Browse > Article
http://dx.doi.org/10.4334/JKCI.2010.22.1.131

Development Length of GFRP Bars  

Ha, Sang-Su (Dept. of Architectural Engineering, Kangnam University)
Choi, Dong-Uk (Dept. of Architectural Engineering, Hankyong National University)
Publication Information
Journal of the Korea Concrete Institute / v.22, no.1, 2010 , pp. 131-141 More about this Journal
Abstract
The objective of this study was to propose a development length equation for GFRP bars. A total of 104 modified pullout tests were completed while the test variables were embedment length (15, 30, $45d_b$), net cover thickness ($0.5{\sim}2.0d_b$), top-cast bar effect, different GFRP bar types (K2KR, K3KR and AsUS), and bar diameters (10, 13, 16 mm). Average bond stresses were determined based on modified pullout test results. Two variable linear regression analysis was performed of the average bond stresses. Utilizing 5% fractile concept, a conservative development length design equation was derived. The design equation derived in this study was compared to the ACI 440 committee equation. The cross-comparison revealed that the current equation resulted in shorter development lengths than those determined by the ACI 440 equation when the net cover thickness was large (greater than $1.0d_b$). On the other hand, when the net cover thickness was small (equal to or less than $1.0d_b$), the development lengths required by the current equation were larger than those by the ACI equation. The bond stresses were significantly influenced by the cover thicknesses. The current equation results in development lengths that are more economical when the cover thickness is large, and more conservative lengths when the cover thickness is small than the ACI 440 committee equation.
Keywords
GFRP bars; embedment length; cover thickness; splitting failure; average bond stress;
Citations & Related Records
Times Cited By KSCI : 4  (Citation Analysis)
연도 인용수 순위
1 Wambeke, B. W. and Shield, C. K., "Development Length of Glass Fiber-Reinforced Polymer Bars in Concrete," ACI Structural Journal, Vol. 103, No. 1, 2006, pp. 11-17.
2 ACI 440 Committee, "Guide for the Design and Construction of Concrete Reinforced with FRP Bars (ACI 440.1R-06)," American Concrete Institute, Detroit, Michigan, 2006.
3 ACI 440 Committee, "Guide for the Design and Construction of Concrete Reinforced with FRP Bars (ACI 440.1R-03)," American Concrete Institute, Detroit, Michigan, 2003.
4 Japan Society of Civil Engineers, "Recommendations for Design and Construction of Concrete Structures Using Continuous Fiber Reinforcing Materials," Concrete Engineering Series, No. 23, 1997.
5 Architectural Institute of Japan, "Design and Construction Guideline of Continuous Fiber Reinforced Concrete," 2001.
6 ISIS Canada, "Reinforcing Concrete Structures with Fibre Reinforced Polymers," Design Manual, No. 3, 2001, 156 pp.
7 한국건설기술연구원, "FRP 복합재료 보강재 개발 및 이를 활용한 콘크리트 구조물 건설기술 개발," 1차년도 최종 보고서, 2004.
8 ACI Committee 355, "Qualification of Post-Installed Mechanical Anchors in Concrete (ACI 355.2-04)," American Concrete Institute, Detroit, Michigan, 2004.
9 유영찬, 박지선, 유영준, 박영환, "GFRP 보강근의 인장 강도 분석을 위한 시험방법 비교 연구," 콘크리트학회 논문집, 18권, 3호, 2006, pp. 303-312.
10 ASTM D3916-02, "Standard Test Method for Tensile Properties of Pulltruded Glass -Fiber-Reinforced-Plastic Rods," American Society of Testing Materials, 2002.
11 최동욱, 하상수, 이창호 "인발실험에 의한 GFRP 보강근의 정착길이 제안," 콘크리트학회 논문집, 19권, 3호, 2007, pp. 323-331.   DOI
12 최동욱, 하상수, 천성철, "RC 부재 휨 실험에 의한 GFRP 보강근의 이음길이 제안," 콘크리트학회 논문집, 21권, 1호, 2009, pp. 65-74.   DOI
13 Eshani, M. R., Saadatmanesh, H., and Tao, S., "Design Recommendations for Bond of GFRP Rebars to Concrete," ASCE J. of Structural Engineering, Vol. 122, No. 3, 1996, pp. 247-254.   DOI
14 CAN/CSA S806-02, "Design and Construction of Building Components with Fibre-Reinforced Polymers," Canadian Standard Association, Rexdale, Ontario, Canada, 2002: Annex H., "Test Method for Bond Strength of FRP Rods by Pullout Testing."
15 한국건설기술연구원, "FRP 복합재료 보강재 개발 및 이를 활용한 콘크리트 구조물 건설기술 개발," 2차년도 최종 보고서, 2005.
16 박찬기, 원종필, 강주원, "콘크리트 보강용 FRP 보강근의 내구성 설계를 위한 환경영향계수의 제안," 콘크리트학회 논문집, 16권, 4호, 2004, pp. 529-539.   DOI