Free-standing walls, parapets, fences, and signboards are directly exposed to wind and therefore require careful assessment of wind load effects to ensure structural safety. According to the relevant code provisions, the wind pressure acting on such elements depends primarily on their solidity ratio (φ), which represents the proportion of solid surface relative to openings. Solid walls are taken as φ = 1.0, while elements with openings—such as an 80% solid wall—are assigned φ = 0.8. Structures with φ ≤ 0.8 are treated as porous plane lattices following specialized lattice-type wind rules.
To determine wind load action effects, the net wind pressure is evaluated across the designated zones (A, B, C, and D) along the length of the wall or parapet. These pressures are calculated using the net pressure coefficients (cₚ,net), which represent the combined effect of wind on both the front and back faces of the structure. This approach ensures that the calculated forces accurately reflect the overall loading that the element will experience under real wind conditions.
