• Journal of Korea Port Economic Association
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• v.25 no.1
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• pp.29-46
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• 2009

According to construction work of No. 2 Lotte world, the alternative pier is under construction in Dongsam-dong Yeongdo-gu to accommodate small boats. As a result of that, in order to procure route of small boats passage,0-2 Anchorage used to bunkering or waiting for berth should be reduced, 220m. It is expected that the risk of passage and congestion around the anchorage could be increased because of the traffic of small boat using the alternative pier. Therefore, it is needed to enlarge the O-2 Anchorage 250m toward to inner breakwater. According to result of analyzing traffic circumstance and weather condition of anchorage near the Busan inner fairway, and to procure of alternative anchorage in order to resolve the problem caused by reduction of O-2 Anchorage, no problems incurred. In conclusion, reduction & enlargement of area of new O-2 Anchorage is expected to resolving of congestion & reducing of risk of traffic at O-2 Anchorage, and to operating O-2 Anchorage, efficiently.

• The korean journal of orthodontics
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• v.34 no.2 s.103
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• pp.197-203
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• 2004

Tweed-Merrifield directional force technology is a very useful concept, especially for the treatment of Glass II malocclusion. It has contributed to treating a favorable counter-clockwise skeletal change and balanced face, while head gear force using high pull J-hook (HPJH) in an appropriate direction is also essential to influence such results. Clinicians have encountered some problems concerning patients' compliance; however skeletal anchorage has been used widely of late because it does not necessitate patients' compliance, yet produces absolute anchorage. In this case, a good facial balance was obtained by Tweed-Merrifield directional force technology using HPJH together with skeletal anchorage, which provided anchorage control in the maxillary posterior area, torque control in the maxillary anterior area, and mandibular response. This indicates 4hat skeletal anchorage can be used to reinforce sagittal and vortical anchorage in the maxillary posterior area during the retraction of anterior teeth. The author used HPJH for torque control, Intrusion, and the bodily movement of maxillary anterior teeth during on masse movement. However, it is thought that such a result nay also be achieved by substituting mini- or microscrews for HPJH. Consequently, Tweed-Merrifield directional force technology using skeletal anchorage for the treatment of Class II malocclusion not only maximiaes the result of treatment but can also minimize patients' compliance.

• Smart Structures and Systems
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• v.20 no.2
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• pp.181-195
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• 2017

In this study, the severity of damage in tendon anchorage caused by the loss of tendon forces is quantitatively identified by using the PZT interface-based impedance monitoring technique. Firstly, a 2-DOF impedance model is newly designed to represent coupled dynamic responses of PZT interface-host structure. Secondly, the 2-DOF impedance model is adopted for the tendon anchorage system. A prototype of PZT interface is designed for the impedance monitoring. Then impedance signatures are experimentally measured from a laboratory-scale tendon anchorage structure with various tendon forces. Finally, damage severities of the tendon anchorage induced by the variation of tendon forces are quantitatively identified from the phase-by-phase model updating process, from which the change in impedance signatures is correlated to the change in structural properties.

• Proceedings of the Korea Concrete Institute Conference
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• 2000.04a
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• pp.657-662
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• 2000

This paper presents the results from experimental study that investigated to explore the load transfer characteristics of post-tensioning anchorage zones. The experimental program investigated the primary variables which affect the ultimate load, lateral strains and crack width: concrete compressive strength, details of reinforcement and shape of anchorage. Through this research, it was found that the governing factor of the ultimate load was not compressive cylinder strength but tensile splitting strength. Ultimate load was increased and lateral strain was decreased as the ratio of spiral increased because the lateral expansion of th concrete inside the spiral was restrained by the spiral. Furthermore, the shape of anchorage which can diminish the wedge effect of anchorage and disperse the anchorage force in various depths was more effective.

• Proceedings of the Korean Geotechical Society Conference
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• 2008.10a
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• pp.629-640
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• 2008

South anchorage(AN1, Myodo side) of supension bridge between Myodo and Gwangyang is designed as rock anchorage with 36m anchor length using the resistance of rock mass in Myodo. Checking the overall stability of the anchorage, we considered rock joints, bedding planes, fault zones and condition of rock structure in situ by analysis results for photo-lineaments, aerial photograph interpretation and drill-hole logs are considered. This anchorage consists of an access shaft, adit, and the upper and lower concrete bearing plate to introduce pre-stressing force into rock mass.

