Steel Buildings in Europe

Title APPENDIX D Worked Example: Design of portal frame using elastic analysis 16 of 44 4 - 97 The restraint must be at a side rail position, since bracing from the side rail to the inner flange is used to provide the torsional restraint. 3800 1475 6000 0 kNm 616 kNm 444 kNm * * = 117 kN V N = 162 kN Ed Ed = 117 kN V N Ed Ed = 168 kN 7.5.3. Upper segment (1475 mm) As previously, the flexural buckling and the lateral torsional buckling checks are carried out separately before proceeding to verify the interaction between the two. Flexural buckling resistance about the minor axis, N b,z,Rd b h  200 500  2,5 t f  16 mm buckling about z-z axis:  Curve b for hot rolled I sections   z  0,34 EN 1993-1-1 Table 6.2 Table 6.1  1 = y f E  = 355 210000  = 76,4 EN 1993-1-1 §6.3.1.3 z  = z 1 cr 1  i L = 76, 4 1 43,1 1475  = 0,448  z =     2 z z z 0,2 0,51       =     2 0,51 0,34 0,448 0,2 0,448    = 0,643 EN 1993-1-1 §6.3.1.2  z = 2 z 2 z z 1      = 2 2 0, 448 0, 643 0, 643 1   = 0,906  z = 0,906