Snow loads (Eurocode)
Loadcases set up by the snow wizard
In the Snow wizard (Eurocode) you choose the snow loadcases to be set up from the following list:
-
Snow Load - Case A - 1) Undrifted
-
Snow Load - Case A - 2) Drifted *
-
Snow Load - Case B1 - 1) Undrifted Snow Load - Case B1 - 2) Drifted *
-
Snow Load - Case B1 - 3) Undrifted (Acc)
-
Snow Load - Case B1 - 4) Drifted (Acc) *
-
Snow Load - Case B2 - 1) Undrifted
-
Snow Load - Case B2 - 2) Drifted *
-
If any drifts from Annex B are selected
-
Snow Load - Case B2 - 3) Drifted (Annex B) (Acc) *
-
-
Snow Load - Case B3 - 1) Undrifted
-
Snow Load - Case B3 - 2) Drifted *
-
Snow Load - Case B3 - 3) Undrifted (Acc)
-
If any drifts from Annex B are selected
-
• Snow Load - Case B3 - 4) Drifted (Annex B) (Acc) *
-
Note: For cases marked * - the number of
cases actually set up will depend on the number of wind directions that are asked
for.
Note: The Eurocode / National Annex
recommends which loadcases to generate.
Note: All loads and lengths of loads are
assumed to act on a horizontal projection of the roof surface.
Once set up these loadcases are standard loadcases so you can include them in combinations in the normal manner.
Undrifted loadcases
Any undrifted loadcases that have
been set up in the Snow Wizard are automatically populated with uniform loading on completion of the wizard
Drifted loadcases
All drifted loadcases that have been
set up in the Snow Wizard would need to be have their snow loads manually applied on completion of the
wizard. 
Definition of psi factors for snow and snow drift loadcases
In the Loadcase dialog when a snow, snow drift, or ice loadcase is selected, the default values of Ψ0, Ψ1 and Ψ2 are displayed. These vary depending on the National Annex being worked to. The values can be edited if required. See “psi factors”
Note: Snow drift loads are considered
to be accidental loadcases and are combined in the Accidental
combinations.