Zones for snow, wind and seism

• First, the high velocities of wind are observed more frequently in certain direction sectors; the directional factor accounts for this by authorizing a reduction when the wind comes from a direction where the probability of occurrence of strong winds is less.
• On the other hand, the orography and the roughness of the terrain generally vary with the direction of the wind.
• Finally, the pressure or force coefficients depend on the direction of the wind relative to the construction.

• the wind zone according to the map taken from the national annex to the Eurocode 1 part 1-4.
• the directional factor c_dir.
• the annual probability of exceedence by calculating the basic wind velocity v_b with a return period equivalent to the design working life of your building.
• the roughness factor c_r(z), to take into account the effect of the environment (vegetation / urbanization).
• the orography factor c_o(z), to take in account the effect of terrain relief.

• q_p is the pressure in newtons per square meter (N/m²).
• I_v(z) is the turbulence intensity, at height z, defined as the standard deviation of the turbulence divided by the mean wind velocity.
• ρ is the air density in kilogram per cubic meter (kg/m³).
• c_e is the exposure factor: , with the basic velocity pressure

In cases of very low seismicity, the provisions of Eurocode 8 need not be observed.
It is recommended to consider as very low seismicity cases either those in which the design ground acceleration on type A ground, a_g = γ_I . a_gr, is not greater than 0.39m/s², or those where the product a_gS is not greater than 0.49m/s².
The seismic zones, the a_gr values and the chosen method may be found in national Annexes or in the law specific to each country. §3.2.1(5)

(Description of type A ground: Rock or other rock-like geological formation, including at most 5m of weaker Inaterial at the surface)

B1 - Localization

Coordinates in World Geodetic System 1984 (WGS84) :6.9511° , 43.4979°
Coordinates in French Geodetic System 1993 (Lambert 93) :1019565m , 6274536m

Address :06590 Théoule-sur-Mer, Provence-Alpes-Côte d'Azur

B2 - Elevations

Coordinates	6.9536° 43.4972°	6.9455° 43.4994°	6.9455° 43.4994°	6.9368° 43.5019°
Elevations	9m	244m	244m	54m
Obstacle effective height H	235m		190m
Slope actual length Lu / Ld	698.4m		754.4m
Slope angle Φ	33.7%		25.2%
Horizontal distance site/top x	483.1m
Elevation at the place of construction	58m

B3 - Building

B4 - Terrain categories

Sectors	1	2	3	4
Categories	IIIb	0	0	IIIb

Radius R of the angular sector : 300m

C1 - Snow NF EN 1991-1-3/NA (may 2007) + A1 (july 2011)

C2 - Wind NF EN 1991-1-4/NA (march 2008) + A1 (july 2011) + A2 (september 2012) + A3 (april 2019)

C3 - Seism Code of the Environment - Article D563-8-1 (09/01/2015) + JORF n°0248 of 24/10/2010 text N°5