• 제목, 요약, 키워드: Ground investigation

검색결과 910건 처리시간 0.044초

수치해석수법과 지질공학적 분석을 통한 NATM터널의 붕괴메커니즘에 관한 연구 (Failure Mechanism of NATM tunneling using Computational Methods and Geology Investigation)

  • 이재호;김영수;최해준;정윤영;김광일;임홍래
    • 한국지반공학회:학술대회논문집
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    • pp.742-753
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    • 2008
  • Currently an increasing number of urban tunnels with small overburden are excavated according to the principle of the New Austrian Tunneling Method (NATM). Therefore, a possibility of a tunnel collapse during excavation is getting higher in a proportionate manner. This paper will analyze causes the failure mechanism of a shallow NATM tunnel for different geological conditions, ground-water and invert solutions by investigation typical collapse site during tunnel construction. In this paper, this analysis performed two phase, firstly, the field investigation considering displacement measurement, ground-water level, geological characteristic, secondly, the numerical simulation considering the exist of invert construction and the effect of ground-water. It has been found that environmental factors such as state of underground water or construction sequences could influence failure mechanism of a shallow tunnel.

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대심도 암반의 터널 설계를 위한 지반 조사와 특성화 (Ground Investigation and Characterization for Deep Tunnel Design)

  • 윤운상;최재원;박정훈;송국환;김영근
    • 한국지반공학회:학술대회논문집
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    • pp.584-590
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    • 2009
  • One of the critical design problems involved in deep tunnelling in brittle rock, is the creation of surface spalling damage and breakouts. If weak fault zone is developed in deep tunnel, squeezing problem is added to the problems. According to the results of ground investigation in the study area, hard granitic rockmass and distinguished high angle fault zone are distributed on the tunnel level over 400m depth. To analyse the probability of brittle failure and squeezing, ground characterization with special lab. and field test were carried out. By the results, probability of brittle failures like spalling and rock burst is very low. But squeezing may be probable, if weak fault zone observed surface and drill core is extended to designed tunnel level.

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지하굴착시 지하수저하에 따른 지반침하 - 수치해석 연구 (Ground Deformation involving drawdown of the water table in deep excavation - Numerical Investigation)

  • 최고니;유충식
    • 한국지반공학회:학술대회논문집
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    • pp.13-20
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    • 2010
  • This paper presents the results of a numerical investigation on the ground deformation in deep excavation with emphasis on the groundwater lowering. Using the stress-pore pressure coupled analysis Consideration to the effect of ground excavation and groundwater interaction were carried out and a series of two-dimensional finite element model was employed to perform a parametric study on a wide range of soil profile and initial ground water table condition.

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Moment resisting steel frames under repeated earthquakes

  • Loulelis, D.;Hatzigeorgiou, G.D.;Beskos, D.E.
    • Earthquakes and Structures
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    • v.3 no.3_4
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    • pp.231-248
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    • 2012
  • In this study, a systematic investigation is carried out on the seismic behaviour of plane moment resisting steel frames (MRF) to repeated strong ground motions. Such a sequence of earthquakes results in a significant damage accumulation in a structure because any rehabilitation action between any two successive seismic motions cannot be practically materialised due to lack of time. In this work, thirty-six MRF which have been designed for seismic and vertical loads according to European codes are first subjected to five real seismic sequences which are recorded at the same station, in the same direction and in a short period of time, up to three days. Furthermore, the examined frames are also subjected to sixty artificial seismic sequences. This investigation shows that the sequences of ground motions have a significant effect on the response and, hence, on the design of MRF. Additionally, it is concluded that ductility demands, behaviour factor and seismic damage of the repeated ground motions can be satisfactorily estimated using appropriate combinations of the corresponding demands of single ground motions.

Study on seismic behavior and seismic design methods in transverse direction of shield tunnels

  • He, Chuan;Koizumi, Atsushi
    • Structural Engineering and Mechanics
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    • v.11 no.6
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    • pp.651-662
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    • 2001
  • In order to investigate the seismic behavior and seismic design methods in the transverse direction of a shield tunnel, a series of model shaking table tests and a two-dimensional finite element dynamic analysis on the tests are carried out. Two kinds of static analytical methods based on ground-tunnel composite finite element model and beam-spring element model are proposed, and the validity of the static analyses is verified by model shaking table tests. The investigation concerns the dynamic response behavior of a tunnel and the ground, the interaction between the tunnel and ground, and an evaluation of different seismic design methods. Results of the investigation indicate that the shield tunnel follows the surrounding ground in displacement and dynamic characteristics in the transverse direction; also, the static analytical methods proposed by the authors can be used directly as the seismic design methods in the transverse direction of a shield tunnel.

폐기물매립지 주변 침출수 누출 및 지반오염 조사연구 (Investigation of ground contamination and leachate leakage around waste landfill)

  • 정하익;김상근;정길수;이용수;조동행;강상구;지상근
    • 한국지반공학회:학술대회논문집
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    • pp.309-312
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    • 1999
  • In recent years there has been a steady increase in geoenvironmental engineering projects where geotechnical engineering has been combined with environmental concerns. Many of these projects involve some investigation on contaminant and leachate flume in the ground and landfill. In this study, investigation on leachate around the waste landfill was carried out to detect the leaked and contaminated area. Many techniques such as geophysical, drilling and sampling method were applied. As a result of this study, the concentration of leachate and the point of leachate leaking around landfill were found out, and countermeasures for cut-off of leachate flow from landfill were investigated.

