• Title/Summary/Keyword: earth-anchor

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Simplified Formula for Design of Fixed Earth Supported Sheet-Pile Wall in Sand (사질토 지반 앵커식 고정지지 널말뚝 설계용 간편식)

  • Yang, Woo-Shik;Kim, Khi-Woong
    • Magazine of the Korean Society of Agricultural Engineers
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    • v.40 no.6
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    • pp.89-94
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    • 1998
  • Stock(1992) had developed the graph for solving the penetration depth, tieforce of anchor and maximum bending moment of sheet-pile wall for cantilever and free earth supported anchored wall. Kim(1995) had developed graph for design of fixed earth supported anchored wall. In this paper, the simplified formulas for calculating the penetration depth, tieforce of anchor and maximum bending moment of sheet-pile wall was developed for fixed earth supported anchored wall in sand. The developed formulas may be helpful for design or sheet pile wall.

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

  • Chun, Byung-Sik;Yeoh, Yoo-Hyeon;Kim, Kyung-Min
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.5 no.1
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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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Earth Pressuroes of Tieback Walls in Sand (사질토에 시공된 앵커토류벽의 토압분포에 관한 연구)

  • 김낙경
    • Geotechnical Engineering
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    • v.14 no.5
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    • pp.17-28
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    • 1998
  • The design of a ground anchor wall calculating the design anchor force and anchored walls depends primarily on the earth pressure acting on anchored w deflection of the wall, the wall stiffness, distribution exists for anchored walls. In the apparent earth pressure envelope design of anchored walls. In this study, full scale anchored w pressure distribution was obtained from function. Earth pressures obtained from pressure and with the apparent earth pre the anchored wall in sand. It is conclude is appropriate for the anchored wall design.

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A Study on the Application of Lateral Earth Pressure to Earth Retaining Wall Considering Ground Characteristics in Jeju II - Case of Earth Anchor Construction - (제주 지역의 지반 특성을 고려한 흙막이벽의 측방토압 적용에 관한 연구 II -어스앵커 공법 시공 사례-)

  • Do-Hyeong Kim;Dong-Wook Lee;Seung-Hyun Kim;Kwon-Moon Ko
    • Journal of the Korean Geosynthetics Society
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    • v.22 no.2
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    • pp.85-92
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    • 2023
  • This paper describes the comparative results of measured and predicted values for the horizontal displacement of earth retaining wall based on two field cases, in order to evaluate the application of lateral earth pressure to earth retaining wall supported by earth anchor in Jeju. The prediction of lateral earth pressure acting on the earth retaining wall was performed by elasto-plastic analysis using Rankine earth pressure, Hong & Yun lateral earth pressure, Terzaghi & Peck modified lateral earth pressure, and Tschebotarioff lateral earth pressure. As a result, the predicted value of the maximum horizontal displacement for site A was about 10 to 12 times greater than the measured value, and in the case of site B, the predicted value was evaluated as about 9 to 12 times greater than the measured value. That is, both sites showed a similar increase rate in the maximum horizontal displacement by the predicted value compared to the measured value. In all field construction cases, the maximum horizontal displacement by measured values occurred in the sedimentary layer, soft rock layer, and clinker layer, and the horizontal displacement distribution was shown in a trapezoidal shape. The maximum horizontal displacement by the predicted value occurred around the clinker layer, and the horizontal displacement distribution was elliptical. In the ground with a clinker layer, the measured value showed a very different horizontal displacement tendency from the predicted value, because the clinker layer exists in the form of a rock layer and continuous layer. In other words, it is unreasonable to apply the existing prediction method, which is overestimated, because the characteristics of the earth pressure distribution in Jeju show a tendency to be quite different from the predicted earth pressure distribution. Therefore, it is necessary to conduct a research on the lateral earth pressure in the realistic Jeju that can secure more economic efficiency.

