• Title/Summary/Keyword: anchoring method

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A study on development of methods to rehabilitate the damaged prestressed concrete beam using glass fiber (유리섬유를 이용한 손상된 프리스트레스트 콘크리트보의 보강공법 개발연구)

  • 한만엽;이택성;강원호
    • Proceedings of the Korea Concrete Institute Conference
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    • 1998.10b
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    • pp.815-820
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    • 1998
  • Many composite girder bridges have been constructed for about thirty five years. Nowadays they are aged or deteriorated because of th increase in traffic and vehicle loads. In this study, the effect of strengthening with glass fiber sheet is investigated to estimate the possibility for appling for damaged prestressed concrete bridges. One normal and eight cracked specimens which had been preloaded were tested. The cracked specimens were strengthened with either external prestressing or bonding glass fiber sheet, or using both methods. The results showed that the maximum loads are almost same for both methods. So it seems that the strengthening with glass fiber sheet can be used for strengthening damaged prestressed concrete girders. It is important that proper devices should be selected to prevent glass fiber sheet from premature bonding failure below its maximum load, which is similar to end anchorage problem in external prestressing method. It is proved that the devices proposed in this paper have sufficient anchoring capability to increase load carrying capacity.

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Control of Liquid Crystal Pretilt Angle using Polymerization of Reactive Mesogen

  • Jo, Soo-In;Lee, You-Jin;Kim, Young-Ki;Yoon, A-Ra;Choi, Sang-Woong;Kim, Jae-Hoon
    • 한국정보디스플레이학회:학술대회논문집
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    • 2009.10a
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    • pp.604-606
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    • 2009
  • We propose a method to control the pretilt angle of liquid crystal (LC) by doping a proper amount of UV curable reactive mesogen (RM) monomers in hometropic polyimide (PI). The intermediate pretilt angles are produced by anchoring competition between homeotropic PI and the polymerized RM which direction is along the LC molecules under electric field.

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CAUSE OF TECHNICAL FAILURES OF CONICAL CROWN-RETAINED DENTURE (CCRD): A CLINICAL REPORT

  • Yi Yang-Jin;Cho Lee-Ra;Park Chan-Jin
    • The Journal of Korean Academy of Prosthodontics
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    • v.41 no.6
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    • pp.714-719
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    • 2003
  • Conical crown-retained denture (CCRD) has been used as a very effective treatment method in cases with few remaining teeth with heterogeneous prognosis. However, in spite of many advantages of CCRD, high technical failure rate was a problem to be considered. Incorrect path of insertion and excessive retention were thought to be the main cause of technical failure and to result from laboratory procedure with a coping misfit and/or a coping transfer error. In order to prevent this error, secure anchoring of inner coping and re-examination and milling of convergence angle were recommended on the master model from pick-up impression.

Database of Navigational Environment Parameters (Water Depth, Sediment Type and Marine Managed Areas) to Support Ships in an Emergency

  • Kim, Tae-Ho;Yang, Chan-Su
    • Journal of Navigation and Port Research
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    • v.43 no.5
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    • pp.302-309
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    • 2019
  • This study introduces the navigational environment database(DB) compiling water depth, sediment type and marine managed areas (MMAs) in coastal waters of South Korea. The water depth and sediment data were constructed by combining their sparse points of electronic navigation chart and survey data with high spatial resolution using the inverse distance weighting and natural neighbor interpolation method included in ArcGIS. The MMAs were integrated based on all shapefiles provided by several government agencies using ArcGIS because the areas should be used in an emergency case of ship. To test the validity of the constructed DB, we conducted a test application for grounding and anchoring zones using a ship accident case. The result revealed each area of possible grounding candidates and anchorages is calculated and displayed properly, excluding obstacle places.

