Two overlapping plates are connected using three spotwelds. The plates are pulled apart until the spot welds reach the defined failure condition.
*CONSTRAINED_SPOTWELD Spot Weld Secures Two Plates LS-DYNA Manual Section: *CONSTRAINED_SPOTWELD Additional Sections: *BOUNDARY_PRESCRIBED_MOTION_SET *DATABASE_CROSS_SECTION_PLANE *DATABASE_CROSS_SECTION_SET Example: Spot Weld Secures Two Plates Filename: constrained.spotweld.plates.k Description: Two overlapping plates are connected using three spotwelds. The plates are pulled apart until the spot welds reach the defined failure condition. Model: The two plates measure 80*40*1 mm3 and are defined with S/R Hughes-Liu shell elements to control hourglassing. The location of the spotwelds connecting the two plates is in the center of the overlapping section. One end of the plate has fixed constraints and the other end of the other plate has linearly increasing displacement. Input: The nodal point cards contain the boundary conditions at one end of the plate (*NODES). *BOUNDARY_PRESCRIBED_MOTION_SET defines the nodal motion of the end of the other plate. Massless beams simulate the connection between the plates at three locations (*CONSTRAINED_SPOTWELD). The definitions include failure as a function of the axial and shear force. The ASCII file swforc contains the axial and shear forces on the spotweld (*DATABASE_SWFORC). A cross section is defined through each of the plates using two different techniques (*DATABASE_CROSS_SECTION_PLANE, *DATABASE_CROSS_SECTION_SET). Forces and moments through the cross sections are stored in the ASCII file secforc (*DATABASE_SECFORC).
*BOUNDARY_PRESCRIBED_MOTION_SET *CONSTRAINED_SPOTWELD *CONTACT_AUTOMATIC_SINGLE_SURFACE *CONTROL_ENERGY *CONTROL_OUTPUT *CONTROL_SHELL *CONTROL_TERMINATION *DATABASE_BINARY_D3PLOT *DATABASE_BINARY_D3THDT *DATABASE_CROSS_SECTION_PLANE *DATABASE_CROSS_SECTION_SET *DATABASE_GLSTAT *DATABASE_HISTORY_NODE *DATABASE_MATSUM *DATABASE_NODAL_FORCE_GROUP *DATABASE_NODFOR *DATABASE_NODOUT *DATABASE_SECFORC *DATABASE_SWFORC *DEFINE_CURVE *ELEMENT_SHELL *END *KEYWORD *MAT_PLASTIC_KINEMATIC *NODE *PART *SECTION_SHELL *SET_NODE_LIST *SET_SHELL_LIST *TITLE
*KEYWORD
*TITLE
Two Spotwelded Plates Pulled Apart with a Specified Velocity
$
$ LSTC Example
$
$ Last Modified: September 4, 1997
$
$ Model initially changed from old lstc example to partially reflect paper
$ by Matzenmiller, et al (ls-dyna conf 9/94) - Major differences include the
$ material and element formulation, units, and velocity loading.
$
$
$ Units: mm, kg, ms, kN, GPa, kN-mm
$
$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$
$
$$$$ Control Ouput
$
$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$
$
*CONTROL_TERMINATION
$ endtim endcyc dtmin endneg endmas
8.00
$
*CONTROL_ENERGY
$ hgen rwen slnten rylen
2 2 2
$
*CONTROL_OUTPUT
$ npopt neecho nrefup iaccop opifs ipnint ikedit
1 3
$
*CONTROL_SHELL
$ wrpang itrist irnxx istupd theory bwc miter
1
$
$
*DATABASE_BINARY_D3PLOT
$ dt lcdt
0.2
$
*DATABASE_BINARY_D3THDT
$ dt lcdt
99999
$
*DATABASE_GLSTAT
$ dt
0.010
$
*DATABASE_MATSUM
$ dt
0.010
$
*DATABASE_NODFOR
$ dt
0.010
$
*DATABASE_NODAL_FORCE_GROUP
$ nsid cid
201
$
*SET_NODE_LIST
$ sid
201
$ nid1 nid2 nid3 nid4 nid5 nid6 nid7 nid8
213 123
$
*DATABASE_NODOUT
$ dt
0.010
$
*DATABASE_HISTORY_NODE
$ id1 id2 id3 id4 id5 id6 id7 id8
123 233
$
*DATABASE_SECFORC
$ dt
0.010
$
*DATABASE_SWFORC
$ dt
0.010
$
$
$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$
$
$$$$ Constrain the Plates Together
$
$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$
$
$$$ Three spotwelds across the plate, with failure defined.
