• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2007년 가을학술발표회
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• pp.528-541
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• 2007

To get the possible for management and maintenance, it was analyzed the deformation characteristics, such as crest of embankment and concrete face slab, and leakage of concrete faced rockfill dams (CFRD). There are trends that embankment deformation depends on intact strength used rockfills rather than dam height, deformation normal to concrete face slab during the first reservoir filling is occurred more than 80% of the total deformation in general, and the magnitude and trend of concrete face slab deformation is similar to post-construction crest settlement. The results showed that the range of post-construction crest settlement suggested by Sherard and Cooke (1987), and Clements (1984) had a good agreement in the cases using rockfill with very high intact strength, but it had a trend which underestimated crest settlement in the cases using rockfill with medium to high intact strength. The maximum leakage rate in general was observed during the first reservoir filling and long-term leakage rate was rapidly increased when the dam height exceeds approximately 120m.

• 한국지진공학회논문집
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• 제21권5호
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• pp.255-264
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• 2017

Dynamic numerical simulation of pile-supported slab track system embedded in a soft soil and embankment was performed. 3D model was formulated in a time domain to consider the non-linearity of soil by utilizing FLAC 3D, which is a finite difference method program. Soil non-linearity was simulated by adopting the hysteric damping model and liner elements, which could consider soil-pile interface. The long period seismic loads, Hachinohe type strong motions, were applied for estimating seismic respose of the system, Parametric study was carried out by changing subsoil layer profile, embankment height and seismic loading conditions. The most of horizontal permanent displacement was initiated by slope failure. Increase of the embedded height and thickness of the soft soil layer leads increase of member forces of PHC piles; bending moment, and axial force. Finally, basic guidelines for designing pile-supported slab track system under seismic loading are recommended based on the analysis results.

• 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.

• 농업과학연구
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• 제50권3호
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• pp.469-484
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• 2023

In this study, three types of structures-stepped gabion retaining walls, vertical gabion retaining walls, and parapets-were installed on the dam floor crest to prevent the overflow of deteriorative homogeneous reservoirs. The acceleration response, displacement behavior, and pore water pressure ratio behavior were compared and evaluated using shaking-table model tests. The experimental conditions were set to 0.154 g in consideration of the domestic standard and the seismic acceleration range according to the magnitude of the earthquake, and the input waveform was applied with Pohang, Gongen, and artificial earthquake waves. The acceleration response according to the design ground acceleration increased as the height of the embankment increased, and the observed value were larger in the range of 1.1 to 2.1 times the input acceleration for all structures. The horizontal and vertical displacements exhibited maximum values on the upstream slope, and the embankment was evaluated as stable and included within the allowable range for all waveforms. The settlement ratio considering the similarity law exhibited the least change in the case of the parapet structure. The amplification ratio was 1.1 to 1.5 times in all structures, with the largest observed in the dam crest. The maximum excess pore water pressure ratio was in the range of 0.010 - 0.021, and the liquefaction evaluation standard was within 1.0, which was considered very stable.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2002년도 가을 학술발표회 논문집
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• pp.705-712
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• 2002

Geotextile tube is environmentally sustainable technology and has been applied in hydraulic and coastal engineering applications. Geotextile tube is composed in permeable fabrics and Inside dredged materials, and hydraulically or mechanically filled with dredged materials. These tube are generally about 1.0m to 2.0m in diameter, through they can be sized for any application. The tubes can be used solely, or stacked to add greater height and usability. Stacked geotextile tubes will create by adding the height necessary for some breakwaters and embankment, therefore increasing the usability of geotextile tubes. This paper presents the hydrodynamic behavior of stacked geotextile tube by hydraulic model tests. The hydraulic model test conducted by structural condition and wave conditions. Structural condition is installation direction to the wave(perpendicular band 45$^{\circ}$), and wave condition is varied with the significant wave height ranging from 3.0m to 6.0m. Based on the test results, the hydrodynamic behaviors such as structural stability, wave control capacity, and strain are interpreted.

• 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.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2000년도 봄 학술발표회 논문집
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• pp.173-182
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• 2000

To find axial and lateral responses of impact-driven H piles in embankment(SM), the H piles are instrumented with electric strain gages, dynamic load test is performed during driving, and then the damage of strain gages is checked simultaneously. Axially and laterally static load tests are performed on the same piles after one to nine days as well. Then load-settlement behavior is measured. Furthermore, to find the set-up effect in H pile, No. 4, 16, 26, and R6 piles are restriked about 1, 2, and 14 days after driving. As results, ram height and pile capacity obtained from impact driving control method become 80cm and 210.3∼242.3ton, respectively. At 15 days after driving, allowable bearing capacity by CAPWAP analysis, which 2.5 of the factor of safety is applied for ultimate bearing capacity, increases 10.8%. Ultimate bearing capacity obtained from axially static load test is 306∼338ton. This capacity is 68.5∼75.7% at yield force of pile material and is 4∼4.5 times of design load. Allowable bearing capacity using 2 of the factor of safety is 153∼169ton. Initial stiffness response of the pile is 27.5ton/mm. As the lateral load increases, the horizontal load-settlement behaves linearly to which the lateral load reaches up to 17ton. This reason is filled with sand in the cavity formed between flange and web during pile driving. As the result of reading with electric strain gages, flange material of pile is yielded at 19ton in horizontal load. Thus allowable load of this pile material is 9.5ton when the factor of safety is 2.0. Allowable lateral displacement of this pile corresponding to this load is 23∼36mm in embankment.

