• 대한토목학회논문집
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• 제43권6호
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• pp.709-719
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• 2023

일반적으로 발전소 내 제어를 담당하는 대부분의 전기 설비는 자립식 캐비닛으로, 후설치 앵커를 사용하여 슬래브에 고정하는 정착 방식이 주로 사용된다. 정착부 앵커의 경우 외력이 작용될 시 모멘트 하중 등에 의한 전도의 위험성에 노출되지만 현행 앵커에 대한 성능 검토는 1축 재료 시험으로만 평가되고 있다. 따라서 본 연구는 현장 설치 조건이 반영된 후설치 앵커의 정적 성능 실험을 통하여 재료 시험과의 성능을 비교하고 앵커의 거동 특성을 분석하는 것이 주목적이다. 실제 캐비닛을 이용하여 실험을 진행하는 것이 타당하지만 경제적, 공간적 제약으로 수행하기에 어려움이 있어 강재 기둥과 받침으로 구성된 실험체로 대체하여 수행하였다. 결과적으로 현장 설치 조건을 반영한 앵커의 인발 성능이 재료 시험 대비 약 10 % 높게 측정되었으며, 앵커의 하중 감소 경향 및 최대 성능이 발현되는 시점도 상이한 것으로 나타났다. 한편, 실험적 연구의 신뢰성을 검증하기 위하여 3D FEM 해석을 수행하였으며, 이를 통해 향후 진동대를 이용한 전기 캐비닛의 구조 성능 평가 시 후설치 앵커에 전달되는 예측 가능한 하중 정보를 제공하고자 한다.

• KCI Concrete Journal
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• 제13권2호
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• pp.33-41
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• 2001

This paper presents the crack effect on CIP anchors and prediction of tensile capacity, as governed by concrete cone failure. Single anchors where located at center of concrete specimen. Three different types of cracks such as crack width of 0.2 mm and 0.5 mm, crack depth of 10 cm and 20cm , and crack location of center and off-center point were simulated. Static tensile load was applied to 7/8-in. CIP anchors of 10 cm and 20 cm embedment length in concrete with compressive strength of 280 kgf/$\textrm{cm}^2$. Tested pullout capacities were compared to the values determined using current design methods (such as ACI 349-97, ACI 349 revision and CEB-FIP which is based on CCD Method). The comparison of CCD Method and ACI revision showed almost the same values in uncracked concrete specimen. In cracked concrete, CCD Method predicted conservative values. Three-dimensional non-linear FEM modeling also has been performed to determine the stresses distribution and crack inclination.

• 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.

• 한국공간구조학회논문집
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• 제23권2호
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• pp.53-60
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• 2023

Recently, a novel cast-in specialty insert was developed in Korea as an anchor for lightweight pipe supports, including fire-protection pipes. As these pipe supports and anchors play a critical role in transferring loads of fire-protection pipes to structural members, it is crucial to evaluate their seismic performance before applying the newly developed insert. In this study, the seismic shear performance of the insert anchors was evaluated through cyclic loading tests based on the loading protocols of ACI 355.2 and FEMA 461. Initially, five monotonic loading tests were conducted on the insert anchors in cracked concrete, followed by cyclic loading tests based on the monotonic test results. The findings revealed that the insert anchors exhibited negligible decrease in shear strength even after cyclic loading. Furthermore, a comparison of the maximum load and displacement of the insert anchors obtained under the loading protocols of ACI 355.2 and FEMA 461 was performed to investigate the applicability of the FEMA 461 loading protocol for anchor performance evaluation.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2000년도 봄 학술발표회 논문집
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• pp.387-394
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• 2000

In the present study, laboratory pull-out tests with screw anchors are carried out to investigate behavior characteristics of underground structures applied uplift seepage forces. Small scaled pull-out tests in sand were conducted under saturated condition. And then, it was observed that the upward displacement as well as the pullout load varied with spacing of the anchor. Also, analyses have been performed with the aim of pointing out the effects of various parameters on the group effect of the screw anchors.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제6권10호
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• pp.2567-2586
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• 2012

