This paper presented to study used Abaqus on steel plate bonded reinforcement technology for column to beam connections, and then the result showed that steel plate bonded reinforcement technology has great reinforcement effect for RC column to beam joint. Also the steel plate bonded reinforcement technology was safety and convenient operation.

This study is to determine the flexural reinforcement performance of the RC beam through the NSM reinforcement experiment. To do this, to produce non-reinforced specimen and reinforced specimens were performed the experimental study. As the results of this study, the tension reinforcing steel has been confirmed between the FRP bar and filled material integrated behavior before yielding. Compared with non-reinforced specimen the reinforced specimens showed that the rigidity of the reinforced specimens is higher than that of the non-reinforced specimen about 16.7%, and increases 8.3%~20.0% and 33.3%~52.7% for yielding strength and ultimate strength respectively. It appears an excellent bending reinforcing effect.

본 연구에서는 FRP로 보강된 장방형 철근콘크리트 기둥의 구속효과에 미치는 형상계수의 영향력 평가를 수행하였다. Lam and Teng의 연구결과를 바탕으로, FRP 종류를 구분하고, 단면형태에 따라 총 150여개의 철근콘크리트 기둥 실험 데이터를 분석하였다. 분석 결과, 단면의 형상계수가 구속효과에 가장 큰 영향을 미치는 것으로 나타났으며, FRP로 보강된 장방형 철근콘크리트 기둥은 보강되지 않은 철근콘크리트기둥에 비하여 구속효과가 28%에서 67%까지 증가되는 결과를 나타냈다. 또한, 정방형 형태는 장방형 형태에 비하여 약 20% 정도 증가되는 구속효과가 나타남을 확인할 수 있었다. 현재 FRP 보강에 대한 구속효과 산정식은 매우 복잡한 형태를 보이고 있으며, 실무에 적용하기 어려운 실정이다. 이에 본 연구에서는 분석한 결과를 이용하여, 간단한 구속효과 산정식을 제안하였다.

Hokenberry and Lopez (2012) and Aoude et al. (2012) have shown that the steel fiber can be a substitute of the stirrup for shear strengthening. In this study, Vector 2 program which takes into account modified compression field theory tensile softening behaviors of SFRC were used for prediction of the shear capacities of SFRC beams.

The purpose of this study is to evaluate a RCS strengthening method for medium & low-rise R/C buildings using the nonlinear analyses of member-level. In this study, a three-story R/C buildings that represents a typical Korean school constructed in the 1980s was selected. Seismic capacities of the building before and after CFCC strengthening method are evaluated using the nonlinear static & dynamic analyses of member-level.

본 연구에서는 1992년 도로교설계기준의 내진설계도입 이전 규정에 따라 설계, 시공된 교각의 축소 모델을 실험체로 제작하여 원형기둥의 변위비에 따른 횡하중을 변위제어 방식으로 입력하여 준정적 방법을 통해 실험을 실시하였다. 연구에 적용한 보강재는 성능을 향상시킨무기계 합금강인 Helical Bar로써 원형기둥 외부에 보강 후 실내실험을 통하여 파괴거동, 하중-변위 관계, 연성도 평가 및 에너지 평가를실시하였다. 실험변수로는 위험단면 내에서 나선으로 보강한 보강재의 단면력의 크기와 나선보강의 간격, 보강형태로 두었으며, 준정적 실험을 통해 보강성능의 차이와 효과를 확인하였다. 실험결과 보강대상 부재의 성능에 따라 적절한 보강재의 단면력 크기결정과 보강간격 및형식의 선정이 필요하며 기계적 보강재뿐만 아니라 고강도 콘크리트 피복으로의 치환으로도 보강성능이 향상됨을 확인할 수 있었다.

To evaluate the aramid sheet and metallic damper strengthening effect of non-seismic detailed RC frame FE program, which is ABAQUS, analysis is used. Used material model of concrete, steel, rebar and aramid are concrete damaged plasticity model, steel plasticity model, perfectly plasticity model and linear fracture model, respectively. From step by step lateral load increment, the stress and crack distribution of frame and elements can be properly simulate by FE analysis.

