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CFVR3704 - Initial stresses on 3D Model

Initial stresses on a 3D Model with irregular mesh.

A prism model is free meshed with tetrahedral-shaped elements. The model is rotated about a local coordinate system. Initial stresses and gravity are applied.

Element types used in the model: SOLID185

Needed CivilFEM Modules:
Geotechnical Module
Bridges and Civil Non Linearities Module
Advanced Prestressed Concrete Module

The example cannot be launched on an educational license.
KEYWORDS
Geotechnics

Model Statistics
Number of elements 6868
Number of nodes 1562
Number of civil materials 1
Number of cross sections 0
Number of shell vertices 0

Log file: CFVR3704.DAT


FINISH
~CFCLEAR,,1
~CFACTIV,GETC,Y
~UNITS,SI
*AFUN,DEG

/DELETE,cfvr3704,ist
NomFile='CFVR3704'
/TITLE,%NomFile%,Initial stresses. 3D Model
 
! parameters
! ----------
RXY  = 30. ! Euler angles
RYZ  = -20.
RZX  = 55.
DEPT = 1. ! depth of the prism
NDIV = 30 ! number of divisions of the lines parallel to the axis Z 
NEL  = 4  ! number of elements where to check values
 
! element types
! -------------
/PREP7
ET,1,SOLID185

! materials
! ---------
~CFMP,1,LIB,SOIL,,GC
~CFGET,GAM,MATERIAL,1,DATGEN,GAM
~CFGET,K0,MATERIAL,1,SOIL,K0
 
! solid model and mesh
! --------------------
ESIZ = DEPT/NDIV
CLOCAL,11,0,,,,RXY,RYZ,RZX
TMP = 5*ESIZ
K,1,0.,0.,0.
K,2,TMP,0.,0.
K,3,TMP,TMP,0.
K,4,0.,TMP,0.
K,5,0.,0.,DEPT
K,6,TMP,0.,DEPT
K,7,TMP,TMP,DEPT
K,8,0.,TMP,DEPT

V,1,2,3,4,5,6,7,8
MSHAPE,1,3D
LESIZE,ALL,ESIZ
VMESH,ALL
NROTAT,ALL

! DATA CHECK
! ----------

NCOMP= NEL*6
NCOMP_CH = 0
*DIM,LABEL,CHAR,NCOMP,1
*DIM,LABEL_CH,CHAR,NCOMP_CH,1
*DIM,VALUE,,NCOMP,3
*DIM,VALUE_CH,CHAR,NCOMP_CH,3
*DIM,TOLER,,NCOMP,2

! rotation matrix
! ---------------
*DIM,ROT,ARRAY,3,3
CSXY      = COS(RXY)
SNXY      = SIN(RXY)
CSYZ      = COS(RYZ)
SNYZ      = SIN(RYZ)
CSZX      = COS(RZX)
SNZX      = SIN(RZX)
CSXY_SNYZ = CSXY*SNYZ
SNXY_SNYZ = SNXY*SNYZ
ROT(1,1)  =  CSXY*CSZX - SNXY_SNYZ*SNZX
ROT(2,1)  =  SNXY*CSZX + CSXY_SNYZ*SNZX
ROT(3,1)  = -CSYZ*SNZX
ROT(1,2)  = -SNXY*CSYZ
ROT(2,2)  =  CSXY*CSYZ
ROT(3,2)  =  SNYZ
ROT(1,3)  =  CSXY*SNZX + SNXY_SNYZ*CSZX
ROT(2,3)  =  SNXY*SNZX - CSXY_SNYZ*CSZX
ROT(3,3)  =  CSYZ*CSZX

! correct data 
! ------------
*DIM,IEL,,NEL ! elements where to check values
*DIM,SIG_L,,3,NEL
IEL(1) = 1,5,624,891

J = 1
*DO,I,1,NEL
  SIG_L(3,I) = -GAM*(DEPT - (CENTRX(IEL(I))*ROT(1,3) + CENTRY(IEL(I))*ROT(2,3) + CENTRZ(IEL(I))*ROT(3,3)))
  SIG_L(1,I) = K0*SIG_L(3,I)
  SIG_L(2,I) = SIG_L(1,I) 

