Spring III

This is a simple one dimensional one element example to show how to use *MAT_SPRING_GENERAL_NONLINEAR keyword. Two different curves for describing force versus displacement during loading and unloading are given. Initial yield forces in tension and in compression are specified. Isotropic hardening without strain softening is chosen.

*BOUNDARY_PRESCRIBED_MOTION_NODE
*BOUNDARY_SPC_NODE
*CONTROL_TERMINATION
*DATABASE_BINARY_D3PLOT
*DATABASE_DEFORC
*DATABASE_GLSTAT
*DATABASE_HISTORY_NODE_SET
*DATABASE_NODOUT
*DEFINE_CURVE
*ELEMENT_DISCRETE
*ELEMENT_MASS
*END
*KEYWORD
*MAT_SPRING_GENERAL_NONLINEAR
*NODE
*PART
*SECTION_DISCRETE
*SET_NODE_LIST
*TITLE

  *KEYWORD
  *TITLE
  GENERAL_NONLINEAR
  $---+----1----+----2----+----3----+----4----+----5----+----6----+----7----+----8
  *CONTROL_TERMINATION
     2.0E-01 
  *DATABASE_BINARY_D3PLOT
        0.02
  *DATABASE_DEFORC
     1.0E-04
  *DATABASE_GLSTAT              
   4.000E-04
  *DATABASE_HISTORY_NODE_SET
           1
  *SET_NODE_LIST
           1
           2
  *DATABASE_NODOUT
   0.100E-03
  $---+----1----+----2----+----3----+----4----+----5----+----6----+----7----+----8
  *NODE
         1 0.000000000E+00 0.000000000E+00 0.000000000E+00
         2 1.000000000E+03 0.000000000E+00 0.000000000E+00
  $---+----1----+----2----+----3----+----4----+----5----+----6----+----7----+----8
  *SECTION_DISCRETE  
           1         0
   0.0000000 0.0000000
  $---+----1----+----2----+----3----+----4----+----5----+----6----+----7----+----8
  *MAT_SPRING_GENERAL_NONLINEAR
  $      MID      LCDL      LCDU      BETA       TYI      CYI
           1         6         5       1.0     50.0   -50.0
  $---+----1----+----2----+----3----+----4----+----5----+----6----+----7----+----8
  *PART
  Spring-Damper Part Definition
           1         1         1
  $---+----1----+----2----+----3----+----4----+----5----+----6----+----7----+----8
  *ELEMENT_DISCRETE
         1       1       1       2
  $---+----1----+----2----+----3----+----4----+----5----+----6----+----7----+----8
  *BOUNDARY_SPC_NODE
           1         0         1         1         1         1         1         1
  *BOUNDARY_PRESCRIBED_MOTION_NODE
           2         1         2        99 -1.00E+00
  $---+----1----+----2----+----3----+----4----+----5----+----6----+----7----+----8
  *DEFINE_CURVE
          99
  $
  *DEFINE_CURVE
           6
  $
  *DEFINE_CURVE
           5
  $
  $---+----1----+----2----+----3----+----4----+----5----+----6----+----7----+----8
  *ELEMENT_MASS
         2       1     1.00000E-06
         3       2     1.00000E-06 
  *END