Sustained Live Load 1

[slickdeals]

All:
Is there any codal recommendation on the percentage of live load that should be used as "sustained" live load in calculating long term deflections?

Online search yields results from 25-30%, sometimes going up to 50%. Any literature that has good recommendations?

Thanks

 

[DST148]

As per commentary of ASCE 7-05 - For serviceability limit states involving creep, settlement, or similar long-term or permanent effects, the suggested load combination is:
D + 0.5L . The dead load may include that portion of the dead load that occurs following attachment of nonstructural elements.
AISC Design Guide 3 for Serviceability gives the same load combination of D + 0.5L for long term effects.

 

[ishvaaag]

See Section 4.3 in attachment...

 

[rapt]

Eurocode 1991 Part? (not sure which one gives combination factors) defines different values for different building types.

 

[Guest262653]

Check EN1990 - Table A1.1 (page 49). For quasi-permanent load combinations use the psi2 values for the type of live load you are considering.

 

[DST148]

avscorreia - Could you please provide the load factors to be used for quasi-permanent load combinations per EN1990 for typical occupancies like residential and offices?

 

[slickdeals]

It is 0.3.