Steel Buildings in Europe

Part 5: Detailed Design of Trusses 5 - 33 754 kN 1,0 3 3680 0,355 3 M0 y v,y pl,Rd      f A V 0,002 1 754 1,82 pl,Rd Ed    V V OK Since V Ed / V pl,Rd is less than 0,5, there is no influence of the shear force on the resistance of the cross-section under bending moment and axial force. M-N interaction (EN 1993-1-1 §6.2.93): The M-N interaction is taken into account using the following criterion: 0,683 + 0,082 = 0,765 < 1 OK Buckling resistance of member Buckling resistance in the plane of the truss, i.e. about the weak axis of the cross-section (EN 1993-1-1 § 6.3.1) The buckling length of the upper chord member is equal to 90% of the system length (EN 1993-1-1 §B.B.1.1): L cr,z = 0,9 × 2151 = 1936 mm The elastic critical force is: 4357 kN 193,6 788 21000 π π 2 2 2 z z 2 cr,z      l EI N The slenderness is given by: 0,705 4357 6095 0,355 , eff     cr z y z N A f  The buckling curve to use is curve b (EN 1993-1-1 Table 6.2), and the imperfection factor is:  = 0,34 ) 0,8344 0,5 (1 ( 0,2) 2 z z          z Φ 0,781 0,705 0,8344 0,8344 1 1 2 2 2 z 2 z z          Φ Φ z The design buckling resistance is then: 1690 kN 1,0 6095 0,355 0,781 M1 eff y z b,z,Rd        A f N N Ed / N b,z,Rd = 1477/1690 = 0,874 OK