and wet conditions. The analysis results indicate that pile spacing and wind loads significantly influence lateral displacement and bending stress in piles, whereas pile-embedding depth strongly influences the safety factor of sloped terrains. Moreover, we found that under certain conditions, the design criteria in domestic standards may not be met.

• Proceedings of the Korean Society for Bio-Environment Control Conference
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• 1997.11a
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• pp.1-7
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• 1997

온실이란 식물 생육에 요구되는 태양광을 유용하게 활용하기 위하여 투명한 피복재가 사용된 구조물을 일컫는다. 온실내로 투과되는 일사량은 온실이 설치된 지역의 위도, 온실의 동방위 및 형상, 구조물의 재원, 피복재의 광학적 특성, 년중일수, 기상 조건, 지붕면의 경사각 등에 따라 변화된다. 일반적으로 겨울철에 온실내의 일사량은 식물의 정상적인 생육에 제약이 되는 요소로 작용한다. (중략)

• Proceedings of the Korean Society of Coastal and Ocean Engineers Conference
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• 1998.09a
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• pp.138-142
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• 1998

연안 구조물의 대표적인 형식인 경사식 방파제 또는 호안의 축조시에 이형블럭을 전면에 피복하여 사석부의 제체를 보호하는 형태가 널리 채택되고 있다. 이러한 연안 구조물의 축조 형식은 오랜 경험 및 피복용 이형블럭의 고안과 더불어 변형, 발전된 공법이다. 최근 물동량의 증가 및 선박의 대형화 등으로 인해 기존 항만의 확장시에 대수심 쪽으로 전진, 배치되는 추세에 있으므로 대파랑에 대응하기 위한 피복재의 중량 증가가 예상된다. (중략)

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.25 no.5
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• pp.276-284
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• 2013

A stochastic expected cost model has been suggested by combining the nonlinear cumulative damage model with the expected cost model together which can be useful for doing the preventive optimal-maintenance of the armor units of rubble-mound breakwaters. The suggested model has been satisfactorily calibrated by comparison of the results from others models, also the sensitivity analysis has been carried out in detail under the variation of the associated parameters with the model. The optimal repair times can be directly evaluated by minimizing the expected cost rates that depend on the social importances, damage intensity functions and resistance limits. Finally, the present cost model has been straightforwardly applied to the armor units of rubble-mound breakwaters. Based on the assumption of turning the damaged structure back to the state as good as new after repairs, the required optimal repair times and magnitudes can be determined quantitatively in terms of the optimum balance between the costs and benefits on the preventive maintenance.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.10
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• pp.267-273
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• 2020

Suction anchors are used for floating structures because they have advantages in installation and stability. Recently, the demand for floating structures requiring low allowable displacement has increased. Thus, it is strongly suggested that the displacement of the suction anchor be evaluated. However, conventional studies regarding suction anchors have concentrated on the capacity of the anchor, and research on the displacement of the anchor is limited. In particular, rotation is the primary behavior of a suction anchor subjected to an inclined load, and related information has been insufficient. Therefore, the main objective of this paper is to investigate the rotation behavior of a suction anchor via centrifuge model tests. The experimental parameters are the inclination of the pull-out load, anchor dimensions, and aspect ratio. The rotation values of suction anchors were compared using a series of load-rotation curves. The results show that the inclination of the load has a dominant influence on the rotation behavior of the suction anchor.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.24 no.2
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• pp.138-148
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• 2012

A stochastic reliability analysis model has been developed for evaluating the time-dependent stability performance of armor units of rubble-mound breakwaters subjected to the multiple loads of arbitrary magnitudes which could be occurred randomly. The initial structural capacities and the damage rates of armor units of rubble-mound breakwaters could be estimated as a function of the incident wave height with a given return period by using the modified Hudson's formula and Melby's formula. The structural stability performances of armor units of rubble-mound breakwaters could be analyzed in detail through the lifetime reliability investigations according to the limit states such as the serviceability or ultimate limit state and the conditions of multiple loads. Finally, repair intervals for the structural management of armor units of rubble-mound breakwaters could quantitatively be evaluated by a new approach suggested in this paper that has been based on the target probability for repair and the accumulated probabilities of failure obtained from the present stochastic reliability analysis model.

