ABSTRACT

The unsafety of the current design guidelines in Annex H of EN 1994-1-2 for the calculation of the fire resistance of slender Concrete-Filled Steel Tubular (CFST) columns was highlighted in previous investigations, which led to an addenda approved by CEN/TC250/SC4 limiting its application to columns of a maximum 0.5 relative slenderness. As one of the outcomes from the recently concluded RFCS European Project FRISCC, a simplified design method for the fire resistance of CFST columns was developed, covering all the practical range of application of CFST columns and including different cross-section shapes. The method is applicable to both axially and eccentrically loaded columns, accounting for minor and major axis eccentricities and considering the possibility of loads applied out of the section. Bending moment—axial force interaction curves specially built up for the fire situation are proposed for eccentric loads, being in line with the method in EN1994-1-1 for cold design.