• 콘크리트학회논문집
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• 제11권5호
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• pp.107-118
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• 1999

10 RC bridge piers have been made on a 1/3.4 scale model, and six piers of them were retrofitted with glassfiber. The have been tested in the quasi-static cyclic load so as to investigate their seismic enhancement before and after retrofitting with glassfibers. The objective of this experimental study is to investigate how to strength the ductility of reinforced concrete bridge piers which have been nonseismically designed and constructed in Korea before 1992. Important test parameters are axial load, load pattern, retrofit type. Glassfiber sheets were used for retrofitting in the plastic hinge region of concrete piers. The nonlinear behavior of bridge columns have been evaluated through their yield and ultimate strength, energy dissipation, displacement ductility and load-deflection characteristics under quasi-static cyclic loads. It can be concluded from the test that concrete piers strengthened with glassfibers have been enhanced for their ductile behavior by approximate 50%.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2000년도 가을 학술발표회논문집(I)
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• pp.785-792
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• 2000

Repair and retrofit system of concrete structures has been developed from conventional reinforced concrete overlaying, steel plate bonding and recently to fiber composite systems. Research and study on carbon, aramid, and glass fiber composite system has been actively carried out from all over the world Glass fiber composite is proved to be competitive technically and enconomically, among fiber composite system. CAF system is a system developed locally using all domestic materal, glass fabric and epoxy, and improved in shear bonding property by utilizing silica fume mixed with epoxy. All the tests on material properties, structural behavior, constructiveness at site and quality control procedure proved to be most appropriate system so far developed. Futher research work is and will be under progress for utilization of this system which will be applied to more adverse situation.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2000년도 봄 학술발표회 논문집
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• pp.751-756
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• 2000

The structural behavior of reinforced concrete slabs strengthened by glass fiber reinforced plastic-panels experimentally investigated. The experimental variables are strengthening length, strengthening width, and pre-crack existence. The pre-cracked slabs are initially loaded to 70 percent of ultimate flexural capacity and subsequently repaired with GFRP-Panels bonded to the tension face of the slabs. Five one-way slabs were tested to failure. The main failure mode of strengthened slabs is separation failure by crack propagation from load point section to end of plate. The behavior of strengthened slabs is represented by a maximum load, load-deflection curves an load-strain curves.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1998년도 가을 학술발표대회 논문집(III)
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• pp.815-820
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• 1998

Many composite girder bridges have been constructed for about thirty five years. Nowadays they are aged or deteriorated because of th increase in traffic and vehicle loads. In this study, the effect of strengthening with glass fiber sheet is investigated to estimate the possibility for appling for damaged prestressed concrete bridges. One normal and eight cracked specimens which had been preloaded were tested. The cracked specimens were strengthened with either external prestressing or bonding glass fiber sheet, or using both methods. The results showed that the maximum loads are almost same for both methods. So it seems that the strengthening with glass fiber sheet can be used for strengthening damaged prestressed concrete girders. It is important that proper devices should be selected to prevent glass fiber sheet from premature bonding failure below its maximum load, which is similar to end anchorage problem in external prestressing method. It is proved that the devices proposed in this paper have sufficient anchoring capability to increase load carrying capacity.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1997년도 봄 학술발표회 논문집
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• pp.669-675
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• 1997

This paper investigates the performances of GFRP bar and its possibility for using a substitute of steel bar. GFRO bar was made with introducing the glass fiber into GTR added UPE. We carried out the tensile test of GFRP and steel bar and out the three point bend test bond-test and fracture energy measurement on the GFRP bar and steel bar reinforced concrete. The GFRP bar was excellent as comparison with steel bar in the contribution to the energy absorption and the ductility of concrete. But its tensile, bond and bend strengthes were comparatively small. In order to improve these defects, we judged that glass fibers in GFRP bar must be completely adhesive one another by the impregnating glass fibers into UPE.

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 2010년도 정기 학술대회
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• pp.484-487
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• 2010

본 논문에서는 BIM(Building Information Modeling)의 핵심기술인 파라메트릭 기술을 기반으로 하여 철근콘크리트 구조물의 기둥부재 주철근 자동배근시스템을 구축함으로써 기존 프로그램에서 사용자가 직접 입력해야하는 변수의 수를 최소화하고 사용성과 정확성을 높이는 것을 목적으로 한다. 기존 철근배근 형상 자동 모델링에서 기둥철근의 자동 모델링은 기둥단면이 변하는 부분에서의 철근 배근과 정착 및 이음길이를 고려하지 않고 있다. 만약 고려하더라도 이용자가 직접 입력하는 방식이기 때문에 규모가 큰 건물일 경우 방대한 정보의 처리 미숙으로 인해 정확한 모델링을 기대하기 어려운 실정이다. 본 연구에서는 기둥 부재에 대하여 대상 건물을 선정하고 구조해석 모델링을 구축한 후 구조해석 결과 데이터베이스를 추출하여 얻은 정보와 건축구조설계기준에 따른 정착 및 이음 길이 산정에 관한 알고리즘을 구축하여 철근배근 형상 자동화 모듈에 적용하여 배근 자동 설계 및 자동 형상화 모듈을 생성하였다.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2005년도 춘계 학술기술논문발표대회 논문집
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• pp.93-98
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• 2005

