• Journal of Ship and Ocean Technology
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• 제8권2호
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• pp.29-40
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• 2004

Interaction of grounded ice ridges with underlying seabed is one of the major considerations in the design of Arctic pipeline system. Previously several ice scour models were developed by researchers to describe the ice scour-seabed interaction mechanism. In this paper, a parametric study on ice scouring mechanism is performed and the limitation of ice scour-seabed interaction models is discussed. Simple laboratory tests are carried out and then the shape pattern of deposited soil around the ice is redefined. New ice scour model assumes trapezoidal cross section based on the field observation data. Ice scour depth and soil resistance forces on seabed are calculated with varying the keel angle of a model ice ridge.

• 한국해양공학회지
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• 제11권2호
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• pp.1-10
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• 1997

The interaction of ground ice features with underlying seabed is one of the major considerations in the design of Arctic pipeline systems. Regarding the development of offshore gas field near Sakhalin Island, which is an ice-infested area, in this paper an ice scour model to determine the burial depth of Arctic offshore pipeline is studied. Using a simplified ice-seabed interaction process, ice scour depth is easily estimated. This nonlinear numerical model can simulate the scouring process for various enviromental parameters such as ice mass, incoming velocity, soil strength. This study also deals with interaction forces during the scouring process in sloping seabed conditions and discusses the ice loads that are transmitted through the seabed soil.

• 한국습지학회지
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• 제16권4호
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• pp.453-462
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• 2014

The levee and bridge pier in estuary of the Hangang River are exposed in a dangerous condition due to bank erosion and local scouring occurred since the summer season in 2011. At first, it is presumed that the high sandbar formed in river channel of the study area was an important element in the occurrence of bank erosion and local scouring. It can be presumed that the record-breaking depth of freezing due to cold wave for the long term during the winter season between 2010 and 2011 as well as the heavy intensive rainfall of 2011 had a decisive effect on the first damage of A section. The second damage of B section mainly occurred around the bridge pier constructed on the high water channel before it was washed away during the winter season between 2011 and 2012. It is considered that the second damage was caused by ice formation and ice floes.

• Journal of Ship and Ocean Technology
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• 제7권4호
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• pp.1-15
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• 2003

The motion of passively floating body, whose keel can have a contact with seabed soil, is under the consideration. The body simulates ice ridge floating in shallow water. The force of seabed soil reaction applied to the grounded keel is estimated taking into account soil embankment near the grounded keel. Two-dimensional trajectories of body motion, the shape of the grooves in seabed and the height of soil embankment are calculated when the motion of the body is caused by semidiurnal $M_2$ tide. The influence of wave amplitude and bottom slope on the shapes of body trajectory and the grooves are analyzed.

• Journal of Information Processing Systems
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• 제15권6호
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• pp.1350-1364
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• 2019

The ice damage occurs frequently in cold and dry region of western China in winter ice period and spring thaw period. In the drift ice condition, it is easy to form different extrusion force or impact force to damage tunnel lining, causing project failure. The failure project could not arrive the original planning and construction goal, giving rise to the water allocation pressure which influences diversion irrigation and farming production in spring. This study conducts the theoretical study on contact-impact algorithm of drift ices crashing diversion tunnel based on the symmetric penalty function in finite element theory. ANSYS/LS-DYNA is adopted as the platform to establish tunnel model and drift ice model. LS-DYNA SOLVER is used as the solver and LS-PREPOST is used to do post-processing, analyzing the damage degrees of drift ices on tunnel. Constructing physical model in the experiment to verify and reveal the impact damage mechanism of drift ices on diversion tunnel. The software simulation results and the experiment results show that tunnel lining surface will form varying degree deformation and failure when drift ices crash tunnel lining on different velocity, different plan size and different thickness of drift ice. The researches also show that there are damages of drift ice impact force on tunnel lining in the thawing period in cold and dry region. By long time water scouring, the tunnel lining surfaces are broken and falling off which breaks the strength and stability of the structure.

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 2001년도 봄 학술발표회 논문집
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• pp.121-127
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• 2001

To investigate the stability and integrity of offshore structures, it is necessary to estimates the significant ocean environmental loadings. They include hydrostatic pressure, wind, wave, current, tide, ice, earthquake, temperature, marine growth and scouring. Waves are of major importance among them because of the large forces acting on submerged parts of the structure caused by accompanying water motions. For the comparison of stress and deflection analysis tools, a vertical pile is applied under environmental loads. The analysis is concerned with SACS(Structural Analysis Computer System), ANSYS and C program. SACS and C program have nearly the same results but not ANSYS. This study shows the comparison of results obtained from 3 different approaches.

• 한국지역지리학회지
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• 제17권4호
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• pp.416-431
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• 2011

지리산과 한라산을 대상으로 산악 국립공원 등산로의 훼손 유형을 요인별로 조사하였다. 등산로 훼손은 침식프로세스가 진행되는 장소에 따라 노면 저하, 측벽 후퇴, 노면 확대 및 분기로 구분할 수 있다. 노면 저하와 측벽 후퇴가 주로 자연적인 침식 요인에 의해 일어나는 훼손 유형인 반면 노면 확대 및 분기는 인위적인 답압으로 발생하는 훼손 유형이다. 노면 저하를 일으키는 가장 탁월한 프로세스는 우세이며, 측벽 후퇴는 등산로의 물리적 환경에 따라 우세, 서릿발작용, 취식, 도목, 동물작용 등 탁월한 프로세스가 달라진다. 노면 확대 및 분기는 탑압을 일으키는 원인에 의해 유형화할 수 있다. 지표류에 의해 등산로 노면이 낮아지는 과정에서 드러난 나무뿌리, 자갈 및 암반과 국지적인 세굴로 인하여 노변에 만들어진 높낮이차 등 우세와 관련하여 발생하는 훼손 사례가 많다. 또한 평탄면 등산로에서는 물웅덩이, 산림지대의 등산로에서는 천근성 수목인 구상나무의 도목이 노면 확대 빛 분기의 주요 원인이 된다. 돌깔기 공법처럼 노변 보호공법이 오히려 등산객의 등산로 이탈을 조장하기도 하며, 보행에 불편을 주는 요소가 없더라도 등산객이 지름길을 만드는 과정에서 노면 확대 및 분기가 발생할 수 있다.