  TMP  = SIG_L(1,I)*ROT(1,1)
  TMP1 = SIG_L(2,I)*ROT(1,2)
  TMP2 = SIG_L(3,I)*ROT(1,3)
  VALUE(J,1)   = ROT(1,1)*TMP + ROT(1,2)*TMP1 + ROT(1,3)*TMP2 ! SXX
  VALUE(J+3,1) = ROT(2,1)*TMP + ROT(2,2)*TMP1 + ROT(2,3)*TMP2 ! SXY
  VALUE(J+5,1) = ROT(3,1)*TMP + ROT(3,2)*TMP1 + ROT(3,3)*TMP2 ! SXZ
  TMP  = SIG_L(1,I)*ROT(2,1)
  TMP1 = SIG_L(2,I)*ROT(2,2)
  TMP2 = SIG_L(3,I)*ROT(2,3)
  VALUE(J+1,1) = ROT(2,1)*TMP + ROT(2,2)*TMP1 + ROT(2,3)*TMP2 ! SYY
  VALUE(J+4,1) = ROT(3,1)*TMP + ROT(3,2)*TMP1 + ROT(3,3)*TMP2 ! SYZ
  VALUE(J+2,1) = ROT(3,1)*SIG_L(1,I)*ROT(3,1) + ROT(3,2)*SIG_L(2,I)*ROT(3,2) + ROT(3,3)*SIG_L(3,I)*ROT(3,3) ! SZZ
  J = J + 6
*ENDDO

! obtained data 
! -------------
/SOLU

DA,1,UZ
DA,2,UY
DA,5,UX
SFGRAD,PRES,11,Z,DEPT,-GAM*K0
SFA,3,,PRES,0.
SFA,4,,PRES,0.
~TIS,cfvr3704,ist,Z
ACEL,9.8*ROT(1,3),9.8*ROT(2,3),9.8*ROT(3,3)
INISTATE,READ,cfvr3704,ist

ERESX,NO
NROPT,FULL
SOLVE

/POST1
SET,LAST

ETABLE,,S,X
ETABLE,,S,Y
ETABLE,,S,Z
ETABLE,,S,XY
ETABLE,,S,YZ
ETABLE,,S,XZ
J = 1
*DO,I,1,NEL
  *GET,VALUE(J  ,2),ETAB,1,ELEM,IEL(I)
  *GET,VALUE(J+1,2),ETAB,2,ELEM,IEL(I)
  *GET,VALUE(J+2,2),ETAB,3,ELEM,IEL(I)
  *GET,VALUE(J+3,2),ETAB,4,ELEM,IEL(I)
  *GET,VALUE(J+4,2),ETAB,5,ELEM,IEL(I)
  *GET,VALUE(J+5,2),ETAB,6,ELEM,IEL(I)
  J = J + 6
*ENDDO

! results comparison
! ----------------------------------------------------------------------
EREL = 1.0
*DO,I,1,NCOMP
  TMP = EREL*ABS(VALUE(I,2) - VALUE(I,1))
  TOLER(I,1) = TMP 
  TOLER(I,2) = TMP
*ENDDO

COMPARA.MAC

Results

LabelTargetCivilFEMRatioTolerance
-6363.1 -6256.71.017 106.4
-6187.4 -6159.91.004 27.48
-5977.6 -5937.71.007 39.96
-1640.8 -1613.61.017 27.3
-1446.7 -1452.70.996 6.045
-1526.2 -14951.021 31.23
-6236.4 -6251.60.998 15.22
-6064.2 -60571.001 7.22
-5858.7 -5842.31.003 16.37
-1608.2 -1612.80.997 4.653
-1417.9 -14081.007 9.858
-1495.8 -1502.10.996 6.269
-8802.5 -8855.10.994 52.63
-8559.4 -8631.10.992 71.67
-8269.3 -8325.30.993 55.96
-2269.9 -2295.40.989 25.54
-2001.3 -2026.70.987 25.42
-2111.3 -2130.50.991 19.18
-12242 -122560.999 14.62
-11904 -119360.997 32.51
-11500 -115330.997 32.85
-3156.8 -3164.20.998 7.433
-2783.3 -2804.50.992 21.25
-2936.3 -2951.20.995 14.98


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