Considering Correlation for Wind Loads

For buildings with an aspect ratio of h / d = 5, the resulting force is multiplied by 1. For buildings with h / d = 1, the resulting force may be multiplied by 0.85. Intermediate values of h / d are linearly interpolated.

However, it must be ensured that the consideration of this approach can be limited by the National Annex of DIN 1991-1-4 [1]. Thus, this approach does not apply (for example, according to DIN EN 1991-1-4/NA [2]) in Germany.

Example

National Annex: CEN

Building height h = 7 m
Building width d = 6 m
Ratio h / d = 1.166667

Generate Wind Loads

External pressure coefficients according to Table 7.1:
Zone D: c_pe,10 = 0.800
Zone E: c_pe,10 = -0.508

Basic wind speed v_b,0 = 20 m/s

Resulting wind load without consideration of the correlation:
Zone D: w_e = 0.56 kN/m²
Zone E: w_e = -0.35 kN/m²

Resulting wind load with consideration of the correlation:
Zone D: w_e = 0.56 kN/m² ∙ 0.85 = 0.48 kN/m²
Zone E: w_e = -0.35 kN/m² ∙ 0.85 = -0.30 kN/m²

Info About Wind Load Generation

Depending on whether the correlation in the respective National Annex is allowed or not, this can be activated in the input table of the wind load generator in RFEM / RSTAB (see Fig. 01).

Literature