• Proceedings of the Earthquake Engineering Society of Korea Conference
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• 2006.03a
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• pp.620-627
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• 2006

강재기둥으로부터 전달되어 내려오는 모멘트 하중에 의한 베이스판의 변형을 고려한 앵커볼트의 설계방법에 대해 소개하였다. 기둥-베이스판 접합부의 설계를 위해 간략해석 모델 (Simple Beam Model) 이 개발되었으며 인장력과 모멘트 하중에 동시에 저항하는 앵커볼트의 설계를 위해 국부 메카니즘 개념이 도입되었다. 제안된 새로운 설계법을 적용하여 앵커볼트와 베이스판 사이의 최대지압력을 계산할 수 있었으며 이를 바탕으로 앵커볼트의 사이즈를 결정할 수 있었다. 본 논문에서는 상기 간략히 소개된 앵커볼트 설계법을 보다 상세히 기술하였다.

• Journal of Korean Society of Steel Construction
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• v.16 no.3 s.70
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• pp.325-332
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• 2004

Cross sections of steel-plate girder bridges are divided into three cross sections of non-composite, partially composite, and fully composite sections, according to their composite characteristics. The Korean provision for the partially and fully composite sections specifies general usage of the stud of shear connectors, whereas the one for the non-composite section specifies empirical usage of slab anchors. However, the actual behavior of the cross sections of steel-plate girder bridges using slab anchors is close not to the non-composite action, but to the partially composite action. Therefore analytical and experimental studies on partial composites of steel-plate girder bridges using slab anchors are performed in this study. Intial stiffness of the slab anchor is obtained by the experimental study for the first time, and the composite characteristic of simple-span and two-span continuous steel-plate girder bridges is investigated by the finite element analyses for the second time. Based on the obtained initial stiffness, the reduction effect of tensile stresses in the concrete-slab on the intermediate support of the continuous bridge is also considered herein.

• The Journal of Engineering Geology
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• v.22 no.1
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• pp.49-58
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• 2012

Anchor heads a recommonly exposed to surface weathering processes that cause physical damage by vibration and external forces. This study presents a new method of anchor-head installation that uses near-surface embedding based on analyses of concrete block failure. ABAQUS 3D numerical modeling performed to compare this method with the standard technique and to analyze the distribution of displacement and the stress pattern. In addition, application of the method to a real-world case was tested by in-situ measurements. The results show a maximum vertical stress of 9.73 MPa and vertical displacement of 1.34 mm. Field tests indicated that displacement of a concrete block was 3 to 4 times greater than that of an embedded bearing plate.

• Journal of Ocean Engineering and Technology
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• v.27 no.3
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• pp.15-21
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• 2013

Anchors are primarily designed and constructed to resist outwardly directed loads imposed on the foundation of a structure. These outwardly directed loads are transmitted to the soil at a greater depth by the anchors. Buried anchors have been used for thousands of years to stabilize structures. Various types of earth anchors are now used for the uplift resistance of transmission towers, utility poles, submerged pipelines, and tunnels. Anchors are also used for the tieback resistance of earth-retaining structures, waterfront structures, at bends in pressure pipelines, and when it is necessary to control thermal stress. In this research, we analyzed the uplift behavior of plate anchors in clay using a laboratory experiment to estimate the uplift behavior of plate anchors under various conditions. To achieve the research purpose, the uplift resistance and displacement characteristics of plate anchors caused by the embedment ratio, plate diameter, and loading rate were studied, compared, and analyzed for various cases.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2019.06a
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• pp.17-20
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• 2019

