Kmod for timber structures

Hello all,

How can i get AQB to include Kmod factors for timber structures?

I have both tried defining my load type as (VT) in SOFiLOAD, e.g. LC 1 TYPE (VT), but also in AQB:

+PROG AQB
HEAD timber design
BEAM
LC 1 TYPE (VT)
STRE E H
END

But it is not including Kmod in the stress limits in the report. E.g. bending stress limit is just calculated as fm/γM = 24MPa/1.35 = 17.78MPa

I have specified the following in AQUA:

NORM EN 1995-2004
TIMB 1 C 24:2 SCM 1.35

Regards
Mads Nielsen

Dear Mr Nielsen

Have you seen the TEDDY example about timber design?

TEDDY > File > Examples > aqb > english > aqb1_3_timber_design.dat

The kmod factor is not included within the stress limits, because you could have different times under load for different loadcases or combinations. As a result you have different kmod values and different stress limits for different loadcases. This makes it difficult for AQB to use the correct stress limit for the correct loadcase (combination). The solution for this problem is, to divide the design forces by the kmod factor.

You can check this behaviour by comparing an AQB calculation of a design combination (COMB TYPE DESI) with a AQB calculation TYPE H

+prog MAXIMA
head
COMB 11 DESI BASE 3100

end

+prog AQB
head
LC ( D)
STRE E H
end


+prog MAXIMA
head
COMB 11 DESI TYPE ST BASE 3100

end

+prog AQB
head
LC ( ST)
STRE E H
end

The differnce between theese two calculations is:
3,05 / 0,9 = 3,39

Best regards
Frederik Höller
Your SOFiSTiK Support Team

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