• Title/Summary/Keyword: anchorages

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A Study on the Safety of Anchoring for Ulsan M-10 Anchorage (울산항 M-10 정박지의 정박안전성 연구)

  • KIM, Se-Won
    • Journal of Fisheries and Marine Sciences Education
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    • v.21 no.2
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    • pp.291-305
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    • 2009
  • As you known well, Ulsan port is very famous for handling chemical products which occupies about 80% of quantities of all Korean ports. Many ship's operators prefer to handle liquid cargo es at proper anchorages instead of the berth for saving port expenses. Ulsan M-10 anchorage was assigned for handling liquid cargoes, however this anchorage's space is restricted by the oil pipeline which lays under seabed about 400m off from the center of M-10 anchorage, for which we have to consider of the external force and counter force for keeping the safety of anchoring. Where, external force is induced by wind, tidal currents and wave while counter force is induced by holding power of anchor/chain. In this study, author evaluated a method to analyze theoretically the limit of external force condition up to which an anchoring ship can keep her position without dragging, and for which applied to many kinds of combined Ships as mother ship of 50,000 DWT Tanker and 4 sizes of Tanker as alongsided ship.

Effect of Anchorage Number on Behavior of Reinforced Concrete Beams Strengthened with Glass Fiber Plates

  • Kaya, Mustafa;Kankal, Zeynel Cagdas
    • International Journal of Concrete Structures and Materials
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    • v.9 no.4
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    • pp.415-425
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    • 2015
  • Reinforced concrete beams with insufficient shear reinforcement were strengthened using glass fiber reinforced polymer (GFRP) plates. In the study, the effect of the number of bolts on the load capacity, energy dissipation, and stiffness of reinforced concrete beams were investigated by using anchor bolt of different numbers. Three strengthened with GFRP specimens, one flexural reference specimen designed in accordance to Regulation on Buildings Constructed in Disaster Areas rules, and one shear reinforcement insufficient reference specimen was tested. Anchorage was made on the surfaces of the beams in strengthened specimens using 2, 3 and 4 bolts respectively. All beams were tested under monotonic loads. Results obtained from the tests of strengthened concrete beams were compared with the result of good flexural reference specimen. The beam in which 4 bolts were used in adhering GFRP plates on beam surfaces carried approximately equal loads with the beam named as a flexural reference. The amount of energy dissipated by strengthened DE5 specimen was 96 % of the amount of energy dissipated by DE1 reference specimen. Strengthened DE5 specimen initial stiffness equal to DE1 reference specimen initial stiffness, but strengthened DE5 specimen yield stiffness about 4 % lower than DE1 reference specimen yield stiffness. Also, DE5 specimen exhibited ductile behavior and was fractured due to bending fracture. Upon the increase of the number of anchorages used in a strengthening collapsing manner of test specimens changed and load capacity and ductility thereof increased.

Study of exterior beam-column joint with different joint core and anchorage details under reversal loading

  • Rajagopal, S.;Prabavathy, S.
    • Structural Engineering and Mechanics
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    • v.46 no.6
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    • pp.809-825
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    • 2013
  • In the present study, in reinforced concrete structures, beam-column connections are one of the most critical regions in areas with seismic susceptibility. Proper anchorage of reinforcement is vital to enhance the performance of beam-column joints. Congestion of reinforcement and construction difficulties are reported frequently while using conventional reinforcement detailing in beam-column joints of reinforced concrete structures. An effort has been made to study and evaluate the performance of beam-column joints with joint detailing as per ACI-352 (mechanical anchorage), ACI-318 (conventional hooks bent) and IS-456(full anchorage conventional hooks bent) along with confinement as per IS-13920 and without confinement. Apart from finding solutions for these problems, significant improvements in seismic performance, ductility and strength were observed while using mechanical anchorage in combination with X-cross bars for less seismic prone areas and X-cross bar plus hair clip joint reinforcement for higher seismic prone areas. To evaluate the performances of these types of anchorages and joint details, the specimens were assembled into four groups, each group having three specimens have been tested under reversal loading and the results are presented in this paper.

