Steel Buildings in Europe

Part 7: Fire Engineering 7 - 18 For cross-section with a convex shape, such as hollow steel sections, fully embedded in fire, the shadow effect does not play a role and it can be taken that k sh = 1. Otherwise, the correction factor for the shadow effects k sh is given by:        cases others for actions fire nominal under sections for I - / / ] [ / / ] 0,9[ m m b m m b sh A V A V A V A V k (7) where: m b / ] [ A V is the box value of the section factor [m -1 ]. Application of the EN 1993-1-2 calculation method with standard ISO fire exposures of 15 and 30 minutes leads to the temperature curves illustrated in Figure 5.4 and given in Table 5.1 as function of the section factor including shadow effect ( A m / V ) sh = k sh A m / V . Figure 5.4 Temperature of unprotected steel members after 15 and 30 minutes of standard ISO fire exposure 0 100 200 300 400 500 600 700 800 900 0 50 100 150 200 250 300 350 400 450 500 ( A m / V ) sh = k sh  ( A m / V ) (m -1 ) Temperature (°C) 15 minutes 30 minutes 10