Steel Buildings in Europe

Part 6: Fire Engineering 6 - 19 Table 3.1 Example of datasheet for board fire protection Maximum Section factor A m / V (m -1 ) for beams and columns Thickness of board protection (mm) R30 R60 R90 R120 20 260 260 125 70 25 198 110 30 260 168 35 232 40 256 45 260 Table 3.2 Example of datasheet for sprayed non-reactive coatings Required thickness (mm) of sprayed non-reactive coatings Section factor A m / V (m -1 ) R30 R60 R90 R120 40 10 10 11 15 80 10 12 16 21 120 10 14 19 24 160 10 15 21 26 200 10 16 22 28 240 10 16 23 29 280 10 17 23 30 Table 3.3 Example of datasheet for intumescent coatings for R60 Section factor A m / V (m -1 ) 3 side- I beam 4 side- I beam 4 side– I column 40 0,25 0,26 0,26 80 0,31 0,39 0,39 120 0,39 0,53 0,53 160 0,48 0,66 0,66 200 0,69 0,83 0,83 240 0,90 1,00 1,00 280 1,08 1,74 1,74 3.3 Fire resisting construction In recognition of the importance of structural fire resistance and the costs associated with passive fire protection materials, some alternative structural systems have been developed which utilize their inherent fire resistance and avoid the need of dedicated fire protection. These systems include composite floors, integrated beams and encased steelwork. 3.3.1 Composite floor Precast concrete slabs have an inherent fire resistance of up to 120 minutes if adequate provision and detailing of rebar is made. However, the slabs usually rest on the top flange of a down stand beam (see Figure 3.7(a)), which is exposed on three sides and requires fire protection.