ISSN 2288-2103 (Print)
ISSN 2288-2111 (Online)
 
 
 
Journal Information
View Full Text
 
 
 
 
Full Text

The Journal of the Korean Society for Composite Materials. 2019 32(1): 37-44
ⓒ The Journal of the Korean Society for Composite Materials
    
 
Effect of Micro-bolt Reinforcement for Composite Scarf Joint
Gwang-Eun Le, Jung-Won Sung, Jin-Hwe Kweon
School of Mechanical and Aerospace Engineering, Gyeongsang National University
 
 
 
복합재 스카프 조인트에서의 마이크로 볼트 보강에 대한 타당성 연구
이광은, 성정원, 권진회
School of Mechanical and Aerospace Engineering, Gyeongsang National University
 

The reinforcement effect of micro-bolt for a bonded scarf joint was investigated. Three scarf ratios of 1/10, 1/20, and 1/30 were considered to examine the effect of scarf patch configuration on joint strength. To maintain the same density of micro-bolt, 16, 32, and 48 bolts were installed in the scarf joint specimens with scarf ratios of 1/10, 1/20, and 1/30, respectively. Tests were also carried out on the joints that are bonded with only adhesive and that are fastened with only micro-bolts to obtain reference values. The average failure loads of the adhesive joints with scarf ratios of 1/10, 1/20, and 1/30 were 29.7, 39.6, and 44.8 kN, respectively. In case of micro-bolt reinforcement, the failure loads at the same scarf ratios were 28.4, 37.2, and 40.1 kN, respectively, which corresponds to 96, 94, and 90% of the pure adhesive joint failure loads. In the case of using only micro-bolts, the failure loads were only 13-25% of the average failure loads of pure adhesive joints. Fatigue test was also conducted for the joints with scarf ratio of 1/10. The results show that the fatigue strength of hybrid joints using both adhesive and microbolts together slightly increased compared to the fatigue strength of adhesive joint, but the rate of increase was small to 2-3%. Through this study, it was confirmed that the reinforcement effect of micro-bolt is negligible in the scarf joints where shear stress is dominating the failure, unlike in the structure where peel stress is dominant.
 
Key words : Composite repair, Scarf repair, Micro-bolt
중심단어 : 복합재 수리, 스카프 수리법, 마이크로 볼트
 
Address for reprints : Jin-Hwe Kweon, School of Mechanical and Aerospace Engineering, Gyeongsang National University
Tel : ,    Fax : ,    E-mail : jhkweon@gnu.ac.kr
 
 
 
 
  
 
 
 

The Korean Society for Composite Materials / 137-070) 1337, Seocho 2-dong, Seocho-gu, Seoul, Korea
Tel: +82-2-598-1550 / Fax: +82-2-598-1557 / Email: composites@kscm.re.kr Copyright 2008 by the Korean Society for Composite Materials