• Proceedings of the Korea Water Resources Association Conference
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• 2017.05a
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• pp.295-295
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• 2017

본 연구에서는 2차원 수리모형을 이용하여 자연하천에 보가 없는 경우, 직선 보, 경사 보 3가지 경우로 적용하여 2차원 수리분석을 실시하여 상 하류 수리특성을 검토하여 향후 하천개설 및 하도 설계의 기초자료를 제공하고자 한다. 보의 배치가 하천에 미치는 영향으로 수리특성의 변화와 유속의 변화, 토사의 이동 등 하도 내 흐름 특성의 2차원 해석결과를 도출함으로써 하도 내 횡단구조물 설치에 따른 기초적인 자료를 제공하고자 한다. 보 설치로 인한 하천 주변 친수 공간 발달로 인한 여가시설, 이동편의를 위한 도로설치 등 공간조성 설계 시 기초자료로 활용가능 할 것이다. 연구대상 하도구간은 경주 시내를 통과하는 형산강의 남천합류부 2.7km 지점부터 경주시 천북면 모아리에 위치한 모아수위관측소까지 약 8.7km 구간이다. 연구대상 유역인근에 위치한 수위관측소는 경주, 모아 관측소가 있으며 수리해석을 위한 경계조건으로 활용하였다. 연구대상 구간의 상류 부근에 경주 북천이 합류하고 있으며 현재 월령보가 경사 방향으로 설치되어져 있다. 본 연구에서는 상류경계 입력자료 계획홍수량은 형산강하천기본계획보고서(2011)을 참고하였으며, 경주 금장대 부근 합류하는 북천의 계획홍수량은 북천하천기본계획보고서(2011)를 참고하였다. 하류 경계입력자료 계획홍수위도 형산강하천기본계획보고서(2011) 참고하여 2차원 수리특성을 분석하였다. 수문량에 따른 홍수위 변화특성을 분석한 결과 풍수량과 100년 빈도 홍수량에 대해서 직각보 최대수위가 높게 분석되었으며, 유속에 대해 분석한 결과 풍수량과 100년 빈도 홍수량에 대해서 직각보가 경사보보다 물넘이 부분에서 최대유속이 빠르게 분석되었다. 또한 보가 없을 경우와 풍수 시 흐름특성을 분석한 결과 유선방향이 현재의 경사보 방향과 일치하는 것으로 분석된다. 이상의 연구결과를 검토할 때, 직각보 상류에 자전거 교량을 건설할 때 최대 유속이 발생하는 위치에는 교량기초공이나 교각 부분의 보강이 필요할 것으로 판단된다. 둔치 주변 유속변화가 발생할 수 있으므로 수위와 유속을 동시에 고려한 친수시설을 설치할 필요가 있는 것으로 판단된다.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.34 no.1
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• pp.19-25
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• 2022

Physical experiments were conducted to establish an empirical formula that predicts the wave force on the upside of the pavement behind crown wall of rubble mound seawall due to wave overtopping as well as the uplift force on the downside of the pavement. The experiments were performed by different conditions of the parapet, water depth, relative freeboard, and thickness of the armour layer. Then, the wave force on the upside and downside of the pavement behind the crown wall was analyzed. The parameters that affect the wave overtopping force and the uplift force were identified and empirical formulae were suggested for evaluating the forces on the pavement.

• Transactions of the Korean Society of Mechanical Engineers
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• v.16 no.7
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• pp.1381-1390
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• 1992

This paper presents a dynamic characteristics of flow induced vibration of circular cylinder set with inclined angle against flow direction. The effect of the cylinder bounded by spiral fin and wire on the damping of flow induced vibration is investigated, i.e., inclined angle, spiral pitch angle and number of spiral thread are studied. As the results, the cylinder with spiral fin is most effective for the damping. Also the cylinder bounded by pitch angle 50.deg. and 2 spiral thread is most effective.

• The Journal of Engineering Geology
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• v.7 no.1
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• pp.37-52
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• 1997

This paper discribes the practical application of stability analysis on the revetment structures, and four different sections of revetment structures are considered in this study. As a result of stability analysis, the the section of inclined revetment with T.T.P. block shows the highest safety factor against to the sliding failure of cap concrete block, while the section of inclined revetment with rubble stone shows the highest safety factor against to the straight and circular sliding failure. And the safety factors are increased by increasing of the rigidity of covered materials and by decreasing of the slope angle. For the safety factor of overturnning and bearing capacity, the section of inclined revetment structures shows higher safety factors than the section of vertical structures, and the safety factors are increased by decreasing of the slope angle and by increasing of the bottom width of the structures.