Fundamental basic wind velocity map to consider in France Altitude effect according to NF EN 1991-1-4/NA (03 2008)
Clause 4.2 (2)P NOTE 1: The statistical study of meteorological data in France showed no influence of altitude on the wind reference speed vb.
Fundamental basic wind velocity map to consider in Belgium Altitude effect according to NBN EN 1991-1-4 ANB (12 2010)
4.2 (2)P NOTE 1: The influence of altitude is included in the values of vb,0 given in Figure 4.3 ANB and Table 4.2 ANB.
Fundamental basic wind velocity map and effect of altitude to consider in United Kingdom Altitude effect according to NA to BS EN 1991-1-4 (01 2011)
(from NA.2.4 Equation NA.1)
- vb,map is the value of the fundamental basic wind velocity before the altitude correction is applied.
- calt is the altitude factor: