Non linear buckling analysis of column

- October 6, 2017 at 6:58 am
  
  inaamqazi
  Subscriber
  
  1) what would constitute appropriate boundary conditions for a line model . I have applied uy and rotz at one end , ux at the top end, and symmetry boundary conditions on z axis.I have modelled half the length of the column But the non linear solution is terminating even if i increase the substeps significantly from 100 to 1000. I want to consider only geometric non linearity .I am solving in apdl
- October 11, 2017 at 10:23 am
  
  ding
  Subscriber
  
  Can you give me your apdl commands for detailed problems or give me some model pictures ?
- October 11, 2017 at 1:06 pm
  
  inaamqazi
  Subscriber
  
  /NOPR ! Suppress printing of UNDO process
  
  /PMACRO ! Echo following commands to log
  
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  /CLEAR,NOSTART ! Clear model since no SAVE found
  
  ! WE SUGGEST YOU REMOVE THIS LINE AND THE FOLLOWING STARTUP LINES
  
  ! WE SUGGEST YOU REMOVE THIS LINE AND THE FOLLOWING STARTUP LINES
  
  ! WE SUGGEST YOU REMOVE THIS LINE AND THE FOLLOWING STARTUP LINES
  
  ! WE SUGGEST YOU REMOVE THIS LINE AND THE FOLLOWING STARTUP LINES
  
  ! WE SUGGEST YOU REMOVE THIS LINE AND THE FOLLOWING STARTUP LINES
  
  ! WE SUGGEST YOU REMOVE THIS LINE AND THE FOLLOWING STARTUP LINES
  
  ! WE SUGGEST YOU REMOVE THIS LINE AND THE FOLLOWING STARTUP LINES
  
  ! WE SUGGEST YOU REMOVE THIS LINE AND THE FOLLOWING STARTUP LINES
  
  ! WE SUGGEST YOU REMOVE THIS LINE AND THE FOLLOWING STARTUP LINES
  
  ! WE SUGGEST YOU REMOVE THIS LINE AND THE FOLLOWING STARTUP LINES
  
  ! WE SUGGEST YOU REMOVE THIS LINE AND THE FOLLOWING STARTUP LINES
  
  ! WE SUGGEST YOU REMOVE THIS LINE AND THE FOLLOWING STARTUP LINES
  
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  KEYOPT,1,4,0
  
  KEYOPT,1,6,0
  
  KEYOPT,1,7,0
  
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  KEYOPT,1,11,0
  
  KEYOPT,1,12,0
  
  KEYOPT,1,15,0
  
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  MPDATA,PRXY,1,,0.15
  
  SECTYPE, 1, BEAM, RECT, , 0
  
  SECOFFSET, CENT
  
  SECDATA,1500,5000,0,0,0,0,0,0,0,0,0,0
  
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  FILL,1,101,99, , ,1,1,1,
  
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  /ZOOM,1,SCRN,0.341257,-0.888843,0.351177,-0.938430
  
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  E,P51X
  
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  /ZOOM,1,SCRN,0.356137,-0.898760,0.385896,-0.935950
  
  FLST,4,1,2,ORDE,1
  
  FITEM,4,1
  
  EGEN,100,1,P51X, , , , , , , , , , ,
  
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  D,P51X, , , , , ,UY,ROTZ, , , ,
  
  FLST,2,1,1,ORDE,1
  
  FITEM,2,101
  
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  /GO
  
  D,P51X, , , , , ,UX, , , , ,
  
  DSYM,SYMM,Z, ,
  
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  /SOL
  
  FLST,2,1,1,ORDE,1
  
  FITEM,2,101
  
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  F,P51X,FY,-1
  
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  ANTYPE,0
  
  PSTRES,1
  
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  /VIEW,1,1,1,1
  
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  /DIST, 1 ,1.082226,1
  
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  /DIST, 1 ,1.082226,1
  
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  /SOL
  
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  FLST,2,1,1,ORDE,1
  
  FITEM,2,2
  
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  F,P51X,FX,3600000
  
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  /PSF,PRES,NORM,2,0,1
  
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  NEQIT,2100
  
  RESCONTRL,DEFINE,ALL,ALL,-1
  
  /STATUS,SOLU
  
  SOLVE
  
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  /POST1
  
  PLDISP,1
  
  /VIEW,1,1,1,1
  
  /ANG,1
  
  /REP,FAST
  
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  !*
  
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  PLNSOL, U,SUM, 0,1.0
  
  ! SET,LIST,999
  
  SET,,, ,,, ,205
  
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  /POST26
  
  FILE,'file','rst','.'
  
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  SOLU,191,NCMIT
  
  STORE,MERGE
  
  FILLDATA,191,,,,1,1
  
  REALVAR,191,191
  
  /DIST, 1 ,1.082226,1
  
  /REP,FAST
  
  /DIST, 1 ,1.082226,1
  
  /REP,FAST
  
  /DIST, 1 ,1.082226,1
  
  /REP,FAST
  
  !*
  
  NSOL,2,1,U,X, UX_4,
  
  STORE,MERGE
  
  !*
  
  RFORCE,3,1,F,Y, FY_3
  
  STORE,MERGE
  
  FINISH
  
  /AUX12
  
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  NUMVAR,200
  
  FILLDATA,191,,,,1,1
  
  REALVAR,191,191
  
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  NUMVAR,200
  
  FILLDATA,191,,,,1,1
  
  REALVAR,191,191
  
  XVAR,2
  
  PLVAR,3,
  
  FINISH
  
  /POST1
  
  !*
  
  PRNSOL,U,COMP
  
  )/GOP ! Resume printing after UNDO process
  
  )! We suggest a save at this point
- October 11, 2017 at 1:07 pm
  
  inaamqazi
  Subscriber
  
  @ding ..can you share your research gate profile so that we can remain in touch.
  
  With Regards
  
  Inaam