Lee's Frame buckling Problem — Welcome to LS-DYNA Examples

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A framed structure deforming under a load applied on one node. The frame is pinned to ground at two nodes. Arc-length method is used to capture the post-buckling behavior of the structure. Example 7 from Introductory Manual for LS-DYNA Users by James M. Kennedy.

Keywords
*BOUNDARY_SPC_NODE
*CONTROL_IMPLICIT_AUTO
*CONTROL_IMPLICIT_GENERAL
*CONTROL_IMPLICIT_SOLUTION
*CONTROL_TERMINATION
*DATABASE_BINARY_D3PLOT
*DATABASE_GLSTAT
*DATABASE_HISTORY_NODE
*DATABASE_MATSUM
*DATABASE_NODAL_FORCE_GROUP
*DATABASE_NODFOR
*DATABASE_NODOUT
*DEFINE_CURVE
*ELEMENT_BEAM
*END
*KEYWORD
*LOAD_NODE_POINT
*MAT_ELASTIC
*NODE
*PART
*SECTION_BEAM
*SET_NODE_LIST
*TITLE
Reduced Input
*KEYWORD
*TITLE
Lee's Frame Buckling Problem
*CONTROL_IMPLICIT_AUTO
         1        20         5 1.000e-09
*CONTROL_IMPLICIT_GENERAL
         1  0.003000         2       100         2         1
*CONTROL_IMPLICIT_SOLUTION
         6        30        15 1.000e-06 1.000e-05 1.000e-05  0.990000  1.000000
         2         1         1         2
         0         1       0.0         1         2
*CONTROL_TERMINATION
  1.000000         0       0.0       0.0       0.0
*DATABASE_GLSTAT
  0.001000         1
*DATABASE_MATSUM
  0.001000         1
*DATABASE_NODFOR
1.0000e-04         1
*DATABASE_NODOUT
1.0000e-04         1
*DATABASE_BINARY_D3PLOT
  0.010000         0         2
*DATABASE_NODAL_FORCE_GROUP
         1
*DATABASE_HISTORY_NODE
        56        36         1
*DEFINE_CURVE
         1         0  1.000000  1.000000       0.0       0.0
                 0.0                 0.0
          1.00000000       5.0000000e+04
*ELEMENT_BEAM
*NODE
*BOUNDARY_SPC_NODE
*PART
         1         1         1
*SECTION_BEAM
         1         1  0.830000         5         0       0.0
  0.030000  0.030000      0.02      0.02
*MAT_ELASTIC
         1  7850.0007.1740e+10       0.0       0.0       0.0       0.0
*LOAD_NODE_POINT
        56         2         1 -1.000000
*SET_NODE_LIST
         1       0.0       0.0       0.0       0.0
         1         6        36        56
*END
Figures

figure_screw_0ms.png

figure_screw_60ms.png

Animated Result

buckling_ani.gif

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