Sternal Fracture Fixation with a Steel Wire: The New "Timala" Technique

  • Timala, Rabindra Bhakta;Panthee, Nirmal
    • Journal of Trauma and Injury
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    • v.34 no.3
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    • pp.170-176
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    • 2021
  • Purpose: Traumatic sternal fractures are rare but quite disabling injuries. Timely fixation of sternal fractures reduces pain and prevents respiratory complications. However, the fixation technique should be simple, effective, and readily available in local circumstances. Methods: From January 2014 to March 2020, seven patients with sternal fracture/dislocation underwent steel wire fixation with the new "Timala" technique. In this technique, adjacent ribs are anchored with two steel wires to form an "X" in front of the fractured segment of the sternum. Patients were followed up clinically and radiologically. Results: Six of the patients were men and one was a female. Five of them had injuries due to falls and two were injured in road traffic accidents. Their age ranged from 18 years to 76 years, with a median age of 41 years. All seven patients experienced immediate recovery from pain and showed evidence of fracture healing on postoperative chest X-rays and clinical examinations. Conclusions: Anchoring ribs to fix the sternum with steel wire is a safe, effective, easily available, and reproducible method to fix sternal fractures or dislocations.

Evaluation of dynamic behaviors of gravity-based structures under seismic load considering fluid-structure-ground interactions

  • Hyo-Jin Kim;Sunghun Jung;Seongpil Cho
    • Structural Engineering and Mechanics
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    • v.88 no.3
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    • pp.251-262
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    • 2023
  • This paper presents a method for assessing the dynamic responses of gravity-based structures (GBS) under various seismic loads, with a focus on fluid-structure-ground interactions. Models of GBSs and their surrounding environments were developed, incorporating interaction effects among the structure, seawater, and seabed. Dynamic responses of the GBS subjected to three seismic loads-Chi-Chi, Northridge01, and Northridge02-were calculated, with consideration of both horizontal and vertical accelerations, as well as displacements. Parametric studies indicated that the primary factors affecting the dynamic responses of GBS were seismic loads characterized by significant input forces and accelerations. The frictional force on the ground had minimal impact on the horizontal and vertical displacements of the GBS. Weight emerged as a critical factor in anchoring the GBS to the ground and minimizing vertical accelerations and displacements.

Densification of Cu-50%Cr Powder Compacts and Properties of the Sintered Compacts (Cu-50%Cr 분말성형체의 치밀화 및 소결체 물성)

  • 김미진;정재필;도정만;박종구;홍경태
    • Journal of Powder Materials
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    • v.7 no.4
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    • pp.218-227
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    • 2000
  • It is well known that the Cu-Cr alloys are very difficult to be made by conventional sintering methods. This difficulty originates both from limited solubility of Cr in the Cu matrix and from limited sintering temperature due to high vapor pressures of Cr and Cu components at the high temperature. Densification of Cu-50%Cr Powder compacts by conventional Powder metallurgy Process has been studied. Three kinds of sintering methods were tested in order to obtain high-density sintered compacts. Completely densified Cu-Cr compacts could be obtained neither by solid state sintering method nor by liquid phase sintering method. Both low degree of shrinkage and evolution of large pores in the Cu matrix during the solid state sintering are attributed to the anchoring effect of large Cr particles, which inhibits homogeneous densification of Cu matrix and induces pore generation in the Cu matrix. In addition, the effect of undiffusible gas coming from the reduction of Cu-oxide and Cr-oxide was observed during liquid phase sintering. A two-step sintering method, solid state sintering followed by liquid phase sintering, was proved to have beneficial effect on the fabrication of high-dendsity Cu-Cr sintered compacts. The sintered compacts have properties similar to those of commercial products.

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A Study on Decisions on Investment Factors in the Development of Local Fishing Harbors (지방어항개발의 투자결정요인 분석 - 충청남도 어항 중심으로 -)