• 한국농공학회논문집
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• 제55권6호
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• pp.155-165
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• 2013

Recently, geotextile tube method can be widely applied to the river, costal and marine in the construction field, such as embankment, groin, breakwater, dyke structures and so on, in advanced countries of the world. And that has been constructed at the temporary road for incheon, ilsan-bridge construction and coast erosion protection in republic of korea. Geotextile tube is a tube shaped geotextile product and hydraulic pumping filled with dredged soils. In this paper, the numerical analysis was performed to investigate the behavior of geotextile tube with various properties of material character, shape condition, construction pressure and so on. Also, the field test was conducted in order to identify the construction ability of Samangum waterproof embankment using geotextile tube. According to the applied of field test, geotextile tube was 65 m long and 4.0 m diameter. Also, the permeability coefficient and ultimate tensile strength of geotextile tube is $1.6{\times}10^{-1}$ cm/sec and 205.26 kN/m, respectively. As a result of filed test, when filled, geotextile tube does not attain the same as its unfilled theoretical diameter, but may reach approximately of 55 percent of the theoretical diameter. At the time, geotextile tubes were 12.56 m in circumference and filled to a height of about 2.2 m. This paper presents case study on field application and behavior analysis of the saemangum waterproof embankment donggin 1 division construction using geotextile tube.

• 한국지반환경공학회 논문집
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• 제13권9호
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• pp.17-29
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• 2012

각종 연직배수재가 설치된 연약지반의 전단강도, 지반변형의 특성을 조사하기 위해 우리나라 서해안과 남해안 지역에서 계측관리가 실시된 13개 연약지반현장 200개소에서 계측자료를 수집하였다. 먼저 연약지반의 침하량과 측방변위량과의 관계를 성토 초기 단계, 성토 완료 단계 및 성토 완료 후 단계의 세 단계로 구분하여 조사하였다. 다음으로 성토압과 성토고가 연약지반의 비배수전단강도와 어떤 관계에 있는가를 조사하였다. 검토결과, 침하의 증가량에 대한 수평변위의 증가량은 성토 초기 단계에서는 작았으나 점차 증가하여 성토 완료 단계에서 가장 크게 발생되었다. 그러나 성토 완료 후에도 침하량은 계속 증가하고 있었으며 수평변위는 거의 수렴하였으므로 대부분의 측방유동은 성토시공 중에 발생되었다. 침하량증분에 대한 수평변위증분의 비는 성토 초기 단계에서 20% 정도로 Tavenas et al.(1979)이 제시한 값과 일치하였으나 성토 완료 단계에서는 Tavenas et al.(1979)이 제시한 값의 절반 정도인 50%밖에 나타나지 않았다. 그리고 성토 완료 후 단계에서는 1%에서 9% 사이로 아주 작게 발생되어 Tavenas et al.(1979)이 제시한 값과 상당한 차이를 보였다. 모든 현장에서 설계성토고가 초기비배수강도 상태에서의 항복성토고보다 높은 상태였으므로, 연약지반 속에 전단변형 내지 전단파괴가 발생될 것이 예상되었다. 그러나 강도가 증가된 후에는 모든 현장에서 설계 성토고가 항복성토고보다 낮게 되어 안전한 성토시공이 가능하였던 것으로 판단된다. 도로성토시공을 안전하게 실시하기 위해서는 성토하중이 초기비배수전단강도의 5.14배가 넘지 않도록 하여야 하며 증가된 비배수전단강도의 3.0배 이하가 되도록 설계하여야 한다.

• 한국지반공학회논문집
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• 제19권1호
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• pp.5-19
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• 2003

본 연구에서는 인접 성토로 인하여 측방유동이 발생하는 연약한 점성토 지반에 시공된 교대말뚝기초를 원심모형실험으로 재현하여 지반조건과 성토지반의 시공속도에 따른 교대말뚝기초의 거동특성을 분석하였다. 이를 위해 지반조건과 성토지반 시공속도를 교대말뚝기초의 측방유동에 가장 중요한 영향을 미치는 변수로 선정하여 총 6 종류의 원심모형실험을 실시하였다. 본 실험에서 지반조건은 점성토 지반의 두께와 지층단면에 따라 세 가지 종류로 구분하였으며 성토하중 재하조건은 한계성토고까지 단계적으로 재하하는 방법(1m/30일, 1m/15일)과 한계성토고에 해당하는 하중을 급속재하 하는 방법으로 나누어 고려하였다. 그 결과 동일한 조건하에서 측방유동을 받는 교대말뚝기초의 비배수 단기거동과 장기거동을 파악하기 위해 성토하중 재하단계와 성토 후 압밀이 약 80% 진행된 단계에서의 지반-말뚝 거동특성을 비교ㆍ 분석하였다. 본 연구 결과, 편차 성토하중으로 인해 연약지반상 교대말뚝기초에 발생하는 측방유동압은 단계별 성토하중 재하시 사다리꼴 분포형태와 유사하였으며 이때 발생하는 최대 측방유동압($P_{max}$)과 편차 성토하중($\gamma$ H)의 비($\alpha$)는 비배수 상태인 단기거동시에는 0.75, 압밀이 약 80% 진행된 장기거동시에는 0.35 정도로 나타남을 알 수 있었다.