The purpose of this study was to analyze the compression strength research by aerated concrete as mixing ratio This Study used foaming-agent and produced aerated concrete by pre-foam way that is used in construction site. An experiment changes unit cement amount, w/c and the glass fiber mixing rate and 'measured capacity change, unit capacity weight and compressive strength. The results obtained from experimental study are as following; Research to reduce unit capacity weight in condition more than unit cement amount 500kgf is considered should be gone side by side. The highest compressive strength result appeared in aerated concrete that cement amount 600kgf and w/c ratio $45\%$, $50\%$. compressive strength was increased maximum $34%$ when glass fiber $0.7\%$ addition cause by coherence enlargement to enlargement of cement paste and glass fiber addition per unit volume

• 한국소음진동공학회논문집
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• 제23권5호
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• pp.414-422
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• 2013

As structure-borne sound, the floor impact sound is one of the serious noises in residential building. Most of heating system applied to the typical Korean residential building is floor heating system which is called ondol. The ondol usually consists of finishing material, mortar with heating coil, light-weight aerated concrete and reinforced concrete. This study focused on the isolation of heavy-weight impact sound and modification of mortar and light-weight aerated concrete. Specifically the glass foam aggregate was added on light-weight aerated concrete. Also, water-cement ratio and amount of cement on mortar were revised. The sound pressure level of heavy-weight impact was measured in reverberation chamber using both bang-machine and impact ball. The size of specimen was 1 m by 1 m. Substitution ratio of glass foam aggregate on light-weight aerated concrete shows relationship with heavy-weight impact sound pressure level. In addition, heavy-weight impact sound pressure level was decreased with increment of water-cement ratio and amount of cement on mortar.

• 한국해양환경ㆍ에너지학회지
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• 제12권1호
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• pp.29-34
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• 2009

FRP선박의 폐처리와 재활용 연구는 지난 10여 년간 많은 발전이 이루어져 왔다. 특히 해상용과는 달리 폐기물의 투기나 방치가 매우 어려운 육상용 폐FRP의 재활용 방법과 기술의 발전에 기인한 결과이기도하다. 따라서 가장 많은 폐FRP 선박의 재처리는 육상용의 처리공정, 즉 파쇄와 분쇄 공정을 거친 후 수지류와 유리섬유류로 분리하여 재활용 또는 지정폐기물로 처리하게 되었다. 지난 연구를 통하여 처리공정 운영 측면에서 보다 경제적이며 2차 처리공정(분쇄 후 공정)에 유용한 시스템을 개발하였다. 그러나 다년간의 실험실규모의 처리시스템 운영을 통하여 두 가지의 개선점이 발견되었다. 첫째는 단순 용융하여 활용하던 유리섬유의 형상(폭과 넓이)의 다양화가 필요하게 되었으며, 두 번째 문제로는 수중 파쇄 공정 도입을 통하여 분진을 억제하였으나 시스템 상부(파쇄전 공정)를 통한 분진유발로 인하여 작업성의 저하가 발생한다는 것이다. 우선 유리섬유의 형상변화는 파쇄공정 중 칼날의 변화를 통하여 섬유 형태뿐만 아니라 chip형태(직사각형)로 박리할 수 있게 되었으며 파쇄공정의 상부에 cyclone분류기를 설치하여 유리가루와 수지가루를 분류하여 재활용하게 되었다. 아울러 작업환경의 청정성도 유지하게 되었다. 또한 유리 chip을 활용한 노 콘크리트 제품의 강도 실험결과 매우 우수한 결과를 보여주고 있으므로 앞으로의 폐FRP 선박의 재활용 분야의 다양성을 기대할 수 있을 것이다.

• 대한토목학회논문집
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• 제37권2호
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• pp.269-276
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• 2017

본 연구는 철근콘크리트구조를 대신할 FRP-콘크리트 합성구조의 극한 휨 거동에 관한 것으로, FRP-콘크리트 합성보의 구조적 성능 및 거동 특성을 수치 해석적으로 규명하고자 범용 해석프로그램인 ABAQUS를 사용하여 외연적 비선형 유한요소해석을 실시하고 기 수행한 실험과 비교분석하였다. 콘크리트의 재료모델은 콘크리트 손상 소성모델을 사용하였으며, 콘크리트 압축응력은 유로코드를 사용하였다. 4가지 종류의 FRP-콘크리트 합성보에 대해 비선형해석을 수행하고 극한하중 및 균열 형태를 비교 분석하였다. 본 모델의 경우 극한 하중 및 균열 형태를 잘 모사할 수 있었기 때문에 앞으로 다양한 FRP-콘크리트 합성구조의 정밀한 구조거동 해석 및 분석에 사용 가능할 것으로 판단된다.