# Wood Post — Welcome to LS-DYNA Examples

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A wooden post with a hole is hit by a bar and is supposed to snap-off. The bar is rigid and extra mass is added via density to give it enough energy to snap the post.

## Keywords

```*BOUNDARY_SPC_NODE
*CONTACT_AUTOMATIC_SINGLE_SURFACE
*CONTROL_ENERGY
*CONTROL_TERMINATION
*DATABASE_BINARY_D3PLOT
*DATABASE_BINARY_D3THDT
*DATABASE_EXTENT_BINARY
*DATABASE_GLSTAT
*DATABASE_HISTORY_NODE
*DATABASE_MATSUM
*DATABASE_NODOUT
*DATABASE_RBDOUT
*DATABASE_SLEOUT
*ELEMENT_SHELL
*ELEMENT_SOLID
*END
*INITIAL_VELOCITY_GENERATION
*KEYWORD
*MAT_PIECEWISE_LINEAR_PLASTICITY
*MAT_RIGID
*NODE
*PART
*SECTION_SHELL
*SECTION_SOLID
*TITLE```

## Reduced Input

```  *KEYWORD
*TITLE
A wooden post, with a hole, is hit by a bar and is supposed to snap-off.
\$
\$\$  The bar is rigid and extra mass (via density) is added to
\$\$  give it enough energy to snap the post.
\$
\$\$  This model uses constant stress solid element formulation (default: type 1)
\$\$  for the posts and default hourglass viscosity type 1.
\$
\$
\$  John D. Reid  2/6/95, 3/11/98, 2/7/00
\$
\$  Units: mm, kg, ms, kN, GPa, kN-mm
\$
\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$
\$
\$\$\$\$  Control Ouput
\$
\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$
\$
\$...>....1....>....2....>....3....>....4....>....5....>....6....>....7....>....8
\$
*CONTROL_TERMINATION
\$   endtim    endcyc     dtmin    endeng    endmas
7.00
\$
*CONTROL_ENERGY
\$     hgen      rwen    slnten     rylen
2         2
\$
*DATABASE_BINARY_D3PLOT
\$       dt       lcdt
0.5
\$
*DATABASE_EXTENT_BINARY
\$    neiph     neips    maxint    strflg    sigflg    epsflg    rltflg    engflg

\$   cmpflg    ieverp    beamip
1
\$
*DATABASE_BINARY_D3THDT
\$       dt       lcdt
999999
\$
\$
*DATABASE_GLSTAT
\$       dt
0.10
\$
*DATABASE_MATSUM
\$       dt
0.10
\$
*DATABASE_NODOUT
\$       dt
0.10
\$
*DATABASE_HISTORY_NODE
\$      id1       id2       id3       id4       id5       id6       id7       id8
758
\$
*DATABASE_RBDOUT
\$       dt
0.10
\$
*DATABASE_SLEOUT
\$       dt
0.10
\$
\$
\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$
\$
\$\$\$\$  Contacts - Sliding Interfaces
\$
\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$
\$
*CONTACT_AUTOMATIC_SINGLE_SURFACE
\$     ssid      msid     sstyp     mstyp    sboxid    mboxid       spr       mpr
0         0                                                 1         1
\$       fs        fd        dc        vc       vdc    penchk        bt        dt

\$      sfs       sfm       sst       mst      sfst      sfmt       fsf       vsf

\$
\$
\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$
\$
\$\$\$\$  Boundary Conditions
\$
\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$
\$
\$...>....1....>....2....>....3....>....4....>....5....>....6....>....7....>....8
\$
*BOUNDARY_SPC_NODE
\$      nid       cid      dofx      dofy      dofz     dofrx     dofry     dofrz
\$
\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$
\$
\$\$\$\$  Initial Conditions
\$
\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$
\$
\$...>....1....>....2....>....3....>....4....>....5....>....6....>....7....>....8
\$
*INITIAL_VELOCITY_GENERATION
\$      sid      styp     omega        vx        vy        vz
3         2               26.82       0.0       0.0
\$       xc        yc        zc        nx        ny        nz     phase

\$
\$
\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$
\$
\$\$\$\$  Define Parts and Materials
\$
\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$
\$
\$...>....1....>....2....>....3....>....4....>....5....>....6....>....7....>....8
\$
\$
\$\$\$ Part    3    shell: bar
\$
\$\$\$ Part    4    solid: lower_post
\$
\$\$\$ Part    5    solid: upper_post
\$
\$
\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$   Bar
\$
\$\$  Bar - Rigid, constrained to translate only in the x-direction
\$
*PART
bar
\$      pid       sid       mid     eosid      hgid      grav    adpopt
3         1         1
\$
\$
*MAT_RIGID
\$      mid        ro         e        pr         n    couple         m     alias
1 0.143E-02     200.0      0.33
\$
\$      cmo      con1      con2
1.0         5         7
\$
\$   lco/a1        a2        a3        v1        v2        v3

\$
\$
*SECTION_SHELL
\$      sid    elform      shrf       nip     propt   qr/irid     icomp
1         2              3.0000
\$       t1        t2        t3        t4      nloc
1.54      1.54      1.54      1.54
\$
\$
\$
\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$   Post
\$
\$
*PART
\$      pid       sid       mid     eosid      hgid      grav    adpopt
\$
lower_post
4         2         2
upper_post
5         2         3
\$
\$
*MAT_PIECEWISE_LINEAR_PLASTICITY
\$      mid        ro         e        pr      sigy      etan      eppf      tdel
2 0.499E-06     11.37      0.32    0.0468                0.11
\$  Cowper/Symonds Strain Rate Parameters
\$        C         p      lcss      lcsr

\$  plastic stress/strain curves
0.000     0.250
0.0468    0.0470
\$
\$
*MAT_PIECEWISE_LINEAR_PLASTICITY
\$      mid        ro         e        pr      sigy      etan      eppf      tdel
3 0.499E-06    110.37      0.32    0.0468                0.25
\$  Cowper/Symonds Strain Rate Parameters
\$        C         p      lcss      lcsr

\$  plastic stress/strain curves
0.000     0.250
0.0468    0.0470
\$
\$
*SECTION_SOLID
\$      sid    elform
2
\$
\$
\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$
\$
\$\$\$\$  Define Nodes and Elements
\$
\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$\$
\$
\$...>....1....>....2....>....3....>....4....>....5....>....6....>....7....>....8
\$
*END```