Steel Buildings in Europe

Part 5: Detailed Design of Trusses 5 - 32 The effective width of the web is evaluated according to EN 1993-1-5 (Table 4.1): 4 1      k 0,782 0,673 28,4 0,81 4 7,5 271 28,4 σ p       k t b   124,5 mm 0,5 249 mm 271 0,919 0,055(3 ) 0,919 0,782 0,673 28,4 0,81 4 7,5 271 28,4 4 1 eff e2 e1 eff 2 p p σ p σ                      b b b b k t b k        b eff = 0,919 × 271 = 249 mm b e1 = b e2 = 0,5 b eff = 124,5 mm The effective area of the section is: A eff = 6260 – (271 – 249) × 7,5 = 6095 mm 2 The effective elastic modulus about the weak axis ( W eff,z ) is calculated for pure bending. In simple bending in the plane of the truss, about the weak axis, the flanges are inevitably Class 1, whilst the web is not stressed. Then the section is fully effective: W eff,z = W el,z = 98,5 cm 3 Resistance of cross-section In compression (EN 1993-1-1 §6.2.4): 1,0 6095 0,355 M0 eff y c,Rd     A f N = 2164 kN 0,683 1 2164 1477 c,Rd Ed    N N OK In bending in the plane of the truss (EN 1993-1-1 §6.2.5): 34,97 kNm 1,0 98,5 0,355 M0 eff,z y z,Rd      f W M 0,082 1 34,97 2,86 z,Rd Ed    M M OK In shear (EN 1993-1-1 §6.2.6): A v,y = 2×160×11,5 = 3680 mm 2