• 제목/요약/키워드: soil thickness

검색결과 565건 처리시간 0.026초

풍화토-그라우트 인터페이스 전단 거동 특성에 대한 실험적 연구 (Experimental Study on the Residual Soil-Grout Interface-shearing Behavior )

  • 신규범;정충기;김인현;조범희
    • 한국지반공학회논문집
    • /
    • 제39권4호
    • /
    • pp.19-29
    • /
    • 2023
  • 본 연구에는 지반-그라우트 인터페이스 거동을 평가하기 위한 직접전단시험 장비를 제작하였으며, 제작된 시험 장비를 통해 풍화토, 풍화토-그라우트 두 종류의 시료에 대해 직접전단시험을 수행하였다. 전단응력-슬립 곡선 평가 결과 풍화토-그라우트의 잔류 전단 강도는 단일 풍화토의 잔류 전단 강도와 유사한 값을 나타냈으며, 풍화토-그라우트 인터페이스의 한계 상태 거동은 풍화토에 의해 결정된다는 것을 확인했다. 그러나, 최대 전단 강도의 경우 풍화토-그라우트 인터페이스에서 매우 크게 증가하는 것으로 나타났다. 최대 전단 강도의 증가율은 느슨한 지반에서 더 크게 발생하는 것으로 나타났으며, 이는 풍화토 입자와 그라우트 입자가 섞여 있는 인터페이스 레이어의 두께가 증가했기 때문으로 보인다.

폐기물 매립지의 부직포 포설시 UV 영향에 대한 평가 (The Evaluation of Geotextiles by Ultraviolet(UV) Effect during the Landfill Construction)

  • 고재학;이재영
    • 한국지하수토양환경학회:학술대회논문집
    • /
    • 한국지하수토양환경학회 1998년도 공동 심포지엄 및 추계학술발표회
    • /
    • pp.206-215
    • /
    • 1998
  • Using of geosynthetics with linear materials(sand, gravel, clay soil) is rapidly increased in landfill. With geosynthetics, geotextiles often expose to solar radiation(Ultraviolet) on long terms during the installation. In this paper, the results will represent the strength retention rate and tensile retention rate of geotextiles between outdoor exposed and protected by 15cm thickness of soil. As a result of cumulating solar radiation in geotextiles was increased, the strength retentions rate of P.P(500g/$m^2$), P.P(700g/$m^2$) and P.P(1000g/$m^2$) were decreased and the lower weight of unit area of geotextiles, the faster decrease of strength retention rate. P.E.T(600g/$m^2$) was showed a distinctive trend that the strength retention rate increased. The tensile retention rate of tested geotextiles was decreased during the simulation. However, the strength and tensile retention rate of geotextiles covered by soil had changed insignificantly. Therefore, it can surmise that the soil covering will help geotextiles to be protected from UV effecting

  • PDF

중금속 오염 농경지 토양의 복원을 위한 토량개량법의 효과 비교 (A Comparison on the Effect of Soil Improvement Methods for the Remediation of Heavy Metal contaminated Farm Land Soil near Abandoned Mines)

  • 유찬;윤성욱;강신일;진혜근
    • 한국지반공학회:학술대회논문집
    • /
    • 한국지반공학회 2010년도 춘계 학술발표회
    • /
    • pp.984-999
    • /
    • 2010
  • A long-term field demonstration experiment of selected stabilization method to reduce the heavy metal mobility in farmland soil contaminated by heavy metals around abandoned mine site was conducted. Field demonstration experiments were established on the contaminated farmland with the wooden plate(thickness=1cm) which dimension were width=200cm, Length=200cm, height=80cm and filled with treated soil, which was mixed with lime stone and steel refining slag except on control plot. Soil samples in the plots were collected and analyzed during the experiment period(2008. 2~2008. 8) after the installation of the plots. Field demonstration experiments results showed that the application ratio of lime stone 5% was effective for immobilizing heavy metal components in contaminated farmland soil.

  • PDF

Application of a weight-of-evidence model to landslide susceptibility analysis Boeun, Korea