Localization of sensor nodes is a key technology in Wireless Sensor Networks(WSNs). Trilateration is an important position determination strategy. To further improve the localization accuracy, a novel Trilateration based on Point In Triangle testing Localization (TPITL)algorithm is proposed in the paper. Unlike the traditional trilateration localization algorithm which randomly selects three neighbor anchors, the proposed TPITL algorithm selects three special neighbor anchors of the unknown node for trilateration. The three anchors construct the smallest anchor triangle which encloses the unknown node. To choose the optimized anchors, we propose Point In Triangle testing based on Distance(PITD) method, which applies the estimated distances for trilateration to reduce the PIT testing errors. Simulation results show that the PIT testing errors of PITD are much lower than Approximation PIT(APIT) method and the proposed TPITL algorithm significantly improves the localization accuracy.

• Geomechanics and Engineering
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• 제8권4호
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• pp.595-613
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• 2015

An experimental investigation into the uplift capacity of horizontal square plate anchors in sand with and without geogrid reinforcement is reported. The parameters investigated are the effect of the depth of the single layer of geogrid, vertical spacing of geogrid layers, number of geogrid layers, length of geogrid layers, the effects of embedment depth, and relative density of sand. A series of three dimensional finite element analyses model was established and confirmed to be effective in capturing the behaviour of plate anchor-reinforced sand by comparing its predictions with experimental results. The results showed that the geogrid reinforcement had a considerable effect on the uplift capacity of horizontal square plate anchors in sand. The improvement in uplift capacity was found to be strongly dependent on the embedment depth and relative density of sand. A satisfactory agreement between the experimental and numerical results on general trend of behaviour and optimum geometry of reinforcement placement is observed. Based on the model test results and the finite element analyses, optimum values of the geogrid parameters for maximum reinforcing effect are discussed and suggested.

• 한국안전학회지
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• 제28권5호
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• pp.49-53
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• 2013

This paper describes the assessment of seismic performance of the concrete gravity dam seismically reinforced by post-tensioned anchors. In order to evaluate the seismic performance, the response spectrum analyses have been carried out for 7 different configurations of the post-tensioned anchors, and then their performance improvement in the maximum tensile and compressive stresses is compared to each other. The comparative results demonstrate that the layout of the post-tensioned anchors strongly influences the seismic performance of the concrete gravity dam. In this study, the slightly-inclined vertical anchorage system shows the largest improvement on the overall performance of the seismically-excited concrete gravity dam.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2010년도 춘계 학술발표회
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• pp.832-839
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• 2010

The pulse discharge anchor is a method to increase the capacity of anchors using electric discharge geotechnical technologies, which is also known as pulse discharge and electric-spark technologies. The pulse discharge anchor has bulbed bond length that is expanded by high voltage electrokinetic pulse energy. 24 anchors were installed in the weathered soil and sandy clay at the Geotechnical Experimentation Site at Sungkyunkwan University in Suwon, Korea and attached strain gauge at 10 anchors. The numerical predictions by Beam-Column analysis were compared with observed measurements in a field load test.

• 산업경영시스템학회지
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• 제19권38호
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• pp.159-168
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• 1996

Appraisal format is the methods that is used to gether informations related to performance behaviors. Appraisal format has descriptive characteristics including evalustion dimensions, anchors, scales. The purpose of this paper is to study the effectiveness of a format characteristics of the appraisal results through literature review and to explore more approprate appraisal format through comparing three types of formats, graphic scales, BARS, BOS. According to the results, rating format's characteristics can affect the quality of appreisa results in that appraisal format can provide rators with evaluation standards which help raters to evaluate effectively. Specific dimensions are better than gernal one dimension. The effectiveness of scale in some degrees depends on development procedure. In general anchors are important to reduce rating errors and behavioral anchors are better than numeric anchors, The systematically developed BARS and BOS can reduce rating erros but graphic scales has limitstions.