  • Lee, Kwang-Nam;Jung, Jin-Ho;Choi, Jae-Wook
    • Ocean and Polar Research
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    • v.33 no.4
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    • pp.473-483
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    • 2011
  • In the recent WTO/DDA negotiations, discussions are progressing to forbid fishery subsidies which have negative effect on the natural environment and the fishery resources and to lower or to eliminate the tariff/non-tariff barriers that distort trade liberalization. As a result, linking to the weak structural environment of Korea's fishing villages; such a scheme has jeopardized the livelihood of fishermen who settle down in local fishing harbors. Against this backdrop, the government is attempting to positively respond to changes in the fishing environment in a number of different ways: promotion of fishing tourism, fishing harbor reinforcement in function, developing fishing villages, and harbors. With respect to investment by priority in fishing harbor development, it is very important to appropriately select investment targets based on objective criteria. A small number of harbors are chosen and investment plans by harbor are systematically devised, economic feasibility and the effects of investment are analyzed and reviewed in relation to each target harbor. This paper is designed to review and assess objective evaluation methods and the degree of importance for the designation of target harbors, dealing with local harbors in Chung Nam Do as a model. Each local government has tried to reorganize existing harbors and develop new harbors, considering a fall in the number of fishing vessels and the expansion of maritime leisure activities. In order to overcome the limit of existing harbors in function, to raise the income of fishermen, and to activate tourism, they have shifted their focus from simple functions such as vessel evacuation and anchoring to harbor beautification, which can work as a basis for fishing tourism. This paper points out that the AHP analysis method for prioritizing local harbors in Chung Nam Do should help to be chosen target harbors in other cities and provinces. Each local government has attempted to reorganize existing harbors and to develop new harbors, taking into consideration the decline in the number of fishing vessels and the expansion of maritime leisure activities. In order to overcome the limited number of functional harbors, to raise the income of fishermen, and to boost tourism, they have shifted their focus from simple functions, such as vessel evacuation and anchoring, to harbor beautification, which can work as a basis for fishing tourism. This paper shows that the AHP analysis method for prioritizing local harbors in Chungcheongnam-do could aid in the effective selection of target harbors in other cities and provinces.

Pullout Test of Reinforcement with End Mechanical Anchoring Device (단부 기계적 정착장치를 갖는 철근의 뽑힘강도)

  • 김용곤;임원석;최동욱
    • Journal of the Korea Concrete Institute
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    • v.14 no.3
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    • pp.430-439
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    • 2002
  • The development of reinforcing steel is required in reinforced concrete structures. The standard hooks that have been widely used for the tensile development in the beam-column joints tend to create difficulties of construction such as steel congestion as the member cross sections are becoming smaller due to the use of higher strength concrete and higher grade steel. Using the reinforcing bars with end mechanical anchoring device (headed reinforcement) provides potential economies in construction such as reduction in development lengths, simplified details, and improved responses to cyclic loadings. In this paper, the pullout strengths and behaviors of the headed reinforcement were experimentally studied. In 33 pullout tests performed using D25 deformed reinforcing bars, the test parameters were embedment depth, edge distance, head size, and the use of transverse reinforcement. The pullout strengths determined from tests closely agreed with the pullout strengths predicted using the CCD method. The pullout strengths increased with increasing embedment depths nd edge distances. The strengths tend to increase with the use of larger heads. From the experimental program where the effect of the transverse reinforcement was examined, a modification factor to the CCD was suggested to represent the effect of such reinforcement that is installed across the concrete failure plane on the pullout strengths.

The Three-Bite Technique: A Novel Method of Dog Ear Correction

  • Jaber, Omar;Vischio, Marta;Faga, Angela;Nicoletti, Giovanni
    • Archives of Plastic Surgery
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    • v.42 no.2
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    • pp.223-225
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    • 2015
  • The closure of any circular or asymmetric wound can result in puckering or an excess of tissue known as a 'dog ear'. Understanding the mechanism of dog ear formation is a fundamental requirement necessary to facilitate an appropriate treatment. Many solutions have been reported in the literature, but in all cases, the correction entails the extension of the scar and the sacrifice of the dermal plexus. Here, we propose a novel technique of dog ear correction by using a three-bite suture that sequentially pierces the deep fascial plane and each dog ear's margin, thus allowing for flattening the dog ear by anchoring the over-projecting tissue to the deep plane. The three-bite technique proved to be a fast, easy, and versatile method of immediate dog ear correction without extending the scar, while maintaining a full and complete local skin blood supply.