If the topslab has its own groupnumber, you could use “grp facd” (in this special loadcase) as difference:
grp no - facd 0; grp no “top” facd “special value”
lc no “waterpressure-No.”
AREA REF QGRP 'Top' Proj 'yy' ...
But this don’t work in summary-loadcases with FACD also in LC.
When your outer walls are thick or the pressure high, you should probably calculate with real loadareas (loads “behind” the systemlines / the half wallthickness).
sorry, but I’m not sure I understand your comments.
My topslab has its own group number (secondary group) ‘Top’.
But do you mean that the areas where the thickness varies should have separate group numbers?
I have considered adding negative loads there based on the thickness, but I was hoping for a better solution.
‘top’ alone / the entire topslab is good, you don’t need extra groups / it is better without such.
(Yet to “grp no top facd …”: a additional disadvantage is, this works only for pressure in the system-deadload-direction.)
The system-width is smaller then the real outer limits. By calculation with system-width you undercharge the overall-pressure / the vertical load in the outer walls.
Can you give an example of how you would apply this factor? I still don’t quite follow.
Also, when you say it only works in the deadload direction, does that mean I can’t use it in the base slab, as I need to apply it in the opposite direction there?
ahh yes, this has been taken into account with stiff members from center line to the outer edge of the element, but I didn’t show it in the drawings as I figured that would only confuse
+prog sofimsha urs:2
head test
syst spac gdiv 1000
node 1,02,03 x 0,2,5 y 0 z 0,-0.50,-0.50
11,12,13 x = y 3 z =
grp 01 titl 'top'
quad - 1 11 12 2 m 5 n 6 t1 1.50[m] t2 1.50[m] t3 0.50[m] t4 0.50[m] c 20 ct 1
- 2 12 13 3 m - n 7 t 0.50[m] c = ct =
end
+prog sofiload urs:3
lc no 19 titl 'preparation 10 kN/m² lower edge'; quad grp 01 p (10+0.50*25) $ target: 10; additional deadload of the "main slab"
end
+prog ase urs:4
lc 19; end
grp - facd 0; grp no 01 facd -1
lc 20 titl 'eff. 10 kN/m²'; lcc 19
end
I think it works, but maybe, you don’t see it, because you see not all loads.
Here is my input for the output:
PROG WING
$ GRAPHIC-Dokument (Version 2022- 6.00 Build 0)
HEAD $Mittlere QUAD-Elementdicke
PAGE UNII 0 $ Standard-Einheitenset
CTRL OPT GSTR VAL DEFA
CTRL OPT REPR VAL YES
$ DB NR 1 BEZ "xxxx.cdb"
$ Grafik 1 | Bild 1 | Layer 1 : Mittlere QUAD-Elementdicke
PAGE LANO 0
SIZE TYPE URS SC 0
SIZ2
AND POSI 1 POSL 0 POSR 100 POSD 0 POSU 100
SCHH H6 -0.160000
SCH2 DIRE STAN
LC NO 20 DESI 1
BOX
GRP NUMB KNOT OPTI OFFL
GRP NUMB FKNO OPTI OFFL
GRP NUMB EDGE OPTI OFFL
GRP LC YES
VIEW TYPE DIRE X 0 Y -1 Z 0 AXIS POSZ ROTA 0
DEFO TYPE NO EXPO 0 SMOV NO
SELE NUMB 0
STRU NUME T NUMN QUAD FILL NO REPR DVEC UNIT LFAC SCHH NO
$ Grafik 1 | Bild 1 | Layer 2 : Alle Lasten LF: 20
AND
SCHH H6 0.370000
SCH2 DIRE STAN EDGE NO PREF NO PROP 'B'
QUAD TYPE DSGN COMT NO
LOAD TYPE ALL UNIT DEFA SCHH YES SING VECT FILL NO REPR DREP ETYP ALL GTYP INP
END
And this are the loadsumms (in global z):
LC 19: -341.7 kN
LC 20: -74.5 kN
The grp-fcd should work without backlash to AREA-loads respectively revers. Also by AREA and WITH. Although i had sometimes programm-troubles with WITH.
Or it is possibly your deadload-direction “yy” (but it must not).