번호판 자동인식 (ALPR: Automatic License Plate Recognition)은 지능형 교통시스템 및 비디오 감시 시스템 등 많은 응용 분야에서 필요한 기술이다. 대부분의 연구는 자동차를 대상으로 번호판 감지 및 인식을 연구하였고, 오토바이를 대상으로 번호판 감지 및 인식은 매우 적은 편이다. 자동차의 경우 번호판이 차량의 전방 또는 후방 중앙에 위치하며 번호판의 뒷배경은 주로 단색으로 덜 복잡한 편이다. 그러나 오토바이의 경우 킥 스탠드를 이용하여 세우기 때문에 주차할 때 오토바이는 다양한 각도로 기울어져 있으므로 번호판의 글자 및 숫자 인식하는 과정이 훨씬 더 복잡하다. 본 논문에서는 다양한 각도로 주차된 오토바이 데이트세트에 대하여 번호판의 문자 인식 정확도를 높이기 위하여 2-스테이지 YOLOv2 알고리즘을 사용하여 오토바이 영역을 선 검출 후 번호판 영역을 검지한다. 인식률을 높이기 위해 앵커박스의 사이즈와 개수를 오토바이 특성에 맞추어 조절하였다. 그 후 기울어진 번호판을 검출한 후 영상 워핑(Image Warping) 알고리즘을 적용하였다. 모의실험 결과, 기존 방식의 인식률이 47,74%에 비해 제안된 방식은 80.23%의 번호판의 인식률을 얻었다. 제안된 방법은 전체적으로 오토바이 번호판 특성에 맞는 앵커박스와 이미지 워핑을 통해서 다양한 기울기의 오토바이 번호판 문자 인식을 높일 수 있었다.

• Geotechnical Engineering
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• v.12 no.3
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• pp.63-72
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• 1996

Plate anchors are often used for various types of offshore construction and maintenance works. When the plates are embedded in soft clay and subjected to sustanined allowable loads, creep may develop. This paper presents some results from laboratory model test designed to study the creep effect that develops with time for a shallow circular anchor subjected to sustained net loads that are less than the net ultimate uplift capacity. Based on the model test results, relationships among the net load, the rate of strain, and time are developed.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.14 no.5
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• pp.1219-1227
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• 1994

For Determination of the ultimate uplift capacity, the failure mechanism of the foundation by uplift should be correctly known. However, studies on the variation of the failure mechanism with the embedment ratio of anchor plate among those factors governing the uplift resistance are scarce. In this study. in an attempt to observe more clearly the variation of the failure mechanism with embedment ratio and to check applicability of existing formulae for the ultimate uplift capacity. a model test was performed with ground made of carbon rods, simulating a plane strain conditions. As a result, failure characteristics of shallow and deep anchor conditions were clearly classified. It was found that the analysis of a shallow anchor should be made prior to determination of the ultimate uplift capacity of a deep anchor.

• Journal of the Korea institute for structural maintenance and inspection
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• v.26 no.1
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• pp.29-38
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• 2022

Recently, seismic design for anchors is required, which are used for connecting structural members and non-structural and structural members. In this study, pull-out tests on the new expansion anchors which have been developed for cracked concrete. The anchors of 12 mm and 20 mm diameters were tested which are commonly used. Experiments were conducted on non-cracked concrete and cracked concrete to evaluate the seismic performance of the post-installed anchor. The experimental method complies with the specified test protocol (KCI, 2018). Three experimental variables are included in this study: presence of cracks, concrete compressive strength, and effective embedment depth. The strength of the anchors was evaluated with the characteristic capacity K_5% determined from the test results incorporated with the safety of 5% fractile. The characteristic capacity K_5% of the non-cracked and cracked concrete specified in KDS 14 20 54 are 9.8 and 7.0, respectively. Test results show that all groups except the three groups have higher characteristic capacity K_5% than the KDS code and the nominal strengths of the tested anchors can be determined with the obtained characteristic capacity K_5%.

• The Journal of Engineering Geology
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• v.30 no.4
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• pp.673-682
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• 2020

The ground shear force at the expected failure surface and resistance force due to reinforced anchor can act as important factors according to a failure type from the stability viewpoint at a slope. Furthermore, the anchor's axial force may vary at an anchor-reinforced slope due to ground weathering, settlement, and corrosion in the incompletely anti-corrosion treated steel wire strand at a ground where the bearing plate is installed. However, in case that the resistance force of the anchor is locally lost due to the variation of the anchor's axial force, the resistance force may not play the role so that the external force tends to be transferred to the surrounding anchors, causing an increase in the tensile force in the surrounding anchors. Accordingly, a stability problem at the entire slope may occur, which requires much attention. Thus, this study proposed a method to monitor a variation trend of the tensile force of anchors installed at a slope and infer the external stability at the entire slope considering the monitoring result.

• Proceedings of the Korean Geotechical Society Conference
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• 1995.10a
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• pp.1.2-12
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• 1995