This study is about earthquake-proof reinforcement through structural function evaluation of an existing structure. The purpose of this study is to comparatively analyze structure reinforcement measures in consideration of safety and usability through structural function evaluation of existing structures, to offer rational measures for earthquake-proof function and to provide help in maintaining safe structures against earthquake. For this purpose, was selected for this study as an existing school building, earthquake-proof function evaluation was conducted, and measures to reinforce earthquake-proof function was offered. As for the research method, the first and the second earthquake-proof function evaluations were conducted which is an existing reinforced concrete school building. Through the abovementioned methods, earthquake-proof function evaluations were conducted, the results were analyzed and the measure to reinforce earthquake-proof function were offered(reinforcement brace, RC shear wall reinforcement). The offered measure to reinforce earthquake-proof function was applied to the subject structure, and comprehensive results were derived from earthquake-proof function evaluation regarding before and after earthquake-proof function reinforcement.

The purpose of this study is to evaluate a RCS strengthening method for medium & low-rise R/C buildings using the nonlinear analyses of member levels. In this study, a three-story R/C buildings that represents a typical Korean school building constructed in the 1980s was selected. Seismic capacities of the building before and after strengthening with the RCS method are evaluated using the nonlinear static & dynamic analyses of member levels.

The purpose of this paper is to verify the seismic strengthening effect of R/C buildings strengthened with the Carbon Fiber Composite Cable (CFCC) In this study, a three-story R/C building that constructed in the 1980s was selected, and its seismic performance before and after strengthening was evaluated based on the nonlinear dynamic analyses of members levels. The result indicated that the seismic strengthening effect of the proposed CFCC method was verified in terms of both strength and ductility demands, compared to the building before strengthening.

On this study, the laboratory model test is a soil tanker to be contained with clay and grid form improved soil, the test model is conducted in total 9case with the uniaxial compressive strength of improved soil and replacement ratio of improved soil. Numerical analysis for variation of stress distribution ratio with depth is performed in the same conditions which are the laboratory model test. As a result, stress distribution ratios in mid and high replacement ratio are increasing and settlement is decreasing, except low replacement ratio. This study is presented for form effect ratio and settlement reduction factor with change of structure form, it is able to be helpful in further research and reference for change of structural forms at composite ground.

In this study, experimental research was carried out to evaluate and improve the constructability and structural performance of high strength R/C interior beam-column joints regions, with or without the shear reinforcement, using high ductile fiber-reinforced mortar. Specimens designed by retrofitting the interior beam-column joint regions of existing reinforced concrete building showed a stable mode of failure and an increase in load-carrying capacity due to the effect of enhancing dispersion of crack control at the time of initial loading and bridging of fiber from retrofitting new high ductile materials during testing.

The purpose of this study is to verify a RCS strengthening method for Medium & Low-rise R/C buildings using the nonlinear analysis. In this study, a three-story R/C building that represents a typical Korean school constructed in the 1980s was selected. Seismic capacities of the building before and after RCS strengthening are evaluated based on the nonlinear static and dynamic analyses.

The purpose of this paper is to verify the seismic strengthening effect of R/C buildings strengthened with the Carbon Fiber Composite Cable(CFCC). In this study, a three-story R/C building that represents a typical Korean school constructed in the 1980s was selected, and its seismic performance before and after strengthening was evaluated based on the nonlinear dynamic analyses. The result indicated that the seismic strengthening effect of the proposed CFCC method was verified in terms of both strength and ductility demands, compared to the building before strengthening

Korea is a peninsula which has a lot of soft ground including coastal areas. This soft ground is consisted of clay or silt and it generally has features of high compressibility. Therefore, in order to build a structure, high compressibility ground is needed carrying out ground improvement using deep cement-mixing method. As a Fig 1, this study is evaluated for the applicability of which are load sharing ratio, stress distribution ratio, pore water pressure and settlement with grid structure form

This study presents the seismic evaluation and prediction of post-retrofitted piloti-type reinforced concrete building with buckling-restrained braces (BRBs) under the successive earthquakes. For seismic assessment before and after retrofit of the BRBs, the fragility analysis is considered. The fragility relationships for the damaged building between ground shaking intensity and damage probability were derived under the successive earthquakes.

