Question about COMB in AQB

SOFiSTiK
1

The questions are related to is the Sofistik built-in example attached as below
csm31_design_aashto_suma.dat (58.9 KB), which is located in
C:\Program Files\SOFiSTiK\20XX\SOFiSTiK 20XX\csm.dat\english\more\

Below is the fragment of the whole code

+PROG AQB urs:27
HEAD Manual check - Interpretation
ECHO SECT,LC,COMB,FORC,REIN,STRE NO
ECHO TABS 2 $ 1+2 = print all tendons separately
  CTRL SVRF   1.00000 $ take into account reinforcement for C+S
  CTRL WARN  2063     $ to avoid warning 2063 (COMB MAXD D for design works ! )
$
$ loadcases to be used:
#include "$(project)_csmlf.dat"  $ AQB LC-loadcase definition of construction stages 'GPC'

$ other variable actions:
LC       TYPE 'LB  '  CST #cslast  $    'Total life load LB'
LC       TYPE 'T   '  CST #cslast  $    'Temperature'
LC       TYPE 'W   '  CST #cslast  $    'wind'
LC       TYPE 'ZF  '  CST #cslast  $    'possible settlement SLS'
LC       TYPE 'SF  '  CST #cslast  $    'probable settlement ULS'

$ beams to be used:
BEAM 1105 X 0.000 CS auto
$ BEAM 2116 X 0.000 CS auto

$ Combinations:
$ *************************************************************
$ stresses in single loadcases:  See first CSM run - check print  !!!!!!!!!!!!
                                                                              
$ ==================================== linear stresses    STRE ==============================================
COMB SUM LC1 D TITL   'sum_D'
COMB SUM LC1 PS TITL  'sum_PS'
COMB SUM LC1 CR TITL  'sum_CR'

COMB MAX MY LC1 'LB'        TITL 'max MY LB  '
COMB MIN MY LC1 'LB'        TITL 'min MY LB  '
COMB MAX MY LC1 'T'         TITL 'max MY T  '
COMB MAX MY LC1 'ZF'        TITL 'max MY ZF '
COMB MAX MY LC1 'SF'        TITL 'max MY SF '
COMB MAX MY LC1 'W'         TITL 'max MY W  '

$ ==================================== SLS design : linear stress (uncracked) on given force (N,MY)

COMB MAX  MY LC1 D 1.00  LC2 PS 1.00  LC3 CR 1.00  LC4 LB 1.00 LC5 T 1.00 LC6 ZF 1.00 LCST 8101  TITL 'SLS+ D+P+C+LB+T+ZF STRE'
COMB MIN  MY LC1 D 1.00  LC2 PS 1.00  LC3 CR 1.00  LC4 LB 1.00 LC5 T 1.00 LC6 ZF 1.00 LCST 8102  TITL 'SLS- D+P+C+LB+T+ZF STRE'
STRE K $ prints linear stresses of previous combinations

Here are my questions
Q1: As for

COMB SUM LC1 D TITL   'sum_D'
COMB SUM LC1 PS TITL  'sum_PS'
COMB SUM LC1 CR TITL  'sum_CR'

Does it mean adding D, PS and CR that occurred in CSM into LC1?

Q2: If the answer to Q1 is yes, then according to CSM

+PROG CSM URS:87
HEAD Construction sequence
CTRL DL  AUTO  $ Dead load of gamma automatically
CTRL STOR 1    $ create 7000 AQB result loadcases = including tendon creep and shrinkage losses
$ CTRL GPCS 1    $ GPC-separated = more accurate in case of removing supports
$
CS 10 TYPE D_1  TITL 'D_1'
CS 11 TYPE PS   TITL 'Prestress PS               '
CS 15 TYPE CR_1 TITL 'Creep till superimpose D_2 '   T    40
CS 18 TYPE D_1  TITL 'additional D_1' $ to make SUMA more clear
CS 20 TYPE D_2  TITL 'D_2, Asphalt, capping      '
CS 25 TYPE CR_1 TITL 'Creep till traffic opening '   T    40
CS 34 TYPE ZC   TITL '20 % UDL'
CS 35 TYPE CR_2 TITL 'C+S t-infinite             '   T 365*100   NCRE 2

Since only “D_1” and “D_2” are applied in CSM, how come the “D” instead of “D_1” and “D_2” was added into LC1 in Q1?

Q3: As for this command, Does it mean getting mx MY from ‘LB’, then defining it as LC1? If so, the LC1 will replace the previous LC1 (=D+PS+CR)?

COMB MAX MY LC1 'LB'        TITL 'max MY LB  '
2

Hi,
regarding Q1: Yes. You can simply define ECHO FULL EXTR in AQB and check Reportbrowser output, there you find exactly which load cases are used.

Q2: Depending from the intention you can define only D => then all load cases of action D are taken with the same factor. If you define D_1 oder D_2 only load cases of action D catogary 1 or 2 are taken. If you would choose both with LC1 D_1 and LC2 D_2 they are taken with own factors.
Again: With ECHO FULL EXTR you can check the effect.

Q3: Yes. And each COMBination is independent of another.

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