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Hi, I have for the last few weeks dedicated a serious amount of time producing an Excel calculation table for EN 15913. I have managed to get so far but for some reason can not calculate FGΔ. Can anyone tell me what the max all I≠0 means in the calculation as im sure I am missing a trick here. Thanks 

Sorry its 15911,got confused with 134453 Annex G. 

hartsa (Mechanical) 
16 Sep 09 3:19 
Hi,
I too spent quite a long time few years back in producing excel calcs according to EN134453 annex G. Nowadays there are commercial softwares such as VVD that does these calculations.
But calculating FGΔ according to EN15911 (equation 51) means that you have to calculate FGΔ in every subsequent condition and then the max value calculated is FGΔ.
For example: Subsequent conditions 1, 2, ...n
FGΔ1=(FG1min x YG1+(FQ1 x YQ1 +(FR1 x YR1  FR0 x YR0)+ ΔU1)) / YG0
FGΔ2=(FG2min x YG2+(FQ2 x YQ2 +(FR2 x YR2  FR0 x YR0)+ ΔU2)) / YG0
FGΔn=(FGnmin x YGn+(FQn x YQn +(FRn x YRn  FR0 x YR0)+ ΔUn)) / YG0
and finally
FGΔ = max(FGΔ1 ; FGΔ2 ; ... ; FGΔn)
Hope this helps...
Regards Harri


If possible can some one give me some further clarification on the following from EN15911:
When checking the admissible loads in Section 6 if for example the conditions in the table state that ψZ=ψmax is ψmax calculated at Js=+1, ks=+1 and km+1. Also if the conditions state that ψZ=ψopt is ψopt calculated at Js=0, ks=0 and km=0. Thanks a lot for any help.


hartsa (Mechanical) 
18 Sep 09 6:09 
Hi, Calculation sequence is presented after table 2 in the standard EN15911. When calculating for example ψmax, calculate ψmax with the equation 82 using js=+1, km=+1 and ks=+1. ψmin is calculated with js=1, km=1 and ks=+1 and so on. Then you have to determine the value of jm (equation 80) and ψopt (83). Finally for example if jm=+1 and ψopt >= ψmax, then km=+1 and ψz = ψmax. I attached some example from calculation of integral flanges. I think that this was very useful when I did my calculations. It has all the required initial data to begin the calculations like dimensions, materials, etc. And there are results so that it was easy to compare my own calculations and this example. It should be reliable, one of our NB inspectors gave it to me. Regards Harri 

Thank you very much for an informative response once again and especially for the attached example which I will use to perform checks. I suspected that to be the case for ψz = ψmax, however my confusion came in the for of equation 84, which has no explanation but indicates that ψopt should equal ψ(0,0,0)??? I have produced my model after three weeks and just now checking that I have removed all potential errors. Thanks once again for your help.
Regards,
James 



