• 한국안전학회지
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• 제15권1호
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• pp.146-152
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• 2000

To estimate the behavior of reinforced and unreinforced embankment constructed on a impermeable foundation ground, a laboratory model test was performed for two types of soils and water level increasing velocity of a flood period. The experiment models were constructed with slopes of water level is 1.25cm/min, 2.5cm/min each. From model test results, as the slope of reinforced and unreinforced embankment was the slower, the more seepage line rised. In the unreinforced embankment, the rising velocity of water level was the faster, the larger the embankment failure was. And the reinforced embankment with geotextile was the more safe than the unreinforced embankment for seepage force.

• 한국농공학회논문집
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• 제52권2호
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• pp.59-66
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• 2010

This study was performed to develop the embankment protection method that can reduce demage by prevention of embankment loss and collapse from overflow due to heavy rain and flood. For overflow test, model dam was prepared and embankment behaviors were monitored with the established piezometer and strain meter during overflow. As a result of overflow test for model dam, in case of embankment without waterproof mat, the lower end of embankment was collapsed within 40 seconds after beginning of overflow. On the other hand, in case of embankment with waterproof mat, embankment collapse didn't occurred during overflow. Accordingly, establishment of waterproof mat for embankment showed that be absolutely effective for the embankment protection during overflow in reservoir. Also, it showed that the minimum establishment range of waterproof mat to prevent embankment collapse in reservoir is from maximum storage level to the lower end of embankment.

• 한국지반공학회논문집
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• 제16권4호
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• pp.171-181
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• 2000

성토지지말뚝 상부의 성토지반내에서 발생되는 지반아칭효과에 의하여 성토하중이 말뚝에 전달되는 효과를 조사하면서 제안된 이론해석의 신뢰성을 확인하기 위하여 일련의 모형실험을 수행하였다. 본 모형실험에서 말뚝은 성토 아래에 일렬로 수열의 줄말뚝으로 설치하였으며, 말뚝캡보는 성토의 길이방향에 직각방향으로 말뚝두부에 설치하였다. 성토재의 하중전달에 가장 큰 영향을 미치는 요인으로는 말뚝캡보사이의 간격과 성토고를 들 수 있다. 이전의 이론적인 연구에 의해 제안된 지반아치의 반경보다 약 33%정도 큰 최소소요성토고보다 높게 성토를 실시할 경우 지반아치는 완벽하게 발생될 뿐만 아니라, 실험치와 이론치는 잘 일치함을 모형실험결과 확인할 수 있다. 모형말뚝캡보에 작용하는 성토하중의 분담률은 말뚝캡보사이의 간격이 증가함에 따라 감소하는 반면, 성토고가 높아짐에 따라 증가하였다. 따라서, 설계시 말뚝의 성토하중지지효과를 극대화시키기 위해서는 성토고를 충분히 높게한 상태에서 말뚝캡보의 간격비를 감소시켜야 한다. 여기서 말뚝캡보의 간격비를 감소시키려면 말뚝캡보사이의 간격을 감소시키거나 말뚝캡보의 폭을 증가시켜야 한다.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2009년도 세계 도시지반공학 심포지엄
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• pp.956-962
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• 2009

A high embankment is generally constructed by dividing into several sub-embankments. Unlike any soil embankment, a rock embankment is constructed by means of dynamic compaction. Such a sub-embankment and dynamic compaction may induce an increase of pressure at the lower part of embankment and cause a different behavior of ground from initial status. In this study, settlement of a high rock embankment is estimated using a hyperbolic model taking into construction history. The results from prediction are compared with those obtained from field measurements and large plate loading tests.

• Geomechanics and Engineering
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• 제31권3호
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• pp.319-328
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• 2022

Ensuring the integrity of a country's infrastructure is necessary to protect surrounding communities in case of disaster. Embankment dam systems across the US are an essential component of infrastructure, referred to as lifeline structures. Embankment dams are crucial to the survival of life and if these structures were to fail, it is imperative that states be prepared. Southern California is particularly concerned with the stability of embankment dams due to the frequent seismic activity that occurs in the state. The purpose of this study was to create a numerical model of an existing embankment dam simulated under seismic loads using previously recorded data. The embankment dam that was studied in Los Angeles, California was outfitted with accelerometers provided by the California Strong Motion Instrumentation Program that have recorded strong motion data for decades and was processed by the Center for Engineering Strong Motion Data to be used in future engineering applications. The accelerometer data was then used to verify the numerical model that was created using finite element modeling software RS2. The results from this study showed Puddingstone Dam's simulated response was consistent with that experienced during previous earthquakes and therefore validated the predicted behavior from the numerical model. The study also identified areas of weakness and instability on the dam that posed the greatest risk for its failure. Following this study, the numerical model can now be used to predict the dam's response to future earthquakes, develop plans for its remediation, and for emergency response in case of disaster.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 1988년도 학술세미나 강연집
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• pp.3-67
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• 1988

Model studies on the response of homgeneous earth embankment dams subjected to strike-slip fault movement have been penomed via centrifuge and finite element analysis. The centrifuge model tests have shown that crack development in earth embankment experiences two major patters: shear failure deep inside the embankment and tension failure near the surface. The shear rupture zone develops from the base level and propagates upward continuously in the transverse direction but allows no open leakage chnnel. The open tensile cracks develop near the surface of the embankment, but they disappear deep in the embankment. The functional relationship has been developed based on the results of the centrifuge model tests incorporating tile variables of amount of fault movement, embankment geometry, and crack propagation extent in earth des. This set of information can be used as a guide line to evaluate a "transient" safety of the duaged embankment subjected to strike-slip fault movement. The finite element analysis has supplemented the additional expluations on crack development behavior identified from the results of the centrifuge model tests. The bounding surface time-independent plasticity soil model was employed in the numerical analysis. Due to the assumption of continuum in the current version of the 3-D FEM code, the prediction of the soil structure response beyond the failure condition was not quantitatively accurate. However, the fundamental mechanism of crack development was qualitatively evaluated based on the stress analysis for the deformed soil elements of the damaged earth embankment. The tensile failure zone is identified when the minor principal stress of the deformed soil elements less than zero. The shear failure zone is identified when the stress state of the deformed soil elements is at the point where the critical state line intersects the bounding surface.g surface.

• 농업과학연구
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• 제40권3호
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• pp.243-252
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• 2013

This study was carried out to investigate safety evaluation of agricultural reservoirs due to raising the embankment. The seepage analysis and large-scale model test were performed to compare and analyze the pore water pressure(PWP), leakage quantity, settlement and piping phenomenon in the inclined core type and the vertical core type embankments. The PWP after raising the embankment showed smaller than before raising the embankment and the stability for piping after raising the embankment. The allowable seepage quantity and the allowable leakage for the steady state and transient conditions is within the range of safe management standard. After raising the embankment in the inclined core, there was no infiltration by leakage. For the vertical core, the PWP showed a large change by faster infiltration of pore water than in the inclined core. In a rapid drawdown, inclined core was remained stable but the vertical core showed a large change in PWP. Settlement after raising the embankment showed larger amounts of settlement than before raising the embankment. The leakage quantity before raising the embankment and the inclined core type showed no leakage. From the result, an instrument system that can accurately estimate a change of PWP shall be established for the rational maintenance and stabilization of raising the embankment for agricultural reservoirs.

• 한국지반신소재학회논문집
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• 제9권3호
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• pp.9-18
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• 2010

토목섬유보강 성토지지말뚝시스템에서의 하중전이 특성을 규명하기 위하여 일련의 모형실험을 실시하였다. 모형토조에 단독캡 말뚝을 설치하고, 토목섬유를 포설한 후 성토를 실시하였다. 연약지반 대체재료로서 스펀지고무를 사용하였다. 실험결과 성토지지말뚝시스템의 효율은 일정한 말뚝간격비에서는 성토고가 증가할수록 비선형적으로 증가하여 이후 일정한 값에 수렴하는 경향을 나타내었다. 또한 성토고가 일정한 조건에서는 말뚝간격비가 증가할수록 효율의 크기는 감소하였다. 토목섬유를 보강한 경우, 무보강시와 비교하여 말뚝으로 전이되는 하중이 증가하는 것으로 나타났다. 이는 토목섬유의 보강이 연약지반의 거동을 억지하는데 효과가 있음을 나타내는 것이다. 결국 토목섬유보강 성토지지말뚝시스템에서의 하중전이 특성은 말뚝캡 설치간격, 성토고, 지반의 강도정수 및 토목섬유 강성 등에 복합적으로 영향을 받음을 알 수 있다.

• 한국안전학회지
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• 제14권4호
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• pp.158-167
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• 1999

In parallel flow condition, to estimate the stability of the extended embankment constructed on a permeable foundation ground, a laboratory model test was performed due to extended materials and water level increasing velocity of a flood period. A laboratory model test was peformed for different permeability coefficients ($K_1=2.0{\times}10^{-5}cm/sec,\;K_2=1.5{\times}10^{-4}cm/sec,\;K_3=2.3{\times}10^{-3}cm/sec$) using seepage. The fluctuation of water level occurring to an extended embankment was analyzed by laboratory model tests as vary the increasing velocity of water level with 0.6cm/min, 1.2cm/min, 2.4cm/min respectively. In analysis results, the increase of water level into embankment occurs rapidly because seepage water moving along with a permeable soil flow into embankment. The larger the permeability coefficient of an extended part is the longer initial seepage distance, and the exit point of downstream slope is gradually increased and then shows unstable seepage behavior as occurring partial collapse. As the increasing velocity of water level increase, the initial seepage line is formed low, and the discharge increases. Therefore, the embankment extended by a lower permeable soil than existing embankment shows stable seepage behavior because an existing embankment plays a role as filter for an extended part.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2002년도 추계학술대회 논문집(I)
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• pp.601-607
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• 2002

Infiltration of rainfall causes railway embankment to be unstable and may result in failure. Basic relationship between the stability of railway embankment and rainfall introducing the partial saturation concept of ground are defined to analyze the stability of embankment by rainfall. A pressure plate test is also peformed to obtain soil-water characteristic curve of unsaturated soils. Based on this curve, the variables in the shear strength function and permeability function are also defined. These functions are used fur the numerical model for evaluation of railway embankments under rainfall. As comparing the model and case studies, the variation of shear strength, the degree of saturation and pore-water pressure for railway embankment during rainfall can be predicted and the safety factor of railway embankment can be expressed as the function of rainfall amount namely rainfall index. Therefore, the research on safety factor on railway embankment considering train speed and rainfall infiltration with the variation of rainfall intensity and rainfall duration was carried out in this paper.