• 제목/요약/키워드: anchor load

검색결과 304건 처리시간 0.029초

앵커의 위치에 따른 토류벽의 Mass 변형특성 (Mass Movement of Tieback Walls)

  • 김낙경;박종식;주준환
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 2003년도 봄 학술발표회 논문집
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    • pp.537-544
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    • 2003
  • Mass movement of anchored walls is defined and its characteristics were discussed. A beam on elasto-plastic foundation modeling of soldier pile and woodlagging tieback walls or anchored walls was developed and used in practice. However, the behavior of an anchored wall can not be predicted well, if the locations of anchor bonded zone are near the wall. Mass movement is defined as the movement of anchor bonded zone due to the excavation without the change in the anchor load. Case histories of anchored walls were analyzed and the normalized mass movement chart were developed. This mass movement chart can provide the idea how to locate anchors to minimize the deflection of the wall. The further the anchor bonded zone is located from the wall, the less the movement of the wall due to excavation occurs.

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간격유치장치를 이용한 어스앵커 인장에 관한 연구 (A Study of the Anchorage loss of Ground Anchor Using Spacing Apparatus and Spring)

  • 정상민;박영근;박무곤;김광억;이근호
    • 한국건축시공학회지
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    • 제5권4호
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    • pp.139-144
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    • 2005
  • A ground anchor system is used as a load carrying element in soil work. The conventional systems with ground anthers bring about the anchorage loss of wedges when anchors are installed for the support of soil structures. Hence we developed the new type of anchor system using both the spacing apparatus and spring (length 60mm, diameter 6mm). In this system, we tan directly check the condition of wedges and PS strands and modify the problems with the slip and anchorage of wedges under construction. For demonstrating the superiority of this system, we carried out a series of the laboratory test. Consequently, we can obtain satisfactory result (18.99$\%$ reduction to the loss of conventional systems). Moreover, the replacement of wedges is easy and simple when retensioning of strands.

풍화암에 근입된 그라운드 앵커의 인발거동 연구 (A Study on the Pullout Behavior of Ground Anchored in Weatherd Rock)

  • 박병수;정길수;전상현;유남재
    • 산업기술연구
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    • 제26권A호
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    • pp.109-117
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    • 2006
  • This study is an numerical study of predicting the behavior of anchor embedded in weathered rocks, subjected to uplift loads, about ultimate pullout capacity and the failure mechanism. Factors influencing the behavior of anchors were investigated by reviewing the data about in-situ anchor tests performing numerical modelling with changing the bondage length of anchor, diameter of anchor body and diameter of tenden, and by Correlations between those factors were evaluated to apply them to predict the behavior of anchors. As results of numerical analysis, a linear relationship between bondage length, diameter of anchor body and diameter of tenden with ultimate pullout capacity was obtained on the one hand, from the result of numerical analysis changing the Young's modulus of weathered rock, this parameter was found to inflence to load-displacement and ultimate pullout capacity within the range of 10%, which was mot so significant to affect.

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풍화암 지반에 정착된 앵커의 인발저항 특성 (Pull - out Capacity of Ground Anchor in Weathered Rock)

  • 이승환;황의석;이봉열;김학문
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 2002년도 가을 학술발표회 논문집
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    • pp.435-442
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    • 2002
  • Fluid Confirmation Tests(FCT) on 1500 ground Anchors install in weathered rock were carried out to investigate upper and lower limit of elastic elongation, frictional resistant of fixed anchor body, mobilized angle between anchor body and soil. All the measured data were analysed and compared with theoretical equations. The frictional angles of diaphragm wall and anchorage system in weathered rock showed nonlinear curve between upper and lower limit of standard elongation. The FCT results indicated that the frictional resistant angles increased with higher values of surcharge load. The quality assurance on the fixed anchor location was investigated by means of measuring elastic elongation during the FCT, and comparing these with theoretical design length, the quality of anchors in this particular site found to be above average standard. The results of this research works with provide valuable guide line on quality assurance of anchors system as well as resonable prediction of friction resistance between the fixed anchor body and the weathered rock.

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Anchor 볼트형태의 strain gauge 센서모듈설계 (Implementation of Anchor Bolt Type Strain Gauge Sensor Module)

  • 곽재민;임춘식
    • 한국정보통신학회:학술대회논문집
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    • 한국정보통신학회 2019년도 춘계학술대회
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    • pp.421-422
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    • 2019
  • 본 논문에서는 산업현장에서 안전사고 빈도가 높은 지게차 전복에 대비하여 적재중량을 측정하기 위해 적용할 수 있는 strain gauge 센서 모듈구현 결과를 제시한다. 센서 모듈은 strain gauge, LNA, LPF 및 ADC로 구성하였으며, 센서의 측량정밀도와 내구성을 높이기 위해 4개의 센서가 각각 4개의 anchor bolt에 삽입되는 구조로 제작하였다.

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Cyclic Load Testing of Concrete Expansion Anchors

  • Gary L. Barnes;Lee, Sang-Myung
    • 한국원자력학회:학술대회논문집
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    • 한국원자력학회 1996년도 춘계학술발표회논문집(4)
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    • pp.404-404
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    • 1996
  • In order to ensure a concrete expansion anchor is suitable for a given application, the load resistance behavior of the anchor must be known. ASTM E488 provides a standard method of testing expansion anchors for static and dynamic loads. Due to the many types of anchors available commercially and the large variability of applications, the ASTM does not delineate all details or requirements necessary to comprehensively determine the dynamic load behavior of concrete expansion anchors. A test program is presented in this paper which was developed and implemented to determine the cyclic load behavior of wedge-type concrete expansion anchors. Test results are also presented along with a discussion of the behavior of anchors, and their suitability for use.

