• Title/Summary/Keyword: Post-installed anchors

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The Method for Determining the Effectiveness Factor(k value) of Concrete Expansion Anchors in accordance with ACI 355.2 (ACI 355.2에 의한 콘크리트 확장앵커의 유효계수(k값) 결정방법)

  • Lee, Byung Soo
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2020.06a
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    • pp.151-152
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    • 2020
  • Recently, concrete expansion anchors which are a type of post-installed mechanical anchors are widely used in reinforcement concrete structures. In order to be used in the reinforced concrete structures designed in accordance with ACI 318-19 or ACI 349-13, the structural performance tests of the concrete expansion anchors should be conducted in accordance with ACI 355.2. The effectiveness factor(k) of concrete expansion anchors should be determined through the reference tests and used for the design of anchorage to concrete according to ACI 318-19 or ACI 349-13. In this study, we will look into the method for determining the effectiveness factor(k) of concrete expansion anchors and anchorage design process of concrete expansion anchors by using the effectiveness factor(k) in accordance with ACI 349-19.

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Performance Evaluation of Post-installed Anchor according to Sleeve Length and Header Length (슬리브 및 헤드 길이에 따른 후설치 앵커의 인발성능평가)

  • Hur, Moo-Won;Chae, Kyoung-Hun;An, Yeong-Seung;Park, Tae-Won
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.25 no.2
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    • pp.8-15
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    • 2021
  • This study presents post-installed anchors whose heads and extension sleeves are improved. The optimal lengths of the extension sleeves and headers were analytically determined by simulations. As a result of analysis using Finite element method (FEM), 9.0mm and 3.0mm were determined as the optimal lengths of sleeves and headers respectively. In pull-out tests using the improved post-installed anchors, all specimens satisfied the coefficient of variation of 15%. Comparing the pull-out strengths of existing anchors and the improved anchors, it was increased by 1.25 times for anchors embedded with a depth of 50mm, and 1.54 times for 70mm. In the cases of high-strength concrete, the strengths were increased by 1.28 and 1.55 times for 50mm and 70mm respectively. Moreover, as a result of shear tests, the improved anchors perform the greater strength of 1.38 times than the existing anchors.

Structural Performance Evaluation of Anchors for Power Equipment Electrical Cabinets Considering On-Site Installation Conditions (현장 설치 조건을 고려한 발전설비 전기 캐비닛 정착부 앵커의 구조성능 평가)

  • Lee, Sang-Moon;Jung, Woo-Young
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.43 no.6
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    • pp.709-719
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    • 2023
  • In general, most of the electrical equipment responsible for control within power plants is housed in self-standing cabinets. These cabinets are typically fixed to a slab using post-installed anchors. Although the fixation method of using post-installed anchors provides stability, there is a risk of conductor failure due to external forces, including moments. However, the performance assessment of current anchors is only evaluated through uniaxial material tests. Therefore, the primary purpose of this study is to compare the static performance of post-installed anchors, considering on-site installation conditions, with their performance in material tests and to analyze the behavioral characteristics of the anchors. While conducting experiments using actual cabinets would be ideal, practical and spatial constraints make this approach difficult. As an alternative, experiments were conducted using a test specimen consisting of a steel column and a support. As a result, the pull-out performance of anchors reflecting on-site installation conditions was measured to be about 10% higher than that observed in material tests. The trends in load reduction and the point of maximum performance for the anchors also differed. To verify the reliability of the experimental study, a 3D FEM analysis was performed, which will provide predictive information on the loads transferred to the post-installed anchors for structural performance evaluations of electrical cabinets using shaking table test in the future.

Tensile and shear test method for post-installed mechanical anchors embedded in concrete (콘크리트 매입 후설치 앵커의 인장 및 전단시험방법)

  • Lee, Kwang-Myong;Lee, Chin-Yong;Jung, Sang-Hwa;Choi, Seul-Woo
    • Proceedings of the Korea Concrete Institute Conference
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    • 2009.05a
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    • pp.97-98
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    • 2009
  • In this study, tensile and shear test method for post-installed mechanical anchors embedded in concrete was proposed and the verification test was carried out to evaluate the design strength of anchor.

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A Study on the Pull-out Strength of Bond Type Anchors (부착식 앵커의 인발강도에 관한 연구)

  • Seo, Seong Yeon
    • Journal of Korean Society of Steel Construction
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    • v.30 no.2
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    • pp.105-114
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    • 2018
  • The use of post installed anchors with bond type has lately been increasing when it is necessary to repair, reinforce, or remodel structures. This method provides flexibility and simplicity for construction of structural members that require adhering or fixing. Meanwhile, strength evaluation of anchors with expansion type among post-installed anchors systems has nearly reached setting up stage like design code through continual experimental studies for the last ten years, but analyses or experimental studies on anchor system with bond type are not yet sufficient. Accordingly, the designers and builders of korea depend on foreign design codes since there are no exact domestic design code they could credit. In this study, the objectives are investigating the effects on pull-out strength of resin anchors embedded into plain concrete by pull-out experiment of resin anchors with variables such as anchor diameter, anchor interval, embedment depth and edge distance.

