Mechanical behavior of CFRP on steel surface molded and bonded by vacuum-assisted resin transfer molding technology

• Published in: SN applied sciences Vol. 1; no. 6; p. 601
• Main Authors: Mieda, Genki, Nakamura, Hitoshi, Matsui, Takahiro, Ochi, Yutaka, Matsumoto, Yukihiro
• Format: Journal Article
• Language: English
• Published: Cham Springer International Publishing 01.06.2019; Springer Nature B.V
• Subjects: Adhesion; Adhesive strength; Adhesives; Aging (metallurgy); Applied and Technical Physics; Bend strength; Bend tests; Bond strength; Bonding strength; Carbon; Carbon fiber reinforced plastics; Carbon fibers; Chemistry/Food Science; Civil engineering; Coatings; Construction; Earth Sciences; Engineering; Engineering: Advances in Technology and Systems; Environment; Finite element method; High strength; Materials Science; Mechanical properties; Resin transfer molding; Review Paper; Shear forces; Shear tests; Steel; Strain gauges; Stress concentration; Structural members; Surface treatment; Vacuum; Weight reduction; Workability; Japan; Bond strength; VaRTM; CFRP; Composite structure
• ISSN: 2523-3963; 2523-3971
• DOI: 10.1007/s42452-019-0603-4

This research is aimed to develop repair and reinforcement methods with excellent workability and usefulness for steel structural members that have been damaged through aging. Fiber-reinforced plastic, which has been used in various fields in recent years, is also used for building and civil engineering. Especially, it is assumed that carbon fiber-reinforced plastic (CFRP) has light weight and high-strength mechanical properties. Conventional methods of repair and reinforcement using CFRP are mainly hand-lay-up molding methods using carbon fiber sheet and adhesion methods using CFRP plate. However, both methods have some issues. Therefore, we apply the vacuum-assisted resin transfer molding to repair and reinforce steel structural members; the proposal of a construction procedure and a basic investigation of bond strength were carried out. In the basic investigation, a double-strap tensile shear test and a three-point bending test of steel/CFRP composite specimens were carried out. In the double-strap tensile shear test, in order to improve the adhesiveness of CFRP, the adhesive strength against shear force was compared between the specimen pre-coated with resin and a specimen not coated with resin after surface treatment. The results showed that the pre-coated specimen had high strength and stability. In the three-point bending test, bond strength and fracture mode against bending force were analyzed using adhesion length and number of laminated carbon fiber sheets as parameters. From the finite element method, the stress when peeling occurs due to the bending deformation was estimated and compared with the experimental result.