Steel Buildings in Europe

Part 7: Fire Engineering 7 - 36       2 for 1 for i i i m ck m k K (31) ) 0,6 (1 1 2 2 1 2 2 1 ) ( 12 1 2 with c b 3 c h f l h f I I j m i j j c h f EI k                  (32) where, for each side in turn ( i = 1, 2): h is the height of the columns f is the ridgepole l is the length of the span I b is the second moment of area of the beam I c is the second moment of area of the column E is the modulus of elasticity of steel for normal temperature   f h m i =2 I b I c Figure 5.12 Definition of parameters of cold parts on side i of the frame Lateral stiffness K for fire at the end of a frame If fire compartment is at the end of the frame, K 2 should be calculated as for fire in the middle compartment. K 1 , which is defined as the lateral stiffness of the steel frame of the heated fire compartment, should be calculated as follows:                           frames lattice for 2 for 0,3 for 1 0,2 frames portal for 2 for 0,13 2 for 0,13 for 1 0,065 2 2 1 n K n K n c k n k n k K (33) where k and c are calculated from equation (32) with m 1 = n − 1, where n is the number of heated bays, as shown in Figure 5.13.