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실물인장실험시 변형률계를 이용한 전주에 작용하는 응력분석 (Stress Analysis Acting on Electric Pole using Strain Gauge from Full Scale Pull-Out Test)

  • 안태봉
    • 조명전기설비학회논문지
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    • 제24권9호
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    • pp.49-55
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    • 2010
  • Many electric poles in the softground have been collapsed due to external load. In this study, 10 types of tests were performed with variation of location, numbers and depths of anchor blocks as well as depth of poles to find stresses acting on concrete electric poles. The stresses of concrete poles are relaxed at 600~700[kg] of tensile load, and stresses are concentrated at top of pole, and spread to lower part of pole. In the concrete pole collapse test, tensile load at failure was approximately 1,400[kg], which is twice of design load. As passive zone in the soil increases, the stresses acting on concrete pole are concentrated at lower part of pole based on moment arm earth pressure distribution.

Theoretical determination of stress around a tensioned grouted anchor in rock

  • Showkati, Alan;Maarefvand, Parviz;Hassani, Hossein
    • Geomechanics and Engineering
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    • 제8권3호
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    • pp.441-460
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    • 2015
  • A new theoretical approach for analysis of stress around a tensioned anchor in rock is presented in this paper. The solution has been derived for semi-infinite elastic rock and anchor and for plane strain conditions. The method considers both the anchor head bearing plate and its grouted bond length embedded in depth. The solution of the tensioned rock anchor problem is obtained by superimposing the solutions of two simpler but fundamental problems: A distributed load applied at a finite portion (bearing plate area) of the rock surface and a distributed shear stress applied at the anchor-rock interface along the bond length. The solution of the first problem already exists and the solution of the shear stress distributed along the bond length is found in this study. To acquire a deep understanding of the stress distribution around a tensioned anchor in rock, an illustrative example is solved and stress contours are drawn for stress components. In order to verify the results obtained by the proposed solution, comparisons are made with finite difference method (FDM) results. Very good agreements are observed for the teoretical results in comparison with FDM.

Pullout Test of Retrofit Anchors using Deformed Reinforcement and Adhesive

  • Choi, Dong-Uk;Kim, Yon-Gon
    • KCI Concrete Journal
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    • 제11권3호
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    • pp.201-210
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    • 1999
  • An experimental study was carried out to determine pullout behavior of a new type of anchor bolt that used deformed reinforcement and a commercial adhesive. Concrete slabs and columns with about 20-MPa compressive strength were used for 136 pullout tests performed. Test variables included anchor diameter (10 mm ~ 32 mm). embedment depth (10$\Phi$ or 15$\Phi$), edge effect. and Presence of transverse reinforcement in existing concrete. In Tyre-S test. where the edge or reinforcing steel effect was not included, the anchor Pullout strengths increased with increasing anchor diameters. Anchors with 15$\Phi$ embedment depth had higher Pullout strengths than those with 100 embedment depth The largest average Pullout load of 208 kN was determined for anchors made with D25 reinforcement and with 15$\Phi$ embedment depth. In Type-E tests, where the anchors were installed close to the edge of existing concrete, there were reductions in pullout strengths when compared to those determined in Type-S tests. In Type-ER tests, influence of the reinforcement in existing concrete on the anchor pullout strengths was examined using reinforced concrete and plain concrete columns Test results indicated that existing transverse reinforcement (column ties) did not help increase the pullout strength. The overall pullout test results revealed that the new anchor bolt can develop large pullout strengths while the anchors can be made of materials that are readily available in the market.

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Pullout capacity of shallow inclined anchor in anisotropic and nonhomogeneous undrained clay

  • Bhattacharya, Paramita
    • Geomechanics and Engineering
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    • 제13권5호
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    • pp.825-844
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    • 2017
  • This study aimed to find out the pullout capacity of inclined strip anchor plate embedded in anisotropic and nonhomogeneous fully saturated cohesive soil in undrained condition. The ultimate pullout load has been found out by using numerical lower bound finite element analysis with linear programming. The undrained pullout capacity of anchor plate of width B is determined for different embedment ratios (H/B) varying from 3 to 7 and various inclination of anchor plates ranging from $0^{\circ}$ to $90^{\circ}$ with an interval of $15^{\circ}$. In case of anisotropic fully saturated clay the variation of cohesion with direction has been considered by varying the ratio of the cohesion along vertical direction ($c_v$) to the cohesion along horizontal direction ($c_h$). In case of nonhomogeneous clay the cohesion of the undrained clay has been considered to be increased with depth below ground surface keeping $c_v/c_h=1$. The results are presented in terms of pullout capacity factor ($F_{c0}=p_u/c_H$) where $p_u$ is the ultimate pullout stress along the anchor plate at failure and $c_H$ is the cohesion in horizontal direction at the level of the middle point of the anchor plate. It is observed that the pullout capacity factor increases with an increase in anisotropic cohesion ratio ($c_v/c_h$) whereas the pullout capacity factor decreases with an increase in undrained cohesion of the soil with depth.