European Recommendations on the Stabilization of Steel ... - Xs4all

<strong>European</strong> <strong>Recommendations</strong> on the Stabilization of Steel Structures by Sandwich PanelsExample No. 2: Torsional restraint of a cold-formed C-sectionSandwich wall panels are used to stabilize a cold-formed C-section. The second momentof inertia about the weak axis is I z = 101.9 cm 4 . The section is loaded by a transverse load(wind pressure)q d = 2.7 kN/m (ultimate limit state)q d = 1.8 kN/m (serviceability limit state)which results in a bending moment M E,d . The section is installed as a single span system witha span of 4.5 m. The section shall stabilized against lateral torsional buckling.For the sandwich panels, the following parameters apply:- Core material PUR, E Cc = 4 N/mm², E Ct = 3 N/mm², f Cc = 0.12 N/mm².- Steel faces with nominal thicknesses t F1 = 0.50 mm, t F2 = 0.40 mmThe C-section has a width of the flange of b = 60 mm. Fixing is done with at least twofasteners per panel with a width of one meter (n f ≥ 2 m -1 ).Fig. A.5: C-section, sandwich panel and fasteningThe requirements according to Table 2.4 are met.Modulus of elasticity of the core:⎛ N N ⎞E C= 0.5⋅⎜3=⎝ mm mm ⎠+ 4 3. 52 2⎟No reduction for duration of loading (creep) is required. The action with the shortest time ofload duration becomes crucial. For the action of the wind load, φ ϑ,t = 0.0. During the time ofloading, a temperature of 0°C is assumed in this example. From Table 2.3, we obtain c 3 =5.11∙10 -4 m 2 .andCNmm−42 N Nmm kNm= c3⋅ EC,t= 5.11⋅10m ⋅3.5= 1789 1. 7892mm mm mϑ 1=258