Steel Buildings in Europe

Part 4: Detailed Design 4 – 42 5.4 Vertical bracing In a braced steel multi-storey building, the planes of vertical bracing are usually provided by diagonal bracing between two lines of columns, as shown in Figure 5.13. Figure 5.13 Typical positioning of vertical bracing The vertical bracing must be designed to resist the forces due to the following:  Wind loads.  Equivalent horizontal forces, representing the effects of initial imperfections, Section 2.4. These loads are amplified if necessary (  cr < 10) to allow for second order effects as described in Section 2.4. Forces in the individual members of the bracing system must be determined for the appropriate combinations of actions (see Section 3.2). For bracing members, design forces at ULS due to the combination where wind load is the leading action are likely to be the most onerous. 1 4 3 5 2 H H H F H H H H H H b b b b b Ed (a) (b) (c) (d)      At each floor level, H i = 0,025  V Ed, i where V Ed, i is the total design load applied at that floor level (a) Cross bracing (b) Diagonal bracing (c) Horizontal k bracing (d) Vertical k bracing Figure 5.14 Typical arrangements of vertical bracing (as Figure 2.3)