Carbon Fiber Reinforced

The spillway tunnel of the Nianzigou Reservoir in Yongji County, Jilin Province was built in the 1950s. The spillway tunnel is 32.2 m long and has a total of 3 holes. The cross-section size of each hole is 3.55 m×3.4 m (b×h). The side wall and bottom plate of the cave are reinforced concrete U-shaped groove structure, and the top is reinforced concrete T-beam cover plate. In 2003, the reservoir was reinforced by risk elimination. As the crest of the earth dam was increased by 0.38 m, after review, the reinforcement of the T-shaped beam on the top of the spillway tunnel did not meet the strength requirements. Through calculation, the design uses 300 g/m2 carbon fiber cloth to stick to the bottom of the full beam. Carbon fiber paste uses carbon fiber supporting resin (epoxy resin), the specific construction method is as follows:

Concrete surface treatment, that is, polish the surface of the concrete, remove the surface mortar and loose parts, and use a blower to blow off the floating ash. Prepare and apply the primer, mix the primer in the ratio of main agent: curing agent, 2:1 (mass ratio), stir for 3 to 5 minutes, and use it until it is fully uniform. Prepare leveling glue and repair the unevenness. Prepare and apply the dipping glue, apply the mixed dipping glue to the reinforcement position, and paste the carbon fiber cloth.

Carbon fiber reinforcement has an excellent effect on strengthening structures. It can retain the structural characteristics of the original building to the utmost extent, does not increase the weight of the structure, does not change the appearance of the original building structure, the construction speed is fast and the project cost is low.

The reinforcement construction of the spillway tunnel of Nianzigou Reservoir only took 4 days, and the potential safety hazard was solved with an investment of more than 40,000 yuan. At present, the spillway tunnel is operating well.