Steel Buildings in Europe

Title APPENDIX D Worked Example: Design of portal frame using elastic analysis 28 of 44 4 - 109 LT,0   0,4 and   0,75 b h  2,37  Curve c for hot rolled I sections   LT  0,49 EN 1993-1-1 Table 6.3 Table 6.5     2 LT 0,51 0,49 0,470 0,4 0,75 0,470       = 0,60  LT = 2 LT 2 LT LT 1        LT = 2 2 0, 60 0, 60 0, 75 0, 470 1    = 0,961 EN 1993-1-1 §6.3.2.3 2 LT 1  = 2 0, 470 1 = 4,53   LT = 0,961 M b,Rd = M1 pl,y y LT   W f = 6 3 10 1, 0 355 10 1702 0,961      = 581 kNm M Ed = 356 kNm < 581 kNm OK Interaction of axial force and bending moment – out-of-plane buckling Out-of-plane buckling due to the interaction of axial force and bending moment is verified by satisfying the following expression: 1, 0 b,Rd y,Ed zy b,z,Rd Ed   M M k N N EN 1993-1-1 §6.3.3(4) For z   0,4, the interaction factor, k zy is calculated as: k zy =                             b,z,Rd Ed mLT b,z,Rd Ed mLT 0, 25 0,1 ; 1 0, 25 0,1 max 1 N N C N N C z  The bending moment is approximately linear and constant. Therefore C mLT is taken as 1.0 EN 1993-1-1 Annex B Table B.3 k zy =                            3034 127 1 0, 25 ; 1 0,1 3034 127 1 0, 25 max 1 0,1 0,540 = max (0,997; 0,994) = 0,997 EN 1993-1-1 Annex B Table B.2 b,Rd y,Ed zy b,z,Rd Ed M M k N N  = 581 0 ,997 356 3034 127  = 0,653 < 1,0 OK