Step 5
Calculate the racking force provided by the diagonal (structural) bracing.
It is usual to provide one diagonal brace per wall and two (opposing) wherever space permits in long walls. Table 8.18 in AS 1684.2 illustrates the allowable limits for angle bracing.
This is the process to follow:
- Determine the length of wall that the brace is acting on.
- Multiply this by the bracing capacity. For basic timber and metal angle brace, the bracing capacity is 0.8 kN per metre.
Formula
Racking force for bracing (kN/m) = length of wall (m) x bracing capacity (kN)
The braces should be set up in opposing pairs. Do not allow single braces to exceed 2.7 m in wall length.
In this example, the braces are at 45°, so the maximum length of wall braced by a single brace will be 2.4 m.