h altitude of the building site
hr reference altitude (= 300 m)k coefficient: k = 1.25 for coastal regions, k = 1.5 for inland mountain
regions
The snow load on the ground Sg is defined as the product of the snow depth d and the snow
weight density 6
d :
S gdd 6
(7.21)where:
0
() ln1 exp 1
d
d
d(6 6
6
6(
FGH !
I 8 "
H JK^ $%
H
9 L
H
(7.22)
and 6
5.00kN m/^3 , 6
01.70 / kN m^3 and (0.85m.
The coefficient of variation of the snow depth can roughly be estimated by: d
(climate) hh/r
mAd k (7.23)(climate) hh/2^ r
dAk (7.24)
-/2hh (^) r
Vkd (7.25)
where:
A(climate): is the mean snow density for a reference height
k: a value between one and two
h: is the height at which the building is situated
hr 300 m: is the reference height.
If the height is chosen to be h 600 meters and k1.5 then the coefficient of variation of
the snow depth is Vd0.67. The coefficient of variation of the snow weight density V 6 lies
between 15% and 25%.
In accordance with JCSS (2001) the Gamma distribution is selected for the probabilistic
modelling of the snow load on ground Sg, however, also the Gumbel distribution can be
applied.
The conversion factor r takes into account the transformation of the ground snow load to the
roof and is defined as
rccc aet r
(7.26)
where:
a: is a shape coefficient