• 제목/요약/키워드: Earth-Anchor Method

검색결과 41건 처리시간 0.026초

시공중 계측을 통한 어스앵커 축력변화 특성사례 연구 (Case Study of Earth Anchor Axial Force Change Characteristic through Monitoring during Construction Period)

  • 김성욱;한병원
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 2004년도 춘계학술발표회
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    • pp.285-292
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    • 2004
  • Earth Anchor method as a supporting system is widely used in the large scale deep excavation of urban areas or slope excavation project. Considering the application frequency of that method and catastrophe of that method under unproper construction management, we can find out many problems relevant to the domestic design and construction management of earth anchor method. When we encounter the cases of rapid increments and various decrements in earth anchor axial forces, considering the characteristic of earth anchor method, it is an essential point to catch the reasons and to prepare countermeasures. This article introduces two actual monitoring examples based on the close analyses of measured data in a typical large scale deep excavation project and slope excavation project. One is a rapidly increasing case of earth anchor axial forces with the continuous advance of incremental deformation in a geological layer interface. And another is a decreasing case of earth anchor axial forces with the construction conditions. The effort of this article aims to improve and develop the technique of design and construction in the coming projects having similar ground condition and supporting method.

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기초근가와 기존근가의 하중에 따른 변위 비교분석 (A Comparative Analysis of Displacement Measurement of the Earth Surface by Load for Root Anchor Block and Rectangle Anchor Block)

  • 문성원;김점식;김도영;박용범
    • 전기학회논문지
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    • 제62권6호
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    • pp.863-869
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    • 2013
  • In this paper, we compared and analyzed for safety 1.2m rectangular anchor block and arch-type root anchor block. First, numerical analysis was performed three-dimensional nonlinear method by numerical model test using finite element analysis program "Visual FEA". Then, measure displacement of the surface of the earth after construct each anchor block at 14M electric pole and increase loads through field verification tests for safety evaluation.

앵커로 지지되는 흙막이 벽의 겉보기 토압 (Apparent Earth Pressure on Anchored Walls)

  • 김낙경
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 2001년도 봄 학술발표회 논문집
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    • pp.387-394
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    • 2001
  • An apparent earth pressure envelope for anchored walls proposed by FHWA was compared with Terzaghi & Peck's earth pressure envelope. The anchor design load, the maximum bending moment and the penetration depth were calculated by a simple beam analogy method for each type of envelope.

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근접 깊은 굴착에서 천공장비에 의한 지반교란 특성 사례 연구 (Case Study of Ground Disturbance Characteristic due to Drilling Machine in Adjacent Deep Excavation)

  • 김성욱;한병원
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 2003년도 봄 학술발표회 논문집
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    • pp.77-84
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    • 2003
  • Deep excavations in the urban areas have been frequently going on in large scale. Soil-nailing and Earth-anchor supporting methods are generally used in deep excavation. These construction methods cause ground disturbances during drilling process, and damages of adjacent structures and ground due to the differential settlement throughout construction period, and unexpected behaviors of supporting system according to the characteristics of drilling machine and ground condition. This article introduces two actual examples of adjacent deep excavation for the construction of university buildings in granitic Seoul area. The important results of construction and measurements obtained using Crawler drilling machine for Soil-nailing and Earth-anchor supporting methods are summarized. And some suggestions are given to improve and develop the technique of design and construction in the deep excavation projects having similar ground condition and supporting method.

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NATE터널의 갱문 가시설 배후 균열에 따른 조치 및 보강사례

  • 길호언;김진흥;유재성;차복남
    • 기술발표회
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    • 통권2006호
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    • pp.342-355
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    • 2006
  • The Tunnel portal is designed on temporary support system which is composed by 28m height H-Pile method and Ground Anchor method. The tunnel has excavated about 30m from the portal, but some deformation is found on the surface ground just above the tunnel face. It was investigated very carefully to find out the causes of deformation. By the observation and study, two main causes of deformation are found out. The one is earth pressure increase compared with classical earth pressure theory. That was due to the direction of ground rock mass's discontinuities. It causes the increase of earth pressure that are activated by the direction of discontinuity. The other one is that present design method neglect the transferred force by removal of temporary support members and ground anchor within the tunnel contour line as the tunnel excavation proceeds As the result of removals of the member and anchor, some force transferred from removed systems to remaining supporting systems. In designing the portal support systems, lt must be considered the discontiunity of ground mass and the transfered force due to excation.

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압축헝 앵커의 설계법 개발 (Development of Design Method of Compression(SSC) Anchor)

  • 임종철;홍석우;이태형;이외득
    • 한국지반공학회논문집
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    • 제15권1호
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    • pp.63-78
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    • 1999
  • 압축형 앵커의 설계를 위해서는 세가지의 조건이 고려되어져야 한다. 그 첫째가 주면마찰저항력이고, 둘째가 강선의 인장강도이고, 셋째가 그라우트의 압축강도이다. 특히, 세가지 조건 중에서도 그라우트의 압축강도는 압축형 앵커의 인발력 산정에 있어서 가장 중요한 매개변수가 된다. 압축형 앵커가 지중에서 인발될 때, 그라우트의 압축강도는 지반 구속압에 의해 증가하게 된다. 이 지반 구속압은 정지 토압에 의한 구속압과 "포아송 효과"라고 부르는 횡방향 팽창에 의해 증가되는 구속압으로 이루어져 있다. 본 논문에서는 압축형 앵커인 SSC 앵커의 내하체 압축시험을 통해 앵커 설계법을 제안하고, 이 설계법을 사용하여 앵커의 인발저항력을 계산하는 컴퓨터 프로그램을 개발하였다.그램을 개발하였다.

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그라운드 앵커공법용 아치형 앵커브라켓의 구조해석 (Structural Analysis of Arch Anchor Brackets in Ground Anchor Construction)

  • 김재열;김영호
    • 한국공간구조학회논문집
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    • 제14권1호
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    • pp.69-76
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    • 2014
  • When we excavate an underground to build basement, the ground anchors are needed to prevent collapse of neighboring ground, subsidence and movement. Ground anchor construction required shore sheet piles, wales and struts as to maintain secure excavation. Existing box-type bracket using head part of ground anchor can not be possibly adjustable to the boring angle because the brackets are manufactured with unified angle in a factory. Also, box-type brackets have imperfection and instability caused by inequable force. In this study, a new bracket system is proposed. The bracket's side plate is reinforced and the angle of boring can be controlled. To investigate the structural performance of presented brackets, FEM analysis has been performed by using ANSYS commercial program. As a result, this bracket shows sufficient stability for all angle case and the strength is increased about 24% than existing bracket.

석축구조물 및 배면지반의 안정성 검토사례연구 (A Case Study on the Stability Analysis for Masonry Retaining Walls and Backfill)

  • 천병식;여유현;김경민
    • 한국구조물진단유지관리공학회 논문집
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    • 제5권1호
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    • pp.149-160
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    • 2001
  • In this paper, the stability analyses were performed for masonry retaining wallls in Seoul subway System. This masonry retaining wallls were reinforced with earth anchor system for the construction, but it was removed after construction. Therefore, the stability of masonry retaining wallls should be checked after the earth anchors removed. For stability analysis of masonry retaining wallls. FDM analysis(FLAC Ver.3.3) and slope stability analysis (SLOPE/W) were performed applying the test results from laboratory and field tests(Schmidt hammer test, cack examination). As conclusion, the tension force of earth anchors should be kept, therefore, substitutional method was required in order to keep the tension force of earth anchor system.

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