폴리프로필렌섬유보강 시멘트 복합재료와 구조용 합성섬유의 부착특성을 평가하였다. 폴리프로필렌섬유는 0.10%, 0.15% 및 0.20%의 체적비로 적용하여 dog-bone 시험을 실시하였다. 구조용 합성섬유와 폴리프로필렌섬유보강 시멘트 복합재료 사이의 부착강도는 폴리프로필렌섬유의 혼입률이 증가할수록 증가하였으나 0.20% 이상이 되면 감소하였다. 또한 폴리프로필렌섬유의 첨가는 계면인성과 마찰저항을 증가시킨다. 인발시험 후 구조용 합성섬유 표면의 미소구조 분석은 폴리프로필렌섬유의 혼입률이 증가할수록 긁힘 현상이 증가하였다.

최근 세계 곳곳에서 대규모 지진이 발생하여 건축물 붕괴에 따른 피해가 속출함에 따라 지진에 대비하기 위해 기존 건축물의 내진 성능을 보강방안에 대한 관심이 높아지고 있다. 그러나 현재 우리나라의 경우, 교육생활의 터전임과 동시에 가구 재난 발생 시 지역주민들의 응급피난장소인 학교 건축물조차 내진설계가 제대로 이루어져 있지 않고 있어, 지진 발생 시 막대한 피해가 예상된다. 현 상황을 극복하기 위해 기존 노후화 학교 건축물의 내진성능을 향상시키기 위한 적절한 보강방안이 제시되어야한다. 본 논문에서는 범용해석프로그램을 통해 기존 노후화 학교 건축물에 대한 비선형정적해석에 결과에 따른 내진보강 후 비선형 시간이력해석을 실시하여 지진하중에 의한 구조물의 비선형 거동을 규명하고 내진 보강 효과를 검증하고자 한다.

도시 면적의 많은 부분을 차지하고 도로포장면은 불투수성으로 비가 오면 빗물이 배수구를 통해 신속히 배수됨으로써 도시 홍수 발생, 지하수위의 저하와 용수의 고갈 등 생태계의 불균형을 초래하고 있으며 도시지역의 열섬현상과 같은 환경문제를 발생시키고 있다. 도시부에서 발생되는 이러한 문제를 해결하기 위한 방안으로 투수성포장이 적용되고 있으나 우수 침투로 노상이 연약화 될 것을 우려하여 차도에는 적용하지 못하고 있는 실정이며 중량이 가벼운 차량이 통과하는 광장, 주차장 및 보도, 자전거 포장에 투수성포장이 이용되고 있다. 차도에 투수성포장을 적용하기 위한 방안으로 투수성포장 하부 층에 연약지반 보강 공법으로 활용되고 있는 지오셀 두께 1.2㎜, 1.5㎜, 깊이 12㎝를 적용하여 지지력을 측정한 결과 두께 1.2㎜ 지오셀은 측정 위치에 따라 상이한 결과를 나타내었으며, 두께 1.5㎜ 지오셀은 보강 효과가 있는 것으로 나타났다. 특히 재하하중이 크면 클수록 그 효과는 더 큰 것으로 평가되었다.

최근 국내에서도 지진의 발생 가능성이 증가하는 추세이며 교량 및 터널 등의 시설물에 대한 지진과 같은 예상하지 못한 작용하중에 대한 안전성을 강화하고 있다. 특히, 1988년 이전 건설된 도시철도 시설물의 대부분은 내진설계가 반영되지 않아 지진하중에 대해 취약할 수 있으므로, 내진안전성에 대한 검토와 보강이 요구되고 있다. 이 연구에서는 도시철도 개착식 터널의 내진성능 향상을 도모하고자, 구조적 취약부분인 내측 기둥에 내진보강을 위한 새로운 FRP-연성재 적층복합체를 제안하였다. 적층조건에 따른 FRP-연성재 적층복합체에 대한 실험을 통해 재료물성치를 산출하여, 이를 근간으로 수치모델을 작성하였다. 수치해석을 통해 제안된 보강재로 보강된 RC기둥의 내진성능이 증대됨을 알 수 있었다. 또한 섬유보강재의 적층조건 (연성재의 종류, FRP 적층수, 섬유배향각)에 따라 성능 향상의 차이가 있는 것을 확인할 수 있었다.