• 한국환경복원기술학회지
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• 제18권5호
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• pp.27-36
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• 2015

This study was conducted to grasp the effect of afforestation of cut slope using coir blocks on the improvement of scenery and the management of non point pollution source. Total four experimental tanks such as general soil slope, coir blocks, installation slope, slope refilling the inside of coir blocks slope with pebble, slope refilling the inside of coir blocks with soil and plant were installed, pollution source water was supplied and the possibility of reduction management of non point pollution source was analyzed at four items of COD, SS, T-N, T-P and main results drawn from this study are as follows. In conclusion, biodegradable materials like coir blocks and soil and plant layers are judged to be helpful in reduction management of non point pollution source inflowing to water space from land area. Thus, the reduction of non point pollution source occurring at land area is thought to be fully controlled at the cut slope, the space prior to inflowing to water ecological space like a stream or a swamp area.

• 한국재난관리표준학회지
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• 제1권2호
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• pp.67-72
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• 2008

본 논문에서는 도로확장공사 현장의 절토사면 안정검토를 위해서 몇가지 조사 및 분석을 수행하였다. 압성토 및 억지말뚝으로 보강된 절토사면의 추가 보강사례를 그 연구대상으로 하며, 절토사면에 보강된 안정화파일의 효과를 분석하기위한 시험장비 또한 설계 및 설치하였다. 결론적으로, 추가보강방법으로써 억지말뚝공법과 Earth Anchor공법을 검토한 결과, 억지말뚝공법과 Earth Anchor공법 모두 안정성은 확보하였으나 기존 보강공법의 연계성과 경제성을 고려하여 억지말뚝공법을 추가보강공법으로 선정하였다.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2008년도 춘계 학술발표회 초청강연 및 논문집
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• pp.1351-1358
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• 2008

This paper presents how the load transfer mechanism of the ground anchor affects on the stability analysis of anchored slope. The finite element analysis and the conventional limit equilibrium analysis on the anchored slope were performed and compared. The limit equilibrium analysis of the anchored slope is quite open used in design practice due to the easiness of the analysis. However, the load transfer mechanism is not considered properly for the analysis. When the failure surface passes through the bonded length of an anchor, the anchor load is disregarded and the factor of safety for the anchored slope is smaller than it should be. In this study, the load transfer distribution was incorporated into the limit equilibrium stability analysis of the anchored slope and the results were compared with the results of finite element analysis.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2006년도 춘계 학술발표회 논문집
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• pp.1-11
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• 2006

To be design the slope, the area distributed the shale or mica schist which was metamorphosed by shale must carefully consider the stability. The shale has the detrital materials of which the grain size are 1/256mm and fissility. As the reason the slope of shale is always unstable by bedding slip and fissility but also the joint and fault. Mica schist is also another unstable rock for slope by schistosity, cleavage, axial plane of a fold etc. In general shale and mica schist contain the swelling clay minerals such as smectite, vermiculite and montmorillonite. These minerals make the slope unstable. At OO tunnel construction area for the rail way of the Kyungbu high speed train, the slope of mica schist is very unstable by the distribution phenomena of the discontinuous plane such as joints which are 1-5cm spacing and thrust and strike-slip fault. By the drilling core of this area, most RQD have 0-20%.

• 지질공학
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• 제12권3호
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• pp.295-303
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• 2002

암반사면의 붕괴형태는 원호, 평면, 쐐기 또는 전도파괴로 구분하며, 각각의 붕괴는 역학적인 안정조건을 벗어날 경우 붕괴가 발생하는 것으로 평가한다. 특히, 암반사면 평면파괴는 절리면의 방향성에 대하여 일반적으로 '활동가능성이 있는 면의 주향과 절취사면의 주향의 차이가 약 20$^{\circ}$ 이상일 경우에는 발생하지 않는 것으로 알려져 있고 설계되고 있다. 그러나, 이러한 안정조건을 만족한 경우라도 사면의 붕괴가 빈번히 발생하고 있는 실정이다. 따라서, 본 논문에서는 이러한 안정된 사면조건에도 불구하고 현장 지형여건상 붕괴가 발생한 사례를 중심으로 국내 암반사면의 평면파괴조건을 제시하였다.

