• Title/Summary/Keyword: bolt anchor

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Seismic demand estimation of electrical cabinet in nuclear power plant considering equipment-anchor-interaction

  • Cho, Sung Gook;Salman, Kashif
    • Nuclear Engineering and Technology
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    • v.54 no.4
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    • pp.1382-1393
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    • 2022
  • This paper investigates the seismic behavior of an electrical cabinet considering the influence of equipment-anchor-interaction (EAI) that is generally not taken into consideration in a decoupled analysis. The hysteresis behavior of an anchor bolt in concrete was thereby considered to highlight this interaction effect. To this end, the experimental behavior of an anchor bolt under reversed cyclic loading was taken from the recently developed literature, and a numerical model for the anchor hysteresis was developed using the component approach. The hysteresis properties were then used to calibrate the multi-linear link element that is implemented as a boundary condition for the cabinet incorporating the EAI. To highlight this EAI further, the nonlinear time history analysis was performed for a cabinet considering the hysteresis behavior comparative to a fixed boundary condition. Additionally, the influence on the seismic fragility was evaluated for the operational and structural condition of the cabinet. The numerical analysis considering the anchor hysteresis manifests that the in-cabinet response spectra (ICRS) are significantly amplified with the corresponding reduction in the seismic capacity of 25% and 15% for an operational and structural safety condition under the selected protocols. Considering the fixed boundary condition over a realistic hysteresis behavior of the anchor bolt is more likely to overestimate the seismic capacity of the cabinet in a seismic qualification procedure.

A Study on Shear Capacity and Behavior of Large Sized Concrete Anchorage System (대형 콘크리트 앵커시스템의 전단성능 및 거동특성에 관한 연구)

  • Kim, Kang Sik;Shin, Sung Woo;Lee, Kwang Soo
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.15 no.5
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    • pp.82-91
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    • 2011
  • In this study, 24 prototype specimens were tested to find out the shear behavior and strength of large anchorage system exceeding 50mm(2") in anchor bolt diameter($d_0$) and 635mm(25") in effective embedment depth($h_{ef}$) not addressed by ACI349-06 Appendix B. Test variables are anchor bolt diameter($d_0$ = 63.5, 76.2, 88.9mm), effective embedment depth($h_{ef}$=635, 762mm), and edge distance($c_1$=381, 508, 762mm). Concrete compressive strength is constant($f_{ck}$=38MPa). Test results ($V_{test}$) were overestimated by $V_{aci06}$(shear strength by ACI 349-06) and $V_{ccd}$(shear strength by CCD method). In large anchorage system exceeding 50mm(2") of anchor bolt diameter($d_0$) and 635mm(25") of anchor bolt effective embedment depth($h_{ef}$), the bolt diameter variation and effective embedment depth($h_{ef}$) has no influence on the shear strenth, But, according to the analysis results of the feature ratio on edge distance($c_1$) and anchor bolt diameter, the feature ratio become smaller, which means anchor bolt diameter is bigger, predicted ratio of test results and predicted equation is larger. It was found that anchor bolt diameter is immediate cause of deterioration in the shear capacity of large anchorage system. To improve and extend the validity of current design recommendations further theoretical and numerical work is needed.

Simplified Finite Element Model of an Anchor Bolt Inserted Through Concretes Considering Clamping Forces (체결력을 고려한 콘크리트 삽입 앵커볼트의 간편 유한요소 모델)

  • Noh, Myung Hyun;Lee, Sang Youl;Park, Kyu Sik
    • Journal of the Computational Structural Engineering Institute of Korea
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    • v.26 no.4
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    • pp.293-300
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    • 2013
  • In this study we proposed a simplified finite element model of anchor bolt system inserted through concrete structures considering clamping forces. The three different finite element types using LS-DYNA are applied for numerical efficiency of the anchor bolt modeling. Combined beam and solid elements are used to reflect the tension state at internal part of anchor bolt due to torques. The clamping forces due to torques are considered by introducing a compression for a nut plane modeled by beam elements. The numerical examples show good agreement with different element types. Parametric studies are focused on the various effects of different element types on the induced axial and shear forces of anchor bolts considering clamping forces.

Finite Element Analysis of Concrete Railway Sleeper Damaged by Freezing Force of Water Penetrated into the Inserts (고속철도 콘크리트 궤도 매립전 내 침투수의 결빙압에 의한 균열손상해석)

  • Moon, Do-Young;Zi, Goang-Seup;Kim, Jin-Gyun;Jang, Seung-Yup
    • Journal of the Korean Society for Railway
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    • v.14 no.3
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    • pp.240-247
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    • 2011
  • Finite element analysis was undertaken to investigate the effect of freezing force of water unexpectedly penetrated into inserts used in railway sleeper on pullout capacity of anchor bolts for fixing base-plate onto concrete sleeper. Based on the in-situ investigation and measurement of geometry of railway sleeper and rail-fastener, the railway sleeper was modeled by 3D solid elements. Nonlinear and fracture properties for the finite element model were assumed according to CEB-FIP 1990 model code. And the pullout maximum load of anchor bolt obtained from the model developed was compared with experimental pullout maximum load presented by KRRI for verification of the model. Using this model, the effect of position of anchor bolt, amount of fastening force applied to the anchor bolt, and compressive strength of concrete on pull-out capacity of anchor bolts installed in railway sleeper was investigated. As a result, it is found that concrete railway sleepers could be damaged by the pressure due to freezing of water penetrated into inserts. And the pullout capacity of anchor bolt close to center of railway is slightly greater than that of the others.