An Experimental Study on the Shear Strength of Chemical Anchors Embedded into Non Cracking Plain Concrete (비균열 무근콘크리트에 매입된 케미컬 앵커의 전단내력에 관한 실험적 연구)

  • Seo, Seong-Yeon
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.21 no.4
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    • pp.21-29
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    • 2017
  • The use of post installed anchors with adhesive type has lately been increasing when it is necessary to repair, reinforce, or remodel structures. This method provides flexibility and simplicity for construction of structural members that require adhering or fixing. Meanwhile, strength evaluation of anchors with expansion type among post installed anchors systems has nearly reached setting up stage like design code through continual experimental studies for the last ten years, but analyses or experimental studies on anchor system with adhesive type are not yet sufficient. Accordingly, the designers and builders of korea depend on foreign design codes since there are no exact domestic design code they could credit. In this study, the objectives are investigating the effects on adhesive strength of anchors embedded into plain concrete by shear experiments of anchors with variables such as edge distance, anchor interval, and load direction and supplying basic data for enactment of domestic design code.

An Performance Evaluation of Post-installed Anchor according to the Effective Embedment Length (유효묻힘깊이에 따른 후설치앵커의 인발성능평가)

  • Hur, Moo-Won;Chae, Kyoung-Hun;An, Yeong Seung;Hur, Moo-Won
    • Journal of the Korean Institute of Educational Facilities
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    • v.26 no.4
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    • pp.19-25
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    • 2019
  • Concrete wedge anchor is one of structural components to transfer load of an object attached to a primary structure. Recently, as retrofitting concrete structure is becoming a main issue, mechanical capacity of the anchor should be secured enough. In spite of the structural safety of Cast-in-place anchor, Post-installed anchor is more widely used with ease of placement or change of construction method. However, the post-installed anchors domestically produced have excessive coefficient of variation over 15% of ultimate tensile strength, which yields deteriorated quality in tensile strength. In this research, tensile strength test of anchors, which have improved sleeve and header and produced by a domestic company, was conducted for two variables, concrete strength and effective embedment depth. As a result, enough coefficients of variations were secured in all specimens. Also, in comparison to foreign products, the domestic ones have equal or higher performance.

Design Evaluation of the Post-installed Anchor considering Effective Embedded Depth and Concrete Strength (유효 묻힘 깊이와 콘크리트 강도를 고려한 후설치 앵커의 설계식 평가)

  • Hur, Moo-Won;Chae, Kyoung-Hun;Won, Jae-Sik;Park, Tae-Won
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.25 no.3
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    • pp.13-20
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    • 2021
  • Post-installed anchor is a structural material that connects structural and non-structural members to existing concrete members. However, there are cases where rebar interception and construction error occur at the site. In that case, measures are needed to prevent performance degradation of the rear-installation anchors. In this study, in order to evaluate the performance of torsional control expandable post-installed anchors for compressive strength and effective depth of the reference concrete was tested. The results of the most commonly used tests of M10 and M20 showed that had variable coefficients within 15%, satisfying the reliability presented in KCI(2017). It was also confirmed that the depth of the buried and the strength of concrete affect the strength of the pavement. Based on the results of the existing similar studies and the results of this study, the design equation of the post-installed anchor was proposed and the results were compared with the existing design.

Evaluation of Concrete Cone Breakout Strength of Expansion Anchors (익스팬션 앵커의 콘크리트 콘 파괴강도 평가)

  • Kim, Sung Yong;Kim, Kyu Suk
    • Journal of Korean Society of Steel Construction
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    • v.15 no.6 s.67
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    • pp.649-660
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    • 2003
  • The paper presents an evaluation of the tensile strength of the expansion anchor that can cause failure in the concrete based on the design of the anchorage. Tests of the heavy-duty anchor and the wedge anchor that are domestically manufactured and installed in plain concrete members are conducted to probe the effects of the embedded depth, concrete strength, and anchors spacing. The design of post-installed steel anchors is presented using the Concrete Capacity Design (CCD) approach. The CCD method is applied to predict the concrete failure load of the expansion anchor in plain concrete under monotonic loading for important applications. The concrete tension capacity of the fastenings with heavy-duty anchors and wedge anchors in plain concrete predicted using the CCD method is compared with the test results. For the CCD method, a normalization coefficient of 9.94 is appropriale for the nominal concrete breakout strength of an anchor or a group of wedge anchors in tension. On the other hand, a normalization coefficient of 11.50 is appropriate for the nominal concrete breakout strength of an anchor or a group of heavy-duty anchors in tension.