Due to factors such as improper design, construction, external environment, and earthquake disasters, existing reinforced concrete structures often exhibit external damage and defects such as cracking and aging, leading to structural safety, applicability, and durability performance can not meet the requirements of the structure, the structure need strengthening.

At present, there are many commonly used reinforcement methods for reinforced concrete structures. Here are two commonly used reinforcement methods for reinforced concrete beams: adhesive bonded steel plate method and externally bonded carbon fiber reinforced polymer method. The differences in the selection, design calculation and construction technology of the two reinforcement methods are compared in the article.

1) compared with steel products, carbon fibers are not susceptible to corrosion by harmful media, nor need to be cured. They are stable in performance and less affected by external environmental factors.

2) two kinds of reinforcement methods include stress lag, strain lag and the integration of old and new parts.

3) through the analysis of the flexural bearing capacity of the reinforced rectangular cross section beam, it can be seen that both of them consider the influence of the additional material on the stress of the original concrete structure during the calculation, and all are equivalent to the bottom tensile steel in the calculation.

4) the bonding steel plate strengthening method requires higher strength and smoothness of concrete members. The surface of steel plate and concrete must be cleaned before construction, and the construction process is complex. The carbon fiber strengthening method is simple and the construction period is short. The adhesive used in combination requires high strength and good durability.

5) from an economic point of view, the carbon fiber strengthening method is more economical than the sticky steel plate method in materials and labor costs.