A Study on the Concrete Breakout Capacity Evaluation of Medium-to-Large size CIP Anchor Bolts under Tension Loading (인장하중을 받는 중대형급 선설치 앵커볼트의 콘크리트파괴강도 평가를 위한 연구)

  • Park, Yong-Myung;Jeon, Myeong-Hui;Lee, Kun-Jun;Kim, Cheol-Hwan
    • Journal of Korean Society of Steel Construction
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    • v.23 no.4
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    • pp.493-501
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    • 2011
  • The $45^{\circ}$cone failure theory has been used for concrete anchor bolt design, but the CCD (concrete capacity design) method was adopted as a new design method in 2000. The method was allowed to be used, however, only for anchors with a diameter of less than 50 mm and an embedment depth of less than 635 mm because it is based on the experiment results from medium-sized to small anchor bolts. Therefore, it is necessary to develop a rational concrete breakout capacity equation for medium-sized to large anchor bolts. In this study, tension tests on an M56 cast-in-place single anchor bolt with an effective embedment depth of 400-450 mm were carried out for the five test specimens. Based on the test results together with the other recent test results, the applicability of the concrete breakout capacity equation in the current design code to the large to medium-sized anchor bolts with an embedment depth of 280-1,200 mm was estimated.

Pullout Test of Retrofit Anchors using Deformed Reinforcement and Adhesive

  • Choi, Dong-Uk;Kim, Yon-Gon
    • KCI Concrete Journal
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    • v.11 no.3
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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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Design and Construction of Green Slope Fabric Form on Cutting Slope (절토사면의 Nailing 보강 Fabric Form의 설계와 시공)

  • 송재헌;최영근
    • Proceedings of the Korean Geotechical Society Conference
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    • 2000.09a
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    • pp.81-92
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    • 2000
  • Green Slope(F.F.R : Fabric Form Reinforcement Method) is one of an environmental slope protection method at steep cutting sites. This method is that soil and rock at the steep slope is fixed using the environmental Fabric Form, Nail, Rock Bolt and Rock Anchor, And then, the surfaces covered with grasses or weeds. This method will be satisfied both safe slope protection and natural environment appearance. Green Slope is a useful method of the construction sites of steep cutting slopes.

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Flexural behavior of steel storage rack base-plate upright connections with concentric anchor bolts

  • Zhao, Xianzhong;Huang, Zhaoqi;Wang, Yue;Sivakumaran, Ken S.
    • Steel and Composite Structures
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    • v.33 no.3
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    • pp.357-373
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    • 2019
  • Steel storage racks are slender structures whose overall behavior and the capacity depend largely on the flexural behavior of the base-plate to upright connections and on the behavior of beam-to-column connections. The base-plate upright connection assembly details, anchor bolt position in particular, associated with the high-rise steel storage racks differ from those of normal height steel storage racks. Since flexural behavior of high-rise rack base connection is hitherto unavailable, this investigation experimentally establishes the flexural behavior of base-plate upright connections of high-rise steel storage racks. This investigation used an enhanced test setup and considered nine groups of three identical tests to investigate the influence of factors such as axial load, base plate thickness, anchor bolt size, bracket length, and upright thickness. The test observations show that the base-plate assembly may significantly influence the overall behavior of such connections. A rigid plate analytical model and an elastic plate analytical model for the overall rotations stiffness of base-plate upright connections with concentric anchor bolts were constructed, and were found to give better predictions of the initial stiffness of such connections. Analytical model based parametric studies highlight and quantify the interplay of components and provide a means for efficient maximization of overall rotational stiffness of concentrically anchor bolted high-rise rack base-plate upright connections.

Performance Evaluation of the Cast-in-place Anchor Bolt in Non-cracked Concrete used in Power Plant Facilities (비균열 콘크리트에 매립된 발전설비 정착부 선 설치 앵커의 구조성능 평가)

  • Kim, Dong-Ik;Jong, Woo-Young
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.20 no.11
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    • pp.250-258
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    • 2019
  • The seismic performance and stability of operating facilities installed in domestic power plants need to be verified because of the increased incidence of earthquakes resulting in power plant damage due to the overturning failure of electric operating facilities. In this study, a structural performance evaluation of the anchor bolts constructed to setup the operating facilities on concrete slabs was carried out through an on-site inspection of power plants, called Daechung-Dam. M10 J hook and M12 J hook anchor bolts were installed in the field unit. According to the ASTM E 488-96 specifications, anchor bolt pullout and shear tests were carried out and compared with the anchor-bolt design standards. The results from the tension and shear pullout tests showed that the M10 and M12 J hook anchor bolts had higher performance than the required design load. Thus, they were found to be safe enough. Nevertheless, more research in the field of analytical study will be needed in the near future.