• Computers and Concrete
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• v.11 no.6
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• pp.493-513
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• 2013

Direct displacement-based design (DDBD) represents an innovative philosophy for seismic design of structures. When structural considerations are more critical, DDBD design should be carried on the basis of limiting material strains since structural damage is always strain related. In this case, the outcome of DDBD is strongly influenced by the displacement demand of the structural element for the target limit strains. Experimental studies have shown that anchorage slip may contribute significantly to the total displacement capacity of R/C column elements. However, in the previous studies, anchorage slip effect is either ignored or lumped into flexural deformations by applying the equivalent strain penetration length. In the light of the above, an attempt is made in this paper to include explicitly anchorage slip effect in DDBD of R/C column elements. For this purpose, a new computer program named RCCOLA-DBD is developed for the DDBD of single R/C elements for limiting material strains. By applying this program, more than 300 parametric designs are conducted to investigate the influence of anchorage slip effect as well as of numerous other parameters on the seismic design of R/C members according to this methodology.

• Structural Engineering and Mechanics
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• v.18 no.4
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• pp.475-491
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• 2004

Anchorage devices play an important role in post-tensioned bridge structures since they must sustain heavy loads in order to permit the transfer of the prestressing force to the structure. In external prestressing, the situation is even more critical since the anchorage mechanisms, with the deviators, are the only links between the structure and the tendons throughout the service life of the structure. The behaviour of anchorage devise may be studied by using the finite element method. To do so, each component of the anchorage must be adequately represented in order to approximate the anchor mechanism as accurately as possible. In particular, the modelling of the jaw/tendon device may be carried out using the real geometry of these two components with an appropriate constitutive contact law or by replacing these components by a single equivalent. This paper presents the numerical study of a mono-strand anchorage device. The results of a comparison between two different representations of the jaw/tendon device, either as two distinct components or as a single equivalent, will be examined. In the double-component setup, the influence of the wedge configuration composing the jaw, and the influence of lubrication of the anchor, will be assessed.

• Magazine of the Korea Concrete Institute
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• v.8 no.3
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• pp.209-218
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• 1996

The purpose of the present study is to explore the effects of local reinforced type and to suggest reliable failure mechanism and the design criteria on the anchorage zones of the precast prestressed concrete bridges. To accomplish these objectives, a comprehensive experimental and analytical study has been conducted. From this study, the cracking and ultimate load capacities for spirally reinforced anchorage zone are found to be larger than those for orthogonal reinforced anchorage zone. This indicate the effectiveness of spiral reinforcement in controlling the cracking. And realistic failure mechanism and design criteria of prestressed anchorage zones based on the present study are suggested.

• Steel and Composite Structures
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• v.26 no.1
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• pp.115-123
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• 2018

Steel-concrete composite structure is widely applied to bridge engineering due to their outstanding mechanical properties and economic benefit. This paper studied a new type of steel-concrete composite anchorage system for a self-anchored suspension bridge and focused on the mechanical behavior and force transferring mechanism. A model with a scale of 1/2.5 was prepared and tested in ten loading cases in the laboratory, and their detailed stress distributions were measured. Meanwhile, a three-dimensional finite element model was established to understand the stress distributions and validated against the experimental measurement data. From the results of this study, a complicated stress distribution of the steel anchorage box with low stress level was observed. In addition, no damage and cracking was observed at the concrete surrounding this steel box. It can be concluded that the composite effect between the concrete surrounding the steel anchorage box and this steel box can be successfully developed. Consequently, the steel-concrete composite anchorage system illustrated an excellent mechanical response and high reliability.

• Smart Structures and Systems
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• v.9 no.6
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• pp.489-504
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• 2012

For the safety of prestressed structures such as cable-stayed bridges and prestressed concrete bridges, it is very important to ensure the prestress force of cable or tendon. The loss of prestress force could significantly reduce load carrying capacity of the structure and even result in structural collapse. The objective of this study is to present a smart PZT-interface for wireless impedance-based prestress-loss monitoring in tendon-anchorage connection. Firstly, a smart PZT-interface is newly designed for sensitively monitoring of electro-mechanical impedance changes in tendon-anchorage subsystem. To analyze the effect of prestress force, an analytical model of tendon-anchorage is described regarding to the relationship between prestress force and structural parameters of the anchorage contact region. Based on the analytical model, an impedance-based method for monitoring of prestress-loss is conducted using the impedance-sensitive PZT-interface. Secondly, wireless impedance sensor node working on Imote2 platforms, which is interacted with the smart PZT-interface, is outlined. Finally, experiment on a lab-scale tendon-anchorage of a prestressed concrete girder is conducted to evaluate the performance of the smart PZT-interface along with the wireless impedance sensor node on prestress-loss detection. Frequency shift and cross correlation deviation of impedance signature are utilized to estimate impedance variation due to prestress-loss.