Carbon fiber CFRP on-site reinforcement is to use an adhesive to stick carbon fiber fabric on the component. Different materials, different bonding parts and different methods produce different reinforcement effects. Because the advantages of carbon fiber reinforcement materials are more prominent, the application range of this reinforcement method is wider.

CFRP for strengthening masonry structure

Under normal circumstances, construction personnel must use two or more layers of carbon fiber cloth to meet the needs of building brick masonry structure reinforcement. However, other reinforcement methods need to be selected in the actual engineering renovation and reinforcement of more than 3 floors. Because the utilization rate of carbon fiber cloth is very low, even if three or more layers of carbon fiber cloth material are selected, the reinforcement effect that can be achieved is relatively limited, and the material cost to be consumed is relatively high, which is not economical.

If the strength of the masonry structure of the building is small in terms of aspect ratio, the construction personnel can achieve the goal of improving the structural bearing capacity through on-site reinforcement of carbon fiber cloth. If the height and width of the building's masonry are relatively large, the carbon fiber cloth reinforcement method will have great limitations on the bearing capacity of the masonry structure.

When the stress ratio of other structures of the building is less than 0.4, the on-site reinforcement effect of carbon fiber cloth is limited. The construction personnel first need to analyze the structural reinforcement design plan, determine the relationship between the compressive strength of the masonry structure and the superstructure load, and analyze the feasibility of the carbon fiber reinforcement technology. If the stress ratio of the masonry structure exceeds 0.6, other reinforcement methods are selected.

Because when the stress of the masonry structure is high, although the carbon fiber cloth has a better reinforcement effect, the utilization rate of the carbon fiber cloth is low, and the required reinforcement cost is higher. If the stress ratio of the masonry structure is within 0.4-0.6, carbon fiber cloth can be selected for reinforcement.

CFRP for bridge reinforcement

In the reconstruction and reinforcement of highway and bridge projects, construction personnel need to combine with the specific requirements of engineering design to formulate a reasonable structural design plan.

Take a highway bridge project in City A as a research case. The project has 8 holes with a span of 20m. The upper bridge is a reinforced concrete structure, and the lower part is a bridge abutment. The bridge span is 163.5m, and there are 14,000 vehicles traveling daily.

The single-layer carbon fiber specification is 300g/m, the tensile strength must exceed 3000MPa, the elastic modulus must be greater than or equal to 2.lxlO'MPa, and the flat layer material's positive tensile bonding strength exceeds 2.5MPa.

During the on-site reinforcement of the bridge structure, the construction personnel should first control the temperature of the construction environment to keep the temperature of the construction environment above 5°C. If the construction environment temperature is less than 5°C, necessary measures can be taken to adjust the construction environment temperature.

Different repair methods are selected for different parts, such as pitted surfaces, piers and honeycombs, should be repaired with cement mortar, and the hollow slab of the whole bridge should be repaired with oblique section shear. When sticking carbon fiber cloth, you should choose to stick it from the middle to both sides to prevent adverse effects on the sticking effect.

CFRP for reinforcement of reinforced concrete structures

Because air bubbles will cause the resin to stain and affect the application effect of carbon fiber cloth. During the on-site reinforcement of reinforced concrete structures with carbon fiber cloth, the construction personnel must always ensure that the fiber cloth is in a tensioned state, and each bundle of carbon fiber cloth cannot be discounted.

After the carbon fiber cloth reinforcement treatment is completed, the quality of each layer of carbon fiber cloth should be inspected, and the lower layer can be pasted only after the inspection side is qualified.

In terms of quality inspection of carbon fiber cloth paste, sampling inspection can be carried out by hammering method. If the hollow drum area accounts for no more than 5% of the total adhesive area, it indicates that the adhesive quality meets the engineering quality standards.

CFRP for cooling tower reinforcement

In the cooling tower reinforcement treatment, the herringbone column reinforcement method can be adopted, and the carbon fiber cloth reinforcement range must be controlled within 1.3m from the upper and lower ends of the herringbone column. For the serious defects in the reinforcement of the herringbone column, it can be repaired by grouting and sticking carbon fiber cloth reinforcement, and the surface of the herringbone column can be anti-carbonized construction.

In the concrete cooling tower carbon fiber cloth reinforcement treatment, the construction personnel must chisel off the loose concrete, clean the roadbed surface, and take necessary rust prevention and rust removal measures for the exposed steel structure.

For the exposed steel bars of the cooling tower ring beam and the wall of the tower tube, the carbon fiber part and local repair measures must be taken. For the corrosion of the inner wall of the cooling tower barrel, a special anti-corrosion coating must be selected for anti-corrosion treatment.

In the aspect of unidirectional carbon fiber cloth reinforcement for the wall of the cooling tower tube, the crack repair treatment can be carried out by polymer cement and mortar, and the carbon fiber cloth reinforcement treatment on the outer part of the tube wall can be carried out by using asymmetrical reinforcement to give full play to the tensile properties of the carbon fiber cloth. .