Notional horizontal forces (NHFs) (British Standards)
NHF’s are automatically derived from the loadcases within the current combination, their magnitude being calculated in accordance with BS5950 cl 2.4.2.3 as 0.5% of the factored vertical load that passes through any beam/column intersection in the structure.
Settings that control the NHF percentage can be adjusted from .
They are applied to the structure in the building directions 1 and 2 as follows:
- NHF Dir1+
- NHF Dir1-
- NHF Dir2+
- NHF Dir2-
The net result is that any combination is able to have up to 2 Notional Loads applied within it - one from Dir1 (+ or -) and one from Dir2 (+ or -). Note however, that Dir1+ can not be added with Dir1- (and similarly Dir2+ can not be added with Dir2-).
Once you have created NHF combinations and performed the analysis, you can view the magnitude of the notional loads from the project workspace. You can also display their magnitude and direction graphically in a results view.