  • Moung-Jin, Lee;Yu, Young-Tae
    • 한국GIS학회:학술대회논문집
    • /
    • 한국GIS학회 2003년도 공동 춘계학술대회 논문집
    • /
    • pp.65-70
    • /
    • 2003
  • The weight-of-evidence model one of the Bayesian probability model was applied to the task of evaluating landslide susceptibility using GIS. Using the location of the landslides and spatial database such as topography, soil, forest, geology, land use and lineament, the weight-of-evidence model was applied to calculate each factor's rating at Boun area in Korea where suffered substantial landslide damage fellowing heavy rain in 1998, The factors are slope, aspect and curvature from the topographic database, soil texture, soil material, soil drainage, soil effective thickness, and topographic type from the soil database, forest type, timber diameter, timber age and forest density from the forest map, lithology from the geological database, land use from Landsat TM satellite image and lineament from IRS satellite image. Tests of conditional independence were performed for the selection of the factors, allowing the 43 combinations of factors to be analyzed. For the analysis, the contrast value, W$\^$+/and W$\^$-/, as each factor's rating, were overlaid to map laudslide susceptibility. The results of the analysis were validated using the observed landslide locations, and among the combinations, the combination of slope, curvature, topographic, timber diameter, geology and lineament show the best results. The results can be used for hazard prevention and planning land use and construction

  • PDF

유류오염지역 정화를 위한 슬러핑과 미생물증진법의 효율평가에 관한 현장 적용성 연구 (A Field Study on the Evaluation of Slurping and Bioaugmentation Effect in Petroleum Contaminated Area)

  • 박응렬;이광렬;서창일;조장환
    • 한국지하수토양환경학회지:지하수토양환경
    • /
    • 제17권3호
    • /
    • pp.32-38
    • /
    • 2012
  • This study was conducted to evaluate the slurping process affecting the variation of free product and VOCs concentration and the bioaugmentation effect on bioremediation process. Free products and soil gas were extracted from 30 extraction wells installed in a petroleum contaminated area. The extraction system was operated for 10 hours per day with 1 hour on-and-off mode. The thickness of free product in extraction well was decreased from 11.7 cm to 4.5 cm and the VOCs concentration was increased from 10.37 ppm to 30.78 ppm during the operation period. After the slurping process for 2 months, contaminated soil was treated with bioremediation process in 2 cells, $15{\times}40$ m, biologically enhanced with adjusting oxygen, moisture and nutrients concentration. Total 1,400 L of microbial inoculant, Naturesys. (Dong Myung Ent. Co.) was added to the pile B, which has an outstanding ability for degrading petroleum hydrocarbons. The results showed that bioremediaton effect in soil with the microorganisms solution is 33% higher than that in soil with only residual bacteria.

목본식물의 형성층 전기저항에 의한 영구위조점 예측에 관한 연구 (A Study on the Prediction of the Permanent Wilting Point in Woody Plant by Cambial Electrical Resistance)

  • 김민수
    • 한국조경학회지
    • /
    • 제22권4호
    • /
    • pp.75-80
    • /
    • 1995
  • It is important to estimate the possibility of recovery in physiologically damaged woody plant. It is suggested that C.E.R(cambial electrical resistance) might be a useful method to predict the permanent wilting point. D/A and A/D converter can be used to measure the C.E.R and it took only 10-20 msec for a measurement and the values were stable during this study. A computer could be used for the continual measurement of C.E.R. There were very big daily changes of C.E.R. was changed according to the changes of indoor temperature, but the phase was slightly different. It is reasoned that daily changes in C.E.R. is induced by the changes of water potential and cambial thickness. It was difficult to detect the changes of C.E.R. caused by changes in soil moisture under high soil water potential. Under low soil water potential, the changes in soil moisture under high soil water potential. Under low soil water potential, the changes of C.E.R. can be detected. After wilting, C.E.R. is increased very rapidly. When C.E.R. is not decreased by watering, it will be permanent wilting point. But it takes several days to confirm the permanent wilting point. To predict the possibility of recovery from wilting, the values of C.E.R. have no meaning. But the changes of C.E.R. are significant. Therefore we can predict the permant wilting point in woody plant by monitoring the change of C.E.R. by the computer.

  • PDF

확률론적 침투해석을 통한 무한사면 파괴의 특성 연구 (Study on the Characteristics of Infinite Slope Failures by Probabilistic Seepage Analysis)

  • 조성은
    • 한국지반공학회논문집
    • /
    • 제30권10호
    • /
    • pp.5-18
    • /
    • 2014
  • 세계의 많은 지역이 강우에 의한 사면파괴가 취약하다. 사면파괴의 발생 메커니즘을 파악하기 위해 지금까지 다양한 방법들이 제안되어져 왔으나 현재 사용되는 방법들은 비균질한 지반분포와 수리학적 거동이 강우로 인한 사면파괴에 미치는 효과를 고려하지 못한다. 본 연구에서는 강우 시 토층의 두께에 따른 사면파괴의 발생 메커니즘을 연구하기 위하여 불투수 기반암 위에 존재하는 풍화 잔류토 사면에 대한 확률론적 사면안정 해석을 수행하였다. 불균질한 투수계수의 공간적 분포로 인한 불확실성이 강우침투에 의한 불포화 사면의 파괴에 미치는 영향을 고려하기 위하여 일차원 랜덤필드에 기초한 일련의 침투해석과 사면 안정해석을 수행하였다. 해석결과에 의하면 확률론적 해석법은 사면에 대한 강우의 침투 평가 시 투수계수의 공간적인 변동에 의하여 발생하는 다양한 파괴 패턴을 효과적으로 고려할 수 있음을 보여준다.

생육보조재 취부 공법에 의한 비탈면 녹화 식생배합의 적정성에 관한 연구 (A Study on the Seeding Mixture Improvements for the Restoration and Revegetation of the Slopes by the Thin-Layer-Soil-Media Hydroseeding Revegetation Measures)

  • 김정훈;허영진;김남춘;정용문
    • 한국환경복원기술학회지
    • /
    • 제8권2호
    • /
    • pp.90-97
    • /
    • 2005
  • This study aimed to address problems and suggest solutions in applying seed mixture design criterior of slope revegetation works according to the "Slope revegetation design and guidelines(proposed)" proposed by the Ministry of Construction and Transportation. To do this, a proper thickness of attaching soil media was identified in April experiment where the thickness and slopes varied. The results were as follows. In the test, the coverage rate of plot where exotic grass was not sowed increased with time and was 79.3% after three months of seeding, which indicated less risk of soil erosion. When applying the provisional standards of the plant mix proposed by the Ministry of Construction and Transportation, tree seeds and native plants were found ill in the early stage in all test lands due to exotic grass. This was because exotic grass which grew well in the early stage, could grow densely, so it might hamper the growth of other plants. When slope revegetation were planted and goals were set for herb, shrub and tree dominant mixture types, it was required to shift focus toward nursing up native plants first rather than early plantation of exotic grass.

울산지역 제3기 정자분지의 도로사면 지반특성 (Geotechnical Characteristics of Cut Slope in Tertiary Jungja Bain, Ulsan area)

  • 김승현;구호본;이정엽;이종현;박성규;김관영
    • 한국지반공학회:학술대회논문집
    • /
    • 한국지반공학회 2005년도 춘계 학술발표회 논문집
    • /
    • pp.107-112
    • /
    • 2005
  • Road is built continuously along with development of industry and cut slope is happened necessarily in road construction. Geoengineers are executing cut slope stability analysis considering various cut slope condition such as topography, geology, hydraulic condition and so on. The Tertiary Jungja Basin is located in the southeastern coastal area of the Korea Peninsula. Jungja Basin area is created by geotectonic movement of the plate after Early Miocene epoch. The northwestern and southwestern boundary of the basin is fault zone. The Basement rock is hornfels (Ulsan Formation). Basin-fills consist of extrusive volcanic rock(Tangsa Andesites), unconsolidated fluviatile conglomerate(Kangdong Formation) and shallow brackish-water sandstone(Sinhyun Formation). The characteristics of cut slopes in this area is different with cut slopes in the other site. Soil layers in this area is unconsolidated sediments and is not formed the weathering and erosion of the rock. So, the depth of soil layer is very thick. Faults of this area are northwest-southeast and northeast-southwest direction. Expandible clay mineral as smectite, chlorite et al. detected from fault gouge using XRD. Therefore, Jungja Basin area must consider the characteristics of the faults and soil layers thickness necessarily cut slopes stability analysis.

  • PDF

정상류하 침투·이류 분산 해석을 이용한 폐기물 해상최종처리장 차수시스템의 최적 성능 평가 (Evaluation of Optimal Performance of Hydraulic Barriers in Offshore Landfill using Seepage-Advection-Dispersion Analysis under Steady State Flow)

  • 황웅기;오명학;김태형;김향은
    • 한국해안·해양공학회논문집
    • /
    • 제30권2호
    • /
    • pp.61-68
    • /
    • 2018
  • 본 연구는 정상류 조건에서 폐기물 해상최종처리장에서의 오염원의 누출 방지에 필요한 최적의 최소기준을 제안하기 위하여 각각 바닥 및 연직 차수시스템의 기본적인 차수공에 대하여 침투 이류 분산해석을 수행하였다. 연구 결과 바닥 차수시스템의 최소기준으로 투수계수 $1{\times}10^{-6}cm/s$ 이하인 불투수성 지층이 두께 500 cm 이상이거나 이와 동등한 차수효과를 가진 차수시스템이어야 한다. 연직 차수시스템의 최소기준으로 투수계수 $1{\times}10^{-6}cm/s$ 이하인 두께 50 cm 이상이거나 이와 동등한 차수효과를 가진 차수시스템을 설치하여야 한다. 또한, 연직 차수시스템은 바닥 차수시스템과 일체가 되어 차수기능을 발휘하도록 충분한 근입깊이가 필요하다.