Now, Staad.Pro includes the option of Reducible Live Load by UBC/IBC. But the formula included is 16-23 instead of 16-22.
Also, Staad uses equation 16-23 for load type Live and type Roof Live, instead of using section 1607.11 for Roof Live and equation 16-25.
For other codes, Mexican code NTC, also considers live load reduction but using a different equation.
My idea is one of two options:
The user can customize a formula using simple Excel-like operators, where Area is calculated automatically like it does now.
Add a load parameter for live load and roof live load where, similar to Design Parameters, you can just input the desire coefficient and then assign that coefficient to the member (beam, column). This way, user calculates the coefficient by hand but is directly clear which element is affected.
So, for a 1 kN/m² uniform load, I could assign a 0.6 coefficient for columns, 0.8 coefficient for girders, and 1.0 for joists.
Seconded, some other suggestions to this end (I posted the same idea redundantly):
There is currently no efficient way to consider the live load reduction factor in STAAD.Pro. It would be fantastic to add a parameter to the design section (e.g., under CSA S16-19 or AISC 360-16) to consider a live load reduction on an element by element basis. This would be manually calculated by the analyst until someone at Bentley can figure out how to determine tributary area for an element based perhaps on the floor load command (easy example for columns, TA = axial load/input floor live load (assumes same uniform load on each floor, but analysts could separate occupancy live loads into different load cases to make this work at least in accordance with the NBCC); for girders, TA = [shear 1 + shear 2] / input floor live load).
Thank you for posting your idea. We have an internal review planned to review the current live load reduction implementation and documentation. Following this we can consider the best action to take.