Non-invasive steel haunch upgradation strategy for seismically deficient reinforced concrete exterior beam-column sub-assemblages

  • Kanchanadevi, A.;Ramanjaneyulu, K.
    • Steel and Composite Structures
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    • v.28 no.6
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    • pp.719-734
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    • 2018
  • Prior to the introduction of modern seismic guidelines, it was a common practice to provide straight bar anchorage for beam bottom reinforcement of gravity load designed building. Exterior joints with straight bar anchorages for beam bottom reinforcements are susceptible to sudden anchorage failure under load reversals and hence require systematic seismic upgradation. Hence in the present study, an attempt is made to upgrade exterior beam-column sub-assemblage of a three storied gravity load designed (GLD) building with single steel haunch. Analytical formulations are presented for evaluating the haunch forces in single steel haunch retrofit. Influence of parameters that affect the efficacy and effectiveness of the single haunch retrofit are also discussed. The effectiveness of the single haunch retrofit for enhancing seismic performance of GLD beam-column specimen is evaluated through experimental investigation under reverse cyclic loading. The single steel haunch retrofit had succeeded in preventing the anchorage failure of beam bottom bars of GLD specimen, delaying the joint shear damage and partially directing the damage towards the beam. A remarkable improvement in the load carrying capacity of the upgraded GLD beam-column sub-assemblage is observed. Further, a tremendous improvement in the energy dissipation of about 2.63 times that of GLD specimen is observed in the case of upgraded GLD specimen. The study also underlines the efficacy of single steel haunch retrofit for seismic upgradation of deficient GLD structures.

Production of Erythromycin Using a Carrier-Spported Mycelial Growth in a Fluidized-Bed Bioreactor (균사 증식 담체를 이용한 유동층 생물반응기에서 Erythromycin의 생산)

  • 김성환;배신규김정희
    • KSBB Journal
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    • v.4 no.3
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    • pp.241-245
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    • 1989
  • A carriersupported mycelial growth of Sreptomyces erythreus was applied to erythromycin fermentation sistem using celite as a support material. Hyphal growth through the pore matrices of the materials showed anchorages and provided a stable biofilm growth. When the phospate concentration was limited to 0.8g corn steep liquor/L(corresponding to 40mg KH2PO4/L), the specific production rate of erythromycin was increased from 557$\mu$g/g-cell.hr under unlimited condition to 2, 898 $\mu$g/g-cell.hr. A fluidized-bed bioreactor was operated for erythromycin production by a repeated fed-batch mode. The control of free mycelial concentration and the extension of production phase were considered important to maintain the reactor productivity at a desired level. The erythromycin production under phosphate-limited condition could be maintained for at least 600hrs.

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Study on Bursting Stress in Anchorage Zone of Prestressed Concrete Using Circular Anchorages (원형 정착구를 적용한 프리스트레스트 콘크리트 정착구역의 파열력에 관한 연구)

  • Choi, Kyu-Hyung;Lho, Byeong-Cheol
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.19 no.1
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    • pp.3-12
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    • 2015
  • Bursting stress in anchorage zone of post tension girder can be estimated based on Guyon's equation. The major parameters in calculating bursting stress are prestressing force and the distance ratio between concrete edge and anchorage plate. Although Guyon's equation can be applied to calculate bursting stress for rectangular typed as well as circular typed plate, there is some limitation of accuracy due to 2 dimensional analysis. Therefore this study is proposed to suggest a bursting stress equation based on 3 dimensional finite element method.

Shear Strength of Externally Post-Tensioned Concrete Beams (외부 포스트텐션 콘크리트 보의 전단강도)

  • Lee, Swoo-Heon;Kang, Thomas H.K.;Shin, Kyung-Jae
    • Journal of Korean Association for Spatial Structures
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    • v.15 no.1
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    • pp.57-64
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    • 2015
  • This paper shows the test results of continuous reinforced concrete beams with external post-tensioning rods. Six three-span beams were prepared and tested to fail. Three beams were designed to have flexure-dominating behavior and the others to have shear-critical behavior. In each group, one beam without external post-tensioning rods was designated as a control beam and two beams had the external post-tensioning rods of 18 mm or 22 mm diameter. External post-tensioning rods were installed within an interior span of 6000 mm. They show V-shaped configuration because two anchorages were located at the top of interior supports and a saddle pin at mid-span was installed at the bottom of the beam. Test results show that the load and shear capacities of strengthened beams were increased when compared with the control beam. Additionally, the measured shear strength was compared with the strength predicted by ACI 318-11 code equations. The detailed ACI 318-11 equation predicted the measured shear strength and failure location of the continuous beam reasonably well.

