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Nonlinear Dynamic Analysis

Use the data in tutorial/13_dynamic_beam_nonlinear.

Analysis Target

The analysis target is the same cantilever beam used in the preceding Linear Dynamic Analysis.

Item Description Notes Reference
Analysis type Nonlinear dynamic analysis !SOLUTION,TYPE=DYNAMIC !DYNAMIC,TYPE=NONLINEAR
Number of nodes 525
Number of elements 240
Element type 10-node quadratic tetrahedral element !ELEMENT,TYPE=342
Material name M1 !MATERIAL,NAME=M1
Boundary conditions Restraint, concentrated load !CLOAD
Matrix solver CG/SSOR !SOLVER,METHOD=CG,PRECOND=1

Analysis Setup

Perform a nonlinear dynamic analysis by restraining displacement on the constrained surface shown in Figure 4.12.1 and applying a concentrated load to the load node. The Analysis Control Data are shown below.

Shape of the cantilever

Figure 4.12.1: Shape of the cantilever beam

Analysis Control Data beam.cnt

#  Control File for FISTR
## Analysis Control
!VERSION
 3
!WRITE,RESULT,FREQUENCY=100
!SOLUTION, TYPE=DYNAMIC
!DYNAMIC, TYPE=NONLINEAR
 1 , 1
 0.0, 0.1, 100000, 1.0000e-8
 0.5, 0.25
 1, 1, 0.0, 0.0
 1000, 3121, 100
 1, 1, 1, 1, 1, 1
## Solver Control
### Boundary Condition
!BOUNDARY, GRPID=1, AMP=AMP1
 FIX, 1, 3, 0.0
!CLOAD, GRPID=1, AMP=AMP1
 CL1,    3,    -1.0
### STEP
!STEP, CONVERG=1.0e-3
 BOUNDARY, 1
 LOAD,     1
### Material
!DENSITY
 1.0e-8
!HYPERELASTIC, TYPE=NEOHOOKE
 1000.0, 0.00005
### Solver Setting
!SOLVER,METHOD=CG,PRECOND=1,ITERLOG=NO,TIMELOG=NO
 10000, 1
 1.0e-06, 1.0, 0.0
!END

Analysis Procedure

Run fistr1.

cd FrontISTR/tutorial/13_dynamic_beam_nonlinear
fistr1 -t 4

(Run with 4 threads.)

Analysis Results

Figure 4.13.1 shows the displacement time history at the monitoring node (load node, node 3121) specified in the Analysis Control Data, plotted using