• Magazine of the Korea Concrete Institute
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• v.7 no.6
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• pp.64-73
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• 1995

• Magazine of the Korea Concrete Institute
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• v.7 no.6
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• pp.74-91
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• 1995

• Magazine of the Korea Concrete Institute
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• v.27 no.1
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• pp.41-44
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• 2015

• Magazine of the Korea Concrete Institute
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• v.9 no.1
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• pp.29-35
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• 1997

• Proceedings of the Korea Concrete Institute Conference
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• 2006.05b
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• pp.325-328
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• 2006

Recently, repair mortars have been mainly used for repairing old concrete structures. In this study, a new repair mortar including shotcrete admixture, slag, silica fume, sulphate and calcium carbonate, was developed for repairing shotcrete layer and the fresh properties and mechanical characteristics of the repair mortar was measured, Test results showed that the shortcrete admixture and other additives reduce the final setting time from about 7 hours to within 20 minutes and increase very early strength and stiffness (within 5 hours after cast).

• Proceedings of the Korea Concrete Institute Conference
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• 1996.10a
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• pp.416-424
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• 1996

Reinforced Concrete structures need repair and rehabilitation due to the deterioration such as crack, spalling and disintegration. Numerous repair materials which are currently used in cinstruction fields witdout any specifications are examined in terms of their serviceabilities and effectiveness. In this paper sections of R/C beams are enlarged with repari material(epoxy, latex, premix), and then they are strengthened with rebar, steel plate of CFRP sheet on the tension side. Structural behaivior of strengthened beams are investigated under stactic tests and compared with each parameters.

• Proceedings of the Korea Concrete Institute Conference
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• 1996.10a
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• pp.546-550
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• 1996

The personal-computer software program named SAMS(Structural Aging Management System) was developed for the concrete structure of NPP(Nuclear Power Plant). SAMS is constituted of three part, detabase system containing various inspection data, operation program for standard input/output of the inspection data, and application program for efficient operation of database system. Using the SAMS, the field engineers can easily acquire the information about the various inspection data, repair and accidental histories of NPP structures. SAMS will contribute to the effcient maintenance of NPP structures.

• Composites Research
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• v.18 no.4
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• pp.66-74
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• 2005

This paper reports new repair and strengthening mathod using improved material. This mathod have two type according to covering thickness of reinforcement. One type is near surface mounted FRP rod. Anther type is overay. Fiber Reinforced Plastic (FRP) materials has become very popular in recent years. FRP material used to rehabilitate many types of structures with superior characteristics such as high strength and stiffness and corrosion resistance. This strengthening mathod were used FRP rod which have better bond and shear strangth than current FRP rod. Development of FRP rod due to 3-D winding system. In addition, Ductile hybrid FRP has a certain plastic deformation and an elongation greater than 3% at maximum load is usually required for steel reinforcement in concrete structures. Moerover this mathod can be effective repair of base concrete by sprayed polymer mortar.

• Proceedings of the Korea Concrete Institute Conference
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• 1999.04a
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• pp.813-818
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• 1999

The construction of large scale civil and building structures which form the base of social economy has been grown greatly. As the increasing of aged and deteriorated structures, it is necessary to evaluate the safety of those structures. The deterioration, safety evaluation, repair and rehabilitation are important problems in the construction area that every country faces. This paper presents the general information on how to conduct a data analysis of long-term monitoring system and evaluate the characteristics of surveying methods.

• Journal of Korean Association for Spatial Structures
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• v.23 no.2
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• pp.79-90
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• 2023

Existing reinforced concrete (RC) frame buildings have seismic vulnerabilities because of seismically deficient details. In particular, since cumulative damage caused by successive earthquakes causes serious damage, repair/retrofit rehabilitation studies for successive earthquakes are needed. This study investigates the repair effect of fiber-reinforced polymer jacketing system for the seismically-vulnerable building structures under successive earthquakes. The repair modeling method developed and validated from the previous study was implemented to the building models. Additionally, the main parameters of the FRP jacketing system were selected as the number of FRP layers associated with the confinement effects and the installation location. To define the repair effects of the FRP jacketing system with the main parameters, this study conducted nonlinear time-history analyses for the building structural models with the various repairing scenarios. Based on this investigation, the repair effects of the damaged building structures were significantly affected by the damage levels induced from the mainshocks regardless of the retrofit scenarios.