Lateral Earth Pressures Acting on Anchored Retention Walls for Underground Excavation (지하굴착시 앵커지지 흙막이벽에 작용하는 측방토압)

  • 홍원표;윤중만
    • Geotechnical Engineering
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    • v.11 no.1
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    • pp.63-78
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    • 1995
  • Recently, in order to utilize more effectively underground space, deep excavations have been performed on building or subway construction in urban areas. In such excavations, anchors have been used to support the excavation retaining walls because the anchored excavation could provide wide working space for underground construction. The purpose of this paper is to establish empirical equations to be able to estimate the earth pressures acting on anchored excavation retention walls, based on the investigation of field measuring results, which were obtained from twenty seven building construction sites. The prestressed anchor force was measured by load cells which were attached to the anchor head, while the horizontal displacement of excavation walls were measured by inclinometers which were installed right'behind the retention walls. The lateral earth pressures acting on the anchored retention walls, which were estimated from both the measured anchor forces and the horizontal displacement of the walls, showed a trapezoidal distribution. There was some difference between the measured earth pressures acting on the anchored retention walls and the empirical earth pressures given by several empirical equations. Thus, the lateral earth pressures acting on anchored retention walls would be estimated by these empirical equations with some modifications.

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NATE터널의 갱문 가시설 배후 균열에 따른 조치 및 보강사례

  • Kil, Ho-Un;Kim, Jin-Hong;Yoo, Jai-Sung;Cha, Bok-Nam
    • 기술발표회
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    • s.2006
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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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Development of Design Method of Compression(SSC) Anchor (압축헝 앵커의 설계법 개발)

  • 임종철;홍석우;이태형;이외득
    • Journal of the Korean Geotechnical Society
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    • v.15 no.1
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    • pp.63-78
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    • 1999
  • For the design of compression anchor, three things should be considered. The first is a resistance force by skin friction, the second is a tension strength of tendon, and the third is a compressive strength of grout. Especially, compressive strength of grout is the most important design parameter of compression anchor. When compression anchor is pulled out from the ground, the compressive strength of grout increases by confining pressure of ground($\sigma_{tg$). Here, $\sigma_{tg$ is the confining pressure which is produced by earth pressure at rest and by lateral expansion of grout. We call this phenomenon of increase of confining pressure "poisson effect". In this paper, the design method of compression anchor called SSC anchor and the computer program for the design are developed through compression tests of anchor body grout.ody grout.

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A Study on the Behaviour of Jacket Anchor (자켓앵커 거동특성에 관한 연구)

  • Kim, Dong-Hee;Kim, In-Chul;Kong, Hyun-Seok;Lee, Woo-Jin
    • Journal of the Korean Geotechnical Society
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    • v.24 no.8
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    • pp.89-97
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    • 2008
  • A series of field tests were performed to investigate the behavior of jacket anchor and to evaluate the ultimate bond stress of jacket anchor. From twelve sets of field tests on the jacket anchor and general type ground anchor, it was observed that the pullout resistance of jacket anchor is significantly larger than that of the ground anchor and that the plastic deformation of jacket anchor is significantly smaller than that of general ground anchor at the same loading cycle. Especially in gravel layers, the jacket anchor provides more than 250% increase in ultimate resistance and more than 600% reduction in plastic deformation, compared with the general ground anchor. Finally, the relationship between the injection pressure and overburden pressure is proposed to determine the optimum injection pressure, based on additional field test results.

Failure Modes of Vertical Ground Anchor in Plane Strain (평면변형률 상태에 있는 연직지반앵커의 파괴모-드)

  • Im, Jong-Cheol;;Park, Seong-Jae
    • Geotechnical Engineering
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    • v.6 no.1
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    • pp.43-58
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    • 1990
  • In order to get ultimate pullout resistance of ground anchor, the position of failure surface, normal stress and friction angle on the failure surface should be known. In this study, the position of failure surface is obtained by observing deformation of ground around anchor, and stresses on the anchor surface are analyzed by measuring normal and shear stresses on the anchor surface through model anchor test in plane strain. In addition, the relationship between lateral earth pressure and the position of failure surface is analyzed and the formula for calculating ultimate pullout resistance of anchor is proposed by using non-dimensional coefficient of ultimate pullout resistance.

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