• Proceedings of the Korean Geotechical Society Conference
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• 1998.03a
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• pp.159-172
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• 1998

• Proceedings of the Korean Geotechical Society Conference
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• 2001.03a
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• pp.323-330
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• 2001

The existing bonding methods of steel pipe piles into pile caps have many problems during construction or design. To overcome these, the composite bonding method of the bolting type and the welding type are proposed in this stud\ulcorner. The full scale test and the numerical analysis using finite element method were performed to verify the function of them. As results, the method of the filled with concrete in steel pipe piles head was good effective to increse strength. And the composite bonding methods are effective to protect the damage caused by earthquake than the bolted bonding method. Also, the composite bonding methods are cheaper than the existing bonding methods and a good construction as well.

• Geotechnical Engineering
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• v.14 no.6
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• pp.57-71
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• 1998

Present bonding methods which connect steel pipe and spread footing in pile foundation have been generally used. These methods however showed lots of difficulties in the quality control. A new bonding method, which is called 'Bolted Bonding Method(BBM)' , is developed. This method uses factory-made parts so that it may increase the degree of quality, and workability, and is being adopted in the Held concerned. The method is verified by the structural analysis and laboratory test and then a new design formula is proposed. In addition, a comparison test of the present methods and BBM are conducted to observe the applicability and economy of the latter. As results, it is observed that BBM shows 5 to 10 times faster in Held work and 9% to 50% cheaper in construction cost than the existing methods.

• Journal of the Korean GEO-environmental Society
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• v.8 no.3
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• pp.41-49
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• 2007

The typical bonding methods which connect steel pipe pile and spread footing is bolted bonding method using +type cover plate for reinforcing a head of steel pipe pile. In this paper, stability of spread footing in pile foundation have been evaluated by loading test of +type cover plate for reinforcing a head of pile and hook type bonding method. The presents results from a series of pilot model test on vertically loaded piles foundation of bolted bonding method and hook type bonding method, pile foundation is identified to safety due to pile foundation exceed 8.5~21% which more than yield stress of steel pipe pile. As the results of horizontal loading tests, peak load of piles foundation of hook type bonding method has estimated in 41.1tonf and it was exceed about 33% which more than pile foundation of bolted bonding method.

• Journal of the Korean Society of Industry Convergence
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• v.9 no.3
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• pp.183-190
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• 2006

Generally, application of steel pile as deep foundation member needs specials requirement for the connection method between steel pipe and concrete footing. To investigate real compressive behavior of connection member between steel pipe pile and concrete footing, three specimens were tested with carefully designed experimental system. Main test variable is the connection method between steel pipe pile and concrete footing. The bolted bonding method and hook bonding method was considered as the connection method in this study. From the test results gained from experiment, it was conformed that two types of connection method have the almost same compressive resistance capacity. Therefore, we can conclude that these two connection methods can be used as the strengthening method to verify the compressive composite action of concrete and steel pipe pile.

• Structural Monitoring and Maintenance
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• v.4 no.3
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• pp.237-253
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• 2017

Among various structural health monitoring technologies, impedance-based damage detection has been recognized as a promising tool for diagnosing critical members of civil structures. Since the piezoelectric transducers used in the impedance-based technique should be bonded to the surface of the structure using bonding layers (e.g., epoxy layer), it is hard to maintain the as-built condition of the bonding layers and to reconfigure the devices if needed. This study presents an experimental investigation by using magnetically attached PZT-interface for the impedance-based damage detection in bolted girder connections. Firstly, the principle of the impedance-based damage detection via the PZT-interface device is outlined. Secondly, a PZT-interface attachment method in which permanent magnets are used to replace the conventional bonding layers is proposed. Finally, the use of the magnetic attraction for the PZT-interface is experimentally evaluated via detecting the bolt-loosening events in a bolted girder connection. Also, the sensitivity of impedance signatures obtained from the PZT-interface is analyzed with regard to the interface's material.

• Proceedings of the Korean Society For Composite Materials Conference
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• 2005.11a
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• pp.57-60
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• 2005

Composite-to-aluminum joins were tested to get failure loads and modes for three types of joins; adhesive bonding, bolt fastening, and adhesive-bolt hybrid joining. Film type adhesive FM73 and paste type adhesive Cytec EA9394S were used for aluminum and composite bonding to make a double-lap joint. A digital microscope camcorder was used to monitor the failure initiation and propagation. It was found that the hybrid joining is an effective method to strengthen the joint when the mechanical fastening is stronger than the bonding as in the case of using the paste type adhesive. On the contrary, when the strength of the bolted joint is lower than the strength of the bonded joint as in the joint with the film type adhesive, the bolt joining contribute little to the hybrid joint strength.

• Steel and Composite Structures
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• v.23 no.4
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• pp.385-397
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• 2017

Currently, CFRP (Carbon Fiber Reinforced Polymer) plate bonding is used quite extensively as a strengthening method. In this technique, a composite CFRP plate or sheet of relatively small thickness is bonded with an adhesion material to steel or concrete structure in order to improve its structural behavior and strength. The sheets or plates do not require much space and give a composite action between the adherents. In this study, the rotation capacity of CFRP-strengthened cold-formed steel (CFS) beams has been evaluated through numerical investigation. Studies on different structural levels have been performed. At the beam level, C-section has been adopted with different values of profile thickness, web height, and flange width. At the connection level, a web bolted moment resistant type of connection using through plate has been adopted. In web-bolted connections without CFRP strengthening, premature web buckling results in early loss of strength. Hence, CFRP sheets and plates with different mechanical properties and geometric configurations have been examined to delay web and flange buckling and to produce relatively high moment strength and rotation capacity. The numerical results reveal that CFRP strengthening may increase strength, initial stiffness, and rotation capacity when compared with the case without strengthening.

• Journal of the Korea institute for structural maintenance and inspection
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• v.12 no.1
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• pp.91-100
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• 2008

Multi-stepwise Thermal Prestressing Method(TPSM) is a newly proposed prestressing method, which is combined the external prestressing method and the external bonding method. Multi-stepwise thermal prestressing force is induced by cooling process of cover-plate in the multi-stepwise temperature distribution after the cover-plate being bolted to the girder. In this study, the heating capacity test of the developed heating system for applying the multi-stepwise TPSM effectively and multi-stepwise TPSM inducing test of H-beam is performed. Also, a field test of the rhamen type temporary bridge is carried out to evaluate the effect and application of the multi-stepwise TPSM. Truck load was loaded and compared with the structure analysis results.

• Journal of the Microelectronics and Packaging Society
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• v.25 no.2
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• pp.9-17
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• 2018

Aluminum (Al) and its alloys have been used widely in a variety of industries such as structural, electronic, aerospace, and particularly automotive industries due to their lightweight characteristic, outstanding ductility, formability, high oxidation and corrosion resistance, and high thermal and electrical conductivity. Al have different kinds of alloys according to the various additional elements system and they should be selected properly depending on their effectiveness and suitability for their particular purpose. The major elements for Al alloys are silicon (Si), magnesium (Mg), manganese (Mn), copper (Cu), and zinc (Zn). In order for Al alloys to use for each industry, it is necessary to study of Al to Al joining and/or the Al to dissimilar materials joining to combine the individual parts into one. Many studies on joining technologies about Al to Al and Al to dissimilar materials have been performed such as press joining, bolted joint, welding, soldering, riveting, adhesive bonding, and brazing. This study reviews a variety of Al alloys and their joining method including its principles and properties with recent trends.