복합환경인자에 의한 FRP 보강근의 성능저하 특성
A Degradation Characteristic of FRP Rebars Attacked by Combined Environmental Factors
0
조회
0
다운로드
4
인용
0
참고문헌
키워드
초록
FRP 재료는 높은 부식저항성과 강도에도 불구하고 지난 20여년 동안 심각한 환경적 노출에 의한 재료의 성능저하에 대한 문제가 제기되어 왔다. 본 연구에서는 섬유와 수지로 구성된 이질재료인 FRP보강근이 온도와 화학적 노출을 복합적으로 받는 경우에 대하여 실험적으로 분석하였다. 각기 다른 형상으로 제작된 탄소, 유리 및 하이브리드 FRP 보강근 5종류에 대하여 중량변화, 계면전단강도(ILSS), SEM 및 FT-IR분석을 수행하였으며, 모든 FRP 실험편은 최대 150일까지 알칼리 용액과 증류수에 침지시킨 다음 60, 100, 150 및 300도의 온도에서 30분동안 노출하였다. 실험결과, 또한 FRP 보강근의 성능저하는 섬유의 종류뿐 아니라 수지의 종류와 제조과정에 따라 영향을 받는 것으로 관찰되었다. 침지 초기에는 ILSS 강도가 약간 증가한 후 시간경과에 따라 강도가 감소하는 것으로 나타났다. 알칼리 용액과 증류수 용액에 의해 손상을 받은 ILSS의 차이는 무시할 수 있는 수준인 것으로 관찰되었다.
Abstract
In spite of high resistant to corrosion and its strength, over the last two decades, concerns still remain about the durability of FRP materials under severe environmental and thermal exposures. In this paper, authors experimentally examine the combined degradation by thermal and chemical attacks in heterogeneous FRP rebar be made up with various fibers and resins. Five types of Carbon, Glass and Hybrid FRP rebars had manufactured by different process and surface patterns are adopted for the experiments such as weight change, interlaminar shear strength, SEM and FT-IR analysis. FRP specimens were immersed in alkaline or distilled solution up to 150 days and then thermal exposed on 60, 100, 150 and 300℃ for 30 minutes. From the test results, the degradation of FRP bars are influnced by the resin type and manufacturing process as well as the fiber, and ILSS of exposed FRP bar in solutions is slightly increased in initial stage and then decresed with the passing of immersed time. But, in this test, it is observed that the discrepancy of ILSS between degraded by alkaline solution and distilled water is negligible value.
참고문헌 (17)
- 문도영, "알카리저항 초단유리섬유를 리브에 사용한 유리섬유 보강근의 내구성능", 한국구조물진단유지관리공학회 논문집, 15(1), pp.281~287 (2011), 한국구조물진단유지관리공학회
- 원종필, "콘크리트 보강용 FRP 보강근의 수분 민감성 및 열화 특성", 대한토목학회 논문집A, 24(2004), pp.381~390 (2004), 대한토목학회
- "ACI Committee 440, “Guide for the Design and Construction of Concrete Reinforced with FRP Bars”", American Concrete Institute, ~ (2003)
- "ASTM D4475, “Standard test method for apparent horizontal shear strength of pultruded reinforced plastic rods by the short-beam method”", ASTM International, ~ (2002)
- Bisby, L. A., "Evaluating the fire endurance slabs reinforced with FRP bars: Considerations for a holistic approach", Composites Part B, 38, pp.547~558 (2007)
- Cardona F., "Investigation by TGA-FTIR of the Effect of Styrene Content and Thickness on the UV-Curing of Vinylester Resins", Journal of Thermoplastic Composite Materials, 20(6), pp.601~615 (2007)
- 김형열, "Accelerated aging tests for evaluations of durability performance of FRP reinforcing bars for concrete structures", Composite Structures, 78(1), pp.101~111, Elsevier BV
- Clarke, J. L., "Designing Durable FRP Reinforced Concrete Structures", Proceedings of the 1st International Conference on Durability of Fiber Reinforced Polymer (FRP) Composite for Construction, pp.13~24 (1998)
- Hong Shinn-Gwo, "DSC and FTIR analysis of the curing behaviors of epoxy", DICY, Thermo-chimica Acta, pp.1998, 316[DOI]
- 김형열, "Short-term durability test for GFRP rods under various environmental conditions", COMPOSITE STRUCTURES, 83, pp.37~47, ELSEVIER SCI LTD
- Micelli F, "Durability of FRP rods for concrete structure", Construction and Building Materials, 18, pp.491~503 (2004)
- 문도영, "An exploratory study of GFRP rebar with ribs containing milled glass fibers", COMPOSITES PART B-ENGINEERING, 39(5), pp.882~890 (2008), ELSEVIER SCI LTD
- Sen, R., "Durability of E-Glass", Vinylester Reinforcement in Alkaline Solution, 2002, pp.99(3), 369~375
- Uomoto, T., "Proceedings of the 3rd International Conference on Advanced Composite Materials in Bridges and Structures, ACMBS-3", Proceedings of the 3rd International Conference on Advanced Composite Materials in Bridges and Structures, ACMBS-3, pp.3~17 (2000), Canadian Society for Civil Engineering
- Won, J., "Effect of Environment Expose on the Mechanical and Bonding Properties of Hybrid FRP Reinforcing Bars for Concrete Structures", Journal of Composite Materials, 40(12), pp.1063~1076 (2006)
- Won, J., "The effect of exposure to alkaline solution and water on the strength–%porosity relationship of GFRP rebar", Composites Part B: Engineering, 39(5), pp.764~772 (2008)
- Zhu J., "Processing a glass fiber reinforced vinyl ester composite with nanotube enhancement of interlaminar shear strength", Composites Science and Technology, 67(7-8), pp.1509~1517 (2007)