On the map of the national annex, the Belgian area is divided into four wind zones.
| Fundamental value of the basic wind velocity vb,0 | 23 m/s | 24 m/s | 25 m/s | 26 m/s |
|---|
Wind zoning of Belgium (2010-2024)
0 -
Sea or coastal area exposed to the open sea.
I -
Lakes or area with negligible vegetation and without obstacles.
II -
Area with low vegetation such as grass and isolated obstacles (trees, buildings) with separations of at least 20 obstacle heights.
III -
Area with regular cover of vegetation or buildings or with isolated obstacles with separations of maximum 20 obstacle heights (such as villages, suburban terrain, permanent forest).
IV -
Area in which at least 15%% of the surface is covered with buildings and their average height exceeds 15m.
See the features of Eurocodes Zoning for snow analysis in Belgium
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| Coordinates | 4.9013°, 50.241° | 4.9044°, 50.2436° | ||
|---|---|---|---|---|
| Elevations | 96m | 189m | ||
| Obstacle effective height H | 93m | |||
| Slope actual length Lu / Ld | 361.4m | |||
| Slope angle Φ | 25.7% | |||
| Horizontal distance site/top x | 121.2m | |||
| Elevation at the place of construction | 197m | |||
| Sectors | 1 | 2 | 3 | 4 |
|---|---|---|---|---|
| Categories | II | II | III | II |
NBN EN 1991-1-3 ANB (october 2007)
NBN EN 1991-1-4 ANB (december 2010)
| Sectors | 1 | 2 | 3 | 4 |
|---|---|---|---|---|
| Sector definition | from 350 ° to 80 ° | from 80 ° to 170 ° | from 170 ° to 260 ° | from 260 ° to 350 ° |
| Fundamental value of the basic wind velocity vb,0 | 24.0m/s | |||
| Shape parameter K | 0.2 | |||
| Exponent n | 0.5 | |||
| Annual probability of exceedence p | 0.01 | |||
| Probability factor cprob | 1.038 | |||
| Directional factor cdir | 1.0 | 0.983 | 1.0 | 1.0 |
| Basic wind velocity vb | 24.9m/s | 24.5m/s | 24.9m/s | 24.9m/s |
| Reference roughness length z0,II | 0.05m | |||
| Roughness length z0 | 0.05m | 0.05m | 0.3m | 0.05m |
| Terrain factor kr | 0.19 | 0.19 | 0.215 | 0.19 |
| Height above ground z | 7.0m | |||
| Minimum height zmin | 2.0m | 2.0m | 5.0m | 2.0m |
| Roughness factor cr(z) | 0.939 | 0.939 | 0.678 | 0.939 |
| Obstacle type | cliffs | |||
| Exposure type | - | - | downwind | - |
| Factor depending on the type and dimensions of the obstacle s max | 0.0 | 0.0 | 0.598 | 0.0 |
| Orography factor * co(z) | 1.0 | 1.0 | 1.308 | 1.0 |
| Mean wind velocity vm(z) | 23.4m/s | 23.0m/s | 22.1m/s | 23.4m/s |
| Turbulence factor kl | 0.995 | 0.995 | 1.247 | 0.995 |
| Standard deviation of the turbulence σv | 4.713m/s | 4.634m/s | 6.696m/s | 4.713m/s |
| Turbulence intensity Iv(z) | 0.201 | 0.201 | 0.303 | 0.201 |
| Air density ρ | 1.225kg/m3 | |||
| Exposure factor ce(z) | 2.124 | 2.124 | 2.456 | 1.124 |
| Peak velocity pressure qp(z) | 824.7N/m2 | 797.5N/m2 | 953.3N/m2 | 824.7N/m2 |
| Peak wind velocity for Serviceability Limit States vp(z),SLS | 130.8km/h | 128.6km/h | 140.6km/h | 130.8km/h |
| Peak wind velocity for Ultimate Limit States vp(z),ULS | 160.2km/h | 157.5km/h | 172.2km/h | 160.2km/h |
NBN EN 1998-1 ANB (october 2011)