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Investigation of effectiveness of double concave friction pendulum bearings

  • Ates, Sevket
    • Computers and Concrete
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    • v.9 no.3
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    • pp.195-213
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    • 2012
  • This paper presents the investigation of the stochastic responses of seismically isolated bridges subjected to spatially varying earthquake ground motions including incoherence, wave-passage and site-response effects. The incoherence effect is examined by considering Harichandran and Vanmarcke coherency model. The effect of the wave-passage is dealt with various wave velocities in the response analysis. Homogeneous firm, medium and soft soil conditions are selected for considering the site-response effect where the bridge supports are constructed. The ground motion is described by filtered white noise and applied to each support points. For seismic isolation of the bridge, single and double concave friction pendulum bearings are used. Due to presence of friction on the concave surfaces of the isolation systems, the equation of motion of is non-linear. The non-linear equation of motion is solved by using equivalent linearization technique of non-linear stochastic analyses. Solutions obtained from the stochastic analyses of non-isolated and isolated bridges to spatially varying earthquake ground motions compared with each other for the special cases of the ground motion model. It is concluded that friction pendulum systems having single and double concave surfaces have important effects on the stochastic responses of bridges to spatially varying earthquake ground motions.

CCTV 및 GPR을 이용한 하수관로 결함 및 지반함몰 위험성 평가 (Analysis of Sewer Pipe Defect and Ground Subsidence Risk by Using CCTV and GPR Monitering Results)

  • 이대영
    • 한국지반신소재학회논문집
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    • v.17 no.3
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    • pp.47-55
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    • 2018
  • 도심지 지반함몰 현상은 최근 5년간 그 빈도수가 급속히 증가하고 있다. 지하공동의 발달은 지표 침하를 발생시키고 그로 인한 포장재의 취성파괴를 유발시킨다. 본 연구는 도심지 지반함몰의 주원인인 노후화된 하수관로 손상에 의한 지반침하를 예방하기 위한 평가기법 개발 기초연구 이다. 이를 위해 본 연구에서는 노후하수관로 하수관로 CCTV 조사를 통해 지반침하 발생 위험구간에 대해서 GPR 조사를 수행하였다. 하수관로 CCTV 조사와 GPR조사 결과를 통해 노후하수관로의 파손, 이음부 이탈, 토사퇴적 부위에서 지반 이상신호를 확인 할 수 있었다. GPR 조사를 통해 노후하수관로 주변 지반의 공동발생 가능성과 지반이완상태를 평가하였다. 본 연구결과를 통해 CCTV와 GPR 데이터의 결과를 이용한 상관관계 평가방법을 이용하면 하수관로 손상으로 인한 지반침하를 예방할 수 있을 것으로 판단된다.

석회석 광산 지역의 지반침하 원인 규명을 위한 현장조사와 지반 안정성 분석 사례 (A Case Study of Site Investigation and Ground Stability Analysis for Diagnosis of Subsidence Occurrence in Limestone Mine)

  • 이승중;김병렬;최성웅;오석훈
    • 터널과지하공간
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    • v.25 no.4
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    • pp.332-340
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    • 2015
  • 광산지역에서 발생하는 지반침하는 인명과 지표시설물에 막대한 피해를 초래할 우려가 있으므로 지반침하 발생지역에 대한 일련의 현장조사와 지반안정성 분석은 체계적으로 수행되어야 한다. 본 연구에서는 충청북도 청원군에 위치한 석회석 광산의 일부 지점에서 발생한 지반침하의 원인을 규명하기 위하여 현장조사와 지반안정성 분석을 수행하였다. 이를 위하여 조사지역 암반의 공학적 특성을 조사하고, 전기비저항 탐사를 통해 지표 부근 연약대의 분포양상을 파악하였으며, 이 결과들을 토대로 침하원인 규명을 위한 전산해석을 수행하였다. 해석결과, 본 광산지역에서 발생된 지반침하는 석회암층에서 발달된 용식공동에 의한 것으로 분석되었다.

콘크리트 궤도의 시공 및 유지관리를 위한 침하관리 통합 시스템의 구축 및 활용 (Development and Application of Integrated Settlement Management System for Construction and Maintenance of Concrete Railway)

  • 우상인;천성호;정충기;이일화;권오정
    • 한국철도학회:학술대회논문집
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    • pp.1196-1202
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    • 2007
  • In construction of high speed railway, the fan shape is limited to achieve reduction of required travel time and concrete railway which has structural stability and induces small maintenance cost with allowable ground settlement is recently applied. So construction of concrete railway on soft ground in which considerable ground settlement occurs increases and settlement management in soft ground section is required. Field monitoring on ground movement and integrated geotechnical information system which manages construction, design, and field monitoring data are essential for settlement management of concrete railway subgrade. Site investigation data are also required due to future repair work. Therefore in this study, integrated geotechnical information system for construction and maintenance of concrete railway is developed. The developed system consists of a database and an application program. The database contains site investigation, construction, design, and field monitoring data throughout a railway. Application program performs various functions on managing and utilizing information in the database with graphic visualization of output. And by providing integrating information with comprehensible visual displays, the applicability and effectiveness of the developed system for construction and maintenance management were confirmed.

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