Thickness of fireproofing coating for concrete beams and slabs strengthened with CFRP sheets

For improving the fire-resistance of concrete beams and slabs strengthened with CFRP sheets, it is proposed that the thick fireproofing coating showld be utilized. Some parameters such as the ratio K of characteristic value for resistance to characteristic value for frequent combination of load at normal temperature K, the increase amplitude of load-carrying β of strengthened structures at normal temperature and the thickness of fireproofing coating c₀ were determined for investigation. Thus, concrete beams and slabs strengthened with CFRP sheets subjected to fire were calculated based on FEM programs of ANSYS and Matlab. The recommendation on the thickness of fireproofing coating c₀ for concrete beams and slabs strengthened with CFRP sheets was developed considering the parameters of K, β and the fire-resistance limit t_u.