Automatic combinations to Eurocode 0 and 8: how to specify phi for storeys with correlated occupancies and how to group all live loads and maintain the correct coeficients?

Automatic combinations to Eurocode 0 and 8: how to specify phi for storeys with correlated occupancies and how to group all live loads and maintain the correct coeficients?

brisid.isufi
Enthusiast Enthusiast
241 Views
1 Reply
Message 1 of 2

Automatic combinations to Eurocode 0 and 8: how to specify phi for storeys with correlated occupancies and how to group all live loads and maintain the correct coeficients?

brisid.isufi
Enthusiast
Enthusiast

I am having trouble generating automatic combinations to Eurocode 0 and 8. Firstly, I can't find an efficient way to apply the coefficient phi (table 4.2 from EN 1998-1) so that psi_Ei is used in the seismic combinations. Robot seems to use psi_E2 instead of phi × psi_E2:

brisidisufi_0-1721053148033.png

Secondly, I would like to be able to specify all live loads as a leading variable action, but when I group them in the automatic combinations dialog, I get psi = 0.3 for all of them. For example, the relations below don't lead to factor 1.5 being applied for all Q1 to Q4 groups. 

brisidisufi_1-1721053275952.png

Could you please explain how to correctly define combinations according to Eurocode?

 

0 Likes
242 Views
1 Reply
Reply (1)
Message 2 of 2

DennisVDijk
Advocate
Advocate

Hello brisid.isufi,

 

Maybe you can try to make your combination in excel and paste the cells from excel into the combination table.

Loads --> Combination table, tab: edit:

DennisVDijk_0-1721221791138.png

 

you can integrate fi = fi2 x rho = 0,3 * 0,6 = 0,18 at the column, coefficient for live loads.

 

excel table:

DennisVDijk_1-1721222069857.png

this way you stay in control of the applied combinations and values.

 

 

Kind regards,

Dennis van Dijk
Structural engineer
www.ibureaunoordwolde.nl
0 Likes