Mechanical performance of concrete strengthened by modified epoxy resin bonded CFRP

Abstract

Mechanical performance of concrete strengthened by modified epoxy resin bonded CFRP (carbon fiber reinforced polymer) is present in this paper, with particular focus on the interface bond strength and flexural strength. A type of modified epoxy resin adhesive which bonds CFRP sheets to strengthen plain concrete was developed. The interface bond strength between CFRP and concrete and the flexural strength of CFRP reinforced concrete were comprehensively tested. The influence of the CFRP size, number of CFRP bonding layers, and concrete strength was further analyzed. The results showed that CFRP significantly improved the maximum bearing capacity, displacement and failure energy of plain concrete. The bearing capacity of plain concrete improved almost linearly with an increasing number of CFRP layers. CFRP-reinforced low-density concrete has a better strengthening effect than high-density concrete. The final strength and failure energy of the CFRP-reinforced concrete increased significantly, compared to that of plain concrete. A model for calculating the maximum flexural strength of reinforced concrete structures is proposed.

Keywords:

• Modified epoxy resin
• CFRP
• strengthening effect
• interface bonding strength
• flexural strength

Disclosure statement

No potential conflict of interest was reported by the authors.

Data availability statement

All data generated or analyzed during this study are included in this published article.

Additional information

Funding

This project was supported by the National Natural Science Foundation of China [grant number 51908182] and the Natural Science Foundation of Hebei Province [grant number E2020202043].