The flexural and shear bearing capacity of concrete beams strengthened with CFRP is significantly improved. CFRP can effectively inhibit the development of cracks, and make the width and spacing of cracks smaller.

In the late 1980s, based on the idea of bonded steel reinforcement, fiber reinforced plastic (FRP) was used to reinforce concrete structures. In recent years, it has been gradually popularized and applied at home and abroad, and has been fully industrialized. CFRP reinforcement technology is applicable to reinforcement and repair of various structural types and structural parts. Carbon fiber reinforced plastic (CFRP) reinforcement technology is a new external reinforcement technology widely used in fiber reinforced plastics.

Carbon fiber sheet reinforcement technology

1.1 carbon fiber reinforcement technology principle

Carbon Fiber Reinforced Polymer (CFRP) structure reinforcement technology refers to the use of high-performance adhesive CFRP will be pasted on the surface of building structural components, so that both work together to improve the bearing capacity of components, thus achieving the purpose of strengthening the building.

1.2 carbon fiber reinforcement characteristics

•  flexible

•  high strength

•  high modulus

•  easy to install

•  long shelf life

•  light self weight

•  high toughness

•  anti high temperature

•  environmental-friendly

1.3 material

Carbon fiber reinforced concrete structures are mainly made of carbon fiber and paste materials. Bonding material is an important guarantee for the success of construction.

Failure modes of concrete beams

2.1 detection of beam failure

Carbonation test of concrete, or rebound tester to test the strength of concrete, according to the method specified in the code for conversion of concrete cube compressive strength. The failure mode of beams is shown in Figure 1.

2.2 Reinforcement method

The reinforcement of reinforced concrete beams can be divided into: CFRP:

1) reinforce the RC beam by drawing.

2) reinforce the RC beam by drawing U and CFRP on both sides (see Fig. 2).

3) RC beam wrapped reinforcement;

4) stick and reinforce only on both sides of beams.

Construction technology of carbon fiber reinforced polymer(CFRP)

>>The treatment of concrete surface

>>Primer construction

>>Leveling construction

>>Paste of carbon fiber cloth

>>Curing and conservation

End

The ultimate strength and deformation of CFRP confined concrete are much higher than that of unconfined concrete. The greater the reinforcement rate of CFRP, the greater the degree of improvement. The flexural and shear bearing capacity of concrete beams strengthened with CFRP is significantly improved. CFRP can effectively inhibit the development of cracks, and make the width and spacing of cracks smaller. Compared with the existing reinforcement methods, carbon fiber reinforcement method has a broad prospect of development.