• 대한기계학회논문집A
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• 제25권12호
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• pp.1981-1987
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• 2001

This paper documents the effect of surface treatment of aluminum on the bonding strength of aluminum/CFRP composites. The surface of aluminum panel was treated by DC plasma. The optimal treatment condition of the aluminum was determined by measuring the contact angle and T-peel strength as functions of mixture ratio of acetylene gas to nitrogen gas. The mixture ratios used were 1:9, 3:7, 5:5, 7:3, and 9:1 Lap shear tests and T-peel tests were performed using surface-treated alumiunm/CFRP composites and regular alumiunm/CFRP composites. The results showed that the contact angle was minimized and the T-peel strength was maximized iota the mixture ratio of 5:5. The results also showed that the shear strength of surface-treated alumiunm/CFRP composites was 34% greater than that of regular alumiunm/CFRP composites. The T-peel strength of surface-treated alumiunm/CFRP composites was also 5 times greater than that of regular alumiunm/CFRP composites.

• 대한용접접합학회:학술대회논문집
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• 대한용접접합학회 2007년 추계학술발표대회 개요집
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• pp.26-28
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• 2007

This research is concerned with a study of failure strength evaluation on heat element gap at resistance welding. The failure strength of resistance welded joint is changed by welding factor like as current(power level), welding time(total energy), pressure etc. and another heat element factor like as number of element line, element gap etc. Tensile-shear tests were carried out with the single-lap specimen using polypropylene(PP). The failure mechanism and optimization of gap was discussed in order to explain the tensile-shear strength evaluation on heat element gap at resistance welding. Orthogonal array was used by fractional factorial design for efficient experiments.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1997년도 가을 학술발표회 논문집
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• pp.653-658
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• 1997

Recently, carbon Fiber sheet (CFS) is frequently used for strengthening deteriorated concrete structures. To strengthening damaged structures, the property and characteristic of the bond between CFS and the concrete surface must be understood. The tensile test of single lap shear specimen was performed to study bond strength, bond stress distribution and stress transfer between CFS and concrete surface according to the bond length. Based on the test results, there were ultimate influence length (UIL) in which bond stress was distributed, and ultimate strain reduction ratio (USRR) by which strain was reduced linearly. Bond resisting force (BRF) was estimated by UIL and USRR, and which was compared with ultimate loads. According to the results of comparison, it was shown that ultimate bond strength could be estimated reasonablely by BRF.

• 한국터널지하공간학회 논문집
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• 제13권3호
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• pp.277-289
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• 2011

본 연구에서는 압축력을 받는 터널 라이닝 부재 특성에 보다 부합된 조건에서 FRP-콘크리트 접촉면의 전단 저항력을 평가할 수 있는 새로운 시험법을 제안하였으며, 제안 시험법은 기존 시험방법에 비해 시험체 제작과 시험방법이 매우 용이하다. 제안된 시험법을 기반으로 FRP와 콘크리트 복합소재의 전단저항성능을 좌우하는 규사코팅의 최적조건을 도출하기 위한 매개변수 연구를 실시하였다. 다양한 시료에 대한 시험결과를 기존 연구결과와의 비교분석을 통하여 제안 시험법의 타당성을 보였으며, FRP부재와 콘크리트 접촉면의 전단저항을 극대화 시킬 수 있는 효과적인 규사입경 및 밀도에 대한 최적 조건을 제시하였다.