Beam Strengthening

Overview of reinforcement works

In a three-storey industrial workshop, the bottom layer adopts a beam-column structure, the main beam span is 8.2m, the beam spacing is 6 m, the beam cross-sectional size is 250 mm × 580 mm; the upper layer is a brick-concrete structure. The main beam adopts prefabricated reinforced concrete beam, and the top end is welded with the embedded steel plate on the column side through embedded parts. The concrete strength grade is C25. When the age reaches 60 days, the core is taken. The representative value of the strength is 20.3 M Pa, which does not meet the design requirements. After analyzing the reasons, it was decided to choose carbon fiber reinforced polymer(CFRP) for reinforcement.

Carbon fiber reinforced polymer(CFRP) retrofitting

Carbon fiber cloth is used to reinforce the beam. Two layers of carbon fiber cloth are pasted on the bottom of the beam, a U-shaped hoop carbon fiber cloth with a width of 150mm and a pitch of 150mm is pasted on the side of the beam, and a carbon fiber cloth with a width of 150mm is pasted on both sides of the upper part of the beam.

Conclusion

The project proves that CFRP reinforcement technology is ideal for the reinforcement of concrete structural members. On the premise of basically not increasing the size and weight of the beam section, the technology has reached reasonable requirements in terms of construction period, material durability and construction quality. It has the advantages of convenient construction, high efficiency, low noise and tidy site. Moreover, carbon fiber has good acid resistance, alkali resistance, and atmospheric corrosion resistance, and will be more widely used in future engineering practice. Its comprehensive economic and social benefits are good, and it has a large value of promotion and use.