• 터널과지하공간
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• 제16권2호
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• pp.146-155
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• 2006

연구지역은 고속도로 신설구간에 형성된 대절토 무한사면으로 불연속면을 따라 사면파괴활동이 시작되었다. 보강은 락앵커 공법을 시공하여 상부구간 안정화를 시도하였다. 그러나 앵커보강 하부구간에 대규모 붕괴가 추가 발생하였고 이후 2차례 더 진행되었다. 붕괴원인을 분석하기 위하여 시료를 채취하고 직접전단시험을 실시하여 잔류전단강도를 확인하였다. 그리고 붕괴지반의 앵커력 확보를 화인하기 위하여 앵커인발시험을 실시하고 앵커설계에 반영하였다. 앵커는 붕괴면의 굴곡이 심하고 연경의 변화가 심한 지반상태를 고려하여 계단식 옹벽과 조합하여 앵커력을 확보하도록 하였다.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2009년도 춘계 학술발표회
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• pp.620-625
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• 2009

The seismic slope stability is most often evaluated by the pseudo-static limit analysis, in which the earthquake loading is simplified as static inertial loads acting in horizontal and/or vertical directions. The transient loading is represented by constant acceleration via the pseudostatic coefficients. The result of a pseudostatic analysis is governed by the selection of the value of the pseudostatic coefficient. However, selection of the value is very difficult and often done in an ad hoc manner without a sound physical reasoning. In addition, the maximum acceleration is commonly estimated from the design guideline, which cannot accurately estimate the dynamic response of a slope. There is a need to perform a 2D dynamic analysis to properly define the dynamic response characteristics. This paper develops the modified one-dimensional seismic site response analysis. The modified site response analysis adjusts the density of the layers to simulate the change in mass and weight of the layers of the slope with depth. Multiple analyses are performed at various locations within the slope to estimate the change in seismic response of the slope. The calculated peak acceleration profiles with depth from the developed procedure are compared to those by the two-dimensional analyses. Comparisons show that the two methods result in remarkable match.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2000년도 사면안정 학술발표회
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• pp.213-220
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• 2000

Numerical modeling of cut slope has some limits in simulating the real slopes. In the case of 2D analysis of slope stability, it is assumed that slope is simply straight even when it is concave or convex in plan view. In this study, 3D analysis in curved shape slopes has been conducted for the comparison with 2D analysis in terms of failure mode and factor of safety. For this, 3D analysis by FLAC3D was compared with 2D analysis in plane strain condition and axi-symmetric model condition by FLAC. It was also observed how safety factors of slopes were affected by the variation of the tensile strength and cohesion, which are important variables to decide whether the slope fails or not. 2D analysis of concave slopes under plane strain condition showed much smaller safety factors by 16-40 % errors depending on the radius of curvature of slopes, compared to the more realistic values from 3D analysis. In case of convex slopes, the lower values by 7-10 % has been reported. 2D analysis of axi-symmetric model showed also smaller safety factors by 6-10 % and by 2-4 %, in case of concave and convex slopes, respectively. Such results are expected to contribute to the better understanding of failure process and could be applied for improved design of slopes.

• Earthquakes and Structures
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• 제21권6호
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• pp.601-612
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• 2021

The paper concerns the selection of a design accelerograms used for the slope stability assessment under earthquake excitation. The aim is to experimentally verify the Arias Intensity as an indicator of the excitation threat to the slope stability. A simple dynamic system consisting of a rigid block on a rigid inclined plane subjected to horizontal excitation is adopted as a slope model. Strong ground motions recorded during earthquakes are reproduced on a shaking table. The permanent displacement of the block serves as a slope stability indicator. Original research stand allows us to analyse not only the relative displacement but also the acceleration time history of the block. The experiments demonstrate that the Arias Intensity of the accelerogram is a good indicator of excitation threat to the stability of the slope. The numerical analyses conducted using the experimentally verified extended Newmark's method indicate that both the Arias Intensity and the peak velocity of the excitation are good indicators of the impact of dynamic excitation on the dam's stability. The selection can be refined using complementary information, which is the dominant frequency and duration of the strong motion phase of the excitation, respectively.

• 한국산학기술학회논문지
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• 제15권8호
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• pp.5342-5348
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• 2014

설계기준에 제시되어 있는 사면 표준경사의 적용한계와 소단폭이 사면의 안정성에 미치는 영향을 살펴보고자 사면안정해석을 수행하고 그 결과를 비교분석해보았다. 해석에서 고려한 기본 성토단면 및 절토단면과 유사한 조건의 단면에 대해서는 설계기준에 제시된 표준경사를 적용하더라도 문제는 없을 것으로 보이며 지하수가 있는 상태에서는 지하수위를 고려한 별도의 사면안정해석을 수행되어야 할 것으로 판단된다. 소단을 두는 경우와 그와 동등한 해석단면적을 갖도록 경사를 완화한 경우에 대한 사면 안전율을 비교해 볼 때 소단을 두는 경우의 안전율이 경사를 완화한 경우보다 크게 계산되었으며 소단폭이 커질수록 안전율의 차이 또한 컸다. 해석에서 고려한 모든 단면에 대하여 기본 검토단면에 대한 사면안전율 증분값은 소단폭에 대체적으로 비례하는 결과를 보였는데 소단폭이 7m인 성토사면과 절토사면의 경우 안전율 증분값은 각각 34.5%와 48% 정도였다.