A study of rear seat belts geometric characteristics for rear seated occupants protections (뒷좌석 승객 보호를 위한 안전띠의 기하학적 특성에 대한 연구)

  • Youn, Younghan;Park, Jiyang;Lee, Seungsang;Kim, Minyoung
    • Journal of Auto-vehicle Safety Association
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    • v.7 no.1
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    • pp.45-50
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    • 2015
  • The protection of frontal seat passengers in both driver and front seated occupant has been more focused from the auto industries as well as regulatory bodies more than 40 years. Recently, their interests have been extended to rear seat occupants especially children and female occupants. However, the current available safety devices for the rear seat occupants are seat belt only. According to the previous researchers, the injury level of the rear seat passengers tend to be higher than the injury level of the frontal seat passengers. In this study, the optimal location of seat belts anchorages to enhance rear passengers crashworthiness are studied. FEM models are designed in accordance with regulation of KMVSS102, UN R44, UN R16, and UN R14. and three point belts are fitted on the HybridIII 5th percentile dummy and HybridIII 50th percentile dummy. The combined injury value used HIC15, Nij, Chest deflection, Femur force are used to evaluate rear seat belt anchorage optimal locations.

Ambient Vibration measurements and finite element modelling for the Hong Kong Ting Kau Bridge

  • Au, F.T.K.;Tham, L.G.;Lee, P.K.K.;Su, C.;Han, D.J.;Yan, Q.S.;Wong, K.Y.
    • Structural Engineering and Mechanics
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    • v.15 no.1
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    • pp.115-134
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    • 2003
  • The Ting Kau Bridge in Hong Kong is a cable-stayed bridge comprising two main spans and two side spans. The bridge deck is supported by three towers, an end pier and an abutment. Each of the three towers consists of a single reinforced concrete mast which reduces its section in steps, and it is strengthened by transverse cables and struts in the transverse vertical plane. The bridge deck is supported by four inclined planes of cables emanating from anchorages at the tower tops. In view of the threat from typhoons, the dynamic behaviour of long-span cable-supported bridges in the region is always an important consideration in their design. This paper is devoted to the ambient vibration measurements of the bridge for evaluation of dynamic characteristics including the natural frequencies and mode shapes. It also describes the modelling of the bridge. A few finite element models are developed and calibrated to match with the field data and the results of subsequent structural health monitoring of the bridge.

A study on Maritime Safety Audit(MSA) and it's Guideline (해상교통안전진단제도 및 기술기준 연구)

  • Cho, Ik-Soon;Kim, Kyoung-Mi;Jang, Woon-Jae
    • Journal of Korea Ship Safrty Technology Authority
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    • s.28
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    • pp.36-45
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    • 2010
  • While the vessel become bigger and high speed, navigational passages become narrow due to an enlargement of all sorts of new ports, sea-crossing bridges and anchorages, leading to the high probability of marine accidents. Furthermore, a constant increase in the maritime transportation and the traffic volume on the sea led to a variety of sea traffic environments and it is a trend for the demand for the sea transportation environment to increase steadily. At this point of time, the Ministry of Land, Transport, and Maritime Affairs introduced the Korea Maritime Safety Laws evaluating the degree that The Safety Audit System for maritime transport, which evaluates the degree that all kinds of port facilities installed temporarily or installed into navigational passages, and the installations and repair constructions of S.O.C. facilities affect ships' traffic safety, was introduced through Korea Maritime Safety Laws and went into effect from November 28th, 2009. This study was performed to introduce an outline including the concept and purpose of the Maritime Safety Audit(MSA) system for maritime transport and the technological guidelines for scientific and standardized enforcement, thereby analyzing the system.

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