$
*CONSTRAINED_SPOTWELD
$ n1 n2 sn sf n m
212 122 7.854 4.534 2.0 2.0
213 123 7.854 4.534 2.0 2.0
214 124 7.854 4.534 2.0 2.0
$
$
$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$
$
$$$$ Boundary Motion Conditions
$
$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$
$
$$$ Prescribe the velocity of the nodes on one end of the plate.
$
*BOUNDARY_PRESCRIBED_MOTION_SET
$ nid dof vad lcid sf vid
1 1 0 1 1.0 0
$
*DEFINE_CURVE
$ lcid sidr scla sclo offa offo
1
$ abscissa ordinate
0.0000 0.0
10.0000 0.3048
20.0000 0.3048
$
*SET_NODE_LIST
$ sid
1
$ nid1 nid2 nid3 nid4 nid5 nid6 nid7 nid8
231 232 233 234 235
$
$
$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$
$
$$$$ Define Contacts
$
$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$
$
$...>....1....>....2....>....3....>....4....>....5....>....6....>....7....>....8
$
*CONTACT_AUTOMATIC_SINGLE_SURFACE
$ ssid msid sstyp mstyp sboxid mboxid spr mpr
0
$ fs fd dc vc vdc penchk bt dt
$ sfs sfm sst mst sfst sfmt fsf vsf
$
$
$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$
$
$$$$ Define Parts and Materials
$
$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$
$
*PART
$ pid sid mid eosid hgid adpopt
plate_1
1 1 1
plate_2
2 1 1
$
$
*MAT_PLASTIC_KINEMATIC
$ mid ro e pr sigy etan beta
1 2.70e-6 68.9 0.330 0.286 0.00689
$ src srp fs
$
$$$$ Element formulation 6 (S/R Hughes-Liu) is used to prevent hourglassing.
$
*SECTION_SHELL
$ sid elform shrf nip propt qr/irid icomp
1 6 3
$ t1 t2 t3 t4 nloc
2.0 2.0 2.0 2.0
$
$
$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$
$
$$$$ Define Cross Sections
$
$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$
$
$$$ Two cross sections defined - one through each plate. Two different
$ methods for defining the cross sections are used.
$
$...>....1....>....2....>....3....>....4....>....5....>....6....>....7....>....8
$
$$$ cross section through plate 1
$
*DATABASE_CROSS_SECTION_PLANE
$ psid xct yct zct xch ych zch
0 30.0 0.0 0.0 31.0 0.0 0.0
$ xhev yhev xhev lenl lenm
30.0 1.0 0.0
$
$$$ cross section through plate 2
$
*DATABASE_CROSS_SECTION_SET
$ nsid hsid bsid ssid tsid dsid
4 2
$
*SET_NODE_LIST
$ sid da1 da2 da3 da4
4
$ nid1 nid2 nid3 nid4 nid5 nid6 nid7 nid8
226 227 228 229 230
$
*SET_SHELL_LIST
$ sid da1 da2 da3 da4
2
$ eid1 eid2 eid3 eid4 eid5 eid6 eid7 eid8
221 222 223 224
$
$
$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$
$
$$$$ Define Nodes and Elements
$
$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$
$
$
*END
