• Proceedings of the Earthquake Engineering Society of Korea Conference
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• 2000.10a
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• pp.296-303
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• 2000

The purpose of this study is to find inelastic behavior and ductility capacity of reinforced concrete bridge columns under earthquake. Material nonlinearity is taken into account by comprising tensile, compressive and shear models of cracked concrete and a model of reinforcing steel. The smeared crack approach is incorporated. In boundary plane at which each member with different thickness is connected, due to the abrupt change in their stiffness local discontinuous deformation can be taken into account by introducing interface element. Also an analytical model is developed to express the confining effects of lateral tie which depend on the existence or nonexistence and the amounts of transverse confinement, etc. The proposed numerical method for inelastic behavior and ductility capacity of reinforced concrete bridge columns will be verified by comparison with reliable experimental results.

• Proceedings of the Korea Concrete Institute Conference
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• 1998.10a
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• pp.501-506
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• 1998

This paper is an experimental study on the flexural strength and ductility capacity of reinforced high performance concrete beams with the concrete which has compressive strength of 600~700kg/$\textrm{cm}^2$, slump value of 20~25cm and slump-flow value of 60~70cm. Total 8 beams with different tensile reinforcement ratio and pattern of loading were tested. Form the results of reinforced high performance concrete beams, the equivalent stress block parameters proposed by MacGregor et al. or New Zealand code are recommended to use. Also, an extreme fiber concrete compressive strain of reinforced high performance concrete beams are distributed 0.0033~0.0048. In reinforced high performance concrete beams, reinforcement ratio in order to insure curvature ductility index 2 and 4 propose by ACI code should be less than those of reinforced normal strength concrete beams.

• Magazine of the Korea Concrete Institute
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• v.10 no.2
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• pp.119-126
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• 1998

본 연구는 철근비와 보강판비를 조정한 보강철근비를 변수로 탄소섬유쉬트 접착된 철근콘크리트 보에 대하여 그 변형특성과 강도특성 및 파괴모드를 실험적으로 고찰한 것이다. 철근비와 보강판비가 증가할수록 최대내력은 증가하는 경향을 보이지만 탄소섬유쉬트의 겹수가 증가할수록 철근비 증가의 경우와는 달리 에너지흡수능력이 저하된다. 철근비와 보강판비에 따른 파괴모드를 구분하고 시험결과와 비교, 고찰하였던 바 파괴모드와 연성의 측면에서 보강철근비 е의 한계값을 0.87 max으로 제안하였다．탄소섬유쉬트와 철근콘크리트 보의 합성작용이 철근항복이후까지 유지되어 비선형적인 거동을 보임으로써 구조적거동이 양호하게 나타나는 것으로 입증되었다.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.11 no.10
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• pp.4024-4030
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• 2010

Axial load tests and cyclic load tests for FRP reinforced rectangular CFT columns were carried out The main parameters were width-thickness ratio of a steel tubeand FRP layer numbers for the axial load tests and were concrete strength and FRP layer numbers for cyclic load tests. The maximum strength and ductility capacity were compared between the current CFT columns and the FRP reinforced CFT columns. Finally, the axial design formulas were presented for the FRP reinforced CFT columns.

• Proceedings of the Korea Concrete Institute Conference
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• 2002.05a
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• pp.879-884
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• 2002

The objective of this study is to investigate the seismic capacity of the non-seismically detailed RC bridge piers before and after applying a seismic retrofitting method using stainless steel wire mesh. Total nine circular section RC piers were constructed. Different lap splice longitudinal reinforcement details were adapted for four specimens and various types of stainless steel wire mesh were applied for the remaining five specimens. Harmonic cyclic lateral load was applied on each specimen under a constant axial load. The test results indicated that the existing circular piers have low seismic capacity while the stainless steel wire mesh retrofitting method improves the seismic capacity considerably. In addition, test results revealed that the circular section piers could have a considerable amount of ductility if longitudinal bars are not lap-spliced in potential plastic hinge zone. Based on this experimental study it could be concluded that the seismic performance, that is ductility and energy absorption capacity, of the non-seismically detailed RC bridge piers would be increased by applying the stainless steel wire mesh seismic retrofitting method.

• Magazine of the Korea Concrete Institute
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• v.2 no.4
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• pp.53-60
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• 1990

Investigations on the behavior of steel fiber reinforced high strength concrete beams with shear confinement are accomplished to determine their ultimate shear strength including diagonal tension strength. The parameters varied were the shear confinement ratio(Ps), and fiber volume fraction(Vs). Ultimate shear strength increased significantly in steel fiber reinforced concrete beam without shear confinement. In steel- fiber reinforced high strength concrete beams with shear confinement, there is no increase of ultimate shear strength but shows much beneficial effects of Ductility Capacity.

• Proceedings of the Korea Concrete Institute Conference
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• 2009.05a
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• pp.169-170
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• 2009

CFT structure has many advantages compared with the ordinary structural member made of steel or reinforced concrete. Because of increases in ductility, stiffness and load carrying capacity of overall structure owing to confinement effect of steel box and concrete, CFT structure is widely used to columns. Recently, the utilization of CFT member has been expanded to bridge structure as a girder member. The purpose of this study is to develop the analytical model and propose design method for CFTA girder bridge consisting of CFT structure, arch shape and tendons.

• Proceedings of the Korea Concrete Institute Conference
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• 2009.05a
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• pp.107-108
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• 2009

This is an experimental study on using the Honeycomb System show you the method of increasing ability of ductility and shear strength seismic performance to reinforced concrete column and masonry waist-high wall.

• Proceedings of the Korea Concrete Institute Conference
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• 2009.05a
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• pp.99-100
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• 2009

In this paper, wish to achieve an experimental study to investigate enhanced performance of the masonry walls strengthened in shear and ductility using Aramid fiber strip.

• Proceedings of the Korea Concrete Institute Conference
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• 2010.05a
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• pp.113-114
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• 2010

In this study, the earthquake damage evaluation of a R/C frame building is carried out based on the method proposed in Part I. Using the proposed method, the earthquake damage of building system based on non-linear required strength spectrum can be effectively evaluated without using the detailed seismic evaluation methods, including non-linear dynamic analyses, capacity spectrum method, etc.