We need to know that carbon fiber cloth has four specifications: 300g, 200g, 300g, and 200g. Some drawings and design instructions will directly give the specifications of carbon cloth. For example, if the design instructions clearly state that the carbon cloth uses 300g first-class products, then we can directly explain this specification level to the material manufacturer.
If the design instructions do not clearly state the grade specification of the carbon cloth, we can judge the specification level of the material based on several key performance parameters of the material. For example, when the tensile strength of the carbon cloth is ≥3400MPa, the elastic modulus is 230GPa, and the elongation is 1.6%, then we can determine that the carbon cloth is a first-class product. If the tensile strength is ≥3000MPa, the elastic modulus is 200GPa, and the elongation is 1.5%, it indicates that the carbon cloth is a second-class product; the gram weight of the carbon cloth can be determined according to the thickness of the carbon cloth. The carbon cloth with a thickness of 0.167mm is 300g/㎡, and the carbon cloth with a thickness of 0.111mm is 200g/㎡.
Secondly, check whether the test report is complete
As a reinforcement material related to structural safety, the impregnation glue that matches the carbon fiber cloth must pass the safety appraisal. If the drawing requires a design life of 30 years, be sure to check whether the impregnation glue safety appraisal report includes a moisture and heat resistance test; if the drawing requires a design life of 50 years, the long-term stress resistance test of the impregnation glue must also be checked; the impregnation glue must also check the non-toxic test report. One of the items in the non-toxic test report is to detect the content of toxic substances such as benzene and xylene. If the product has this report, it means that the impregnation glue will not volatilize or volatilize very few harmful gases.
Observe the product appearance and construction experience
When the carbon fiber cloth and impregnation glue enter the site, check whether the appearance of the carbon fiber cloth is obviously uneven. During the construction process, you can feel whether the colloid is easy to use. If the colloid is too thick, the construction workers have a poor construction experience, and the colloid is difficult to fully penetrate the carbon cloth to achieve the best reinforcement effect. If the colloid is too thin, it will cause the impregnation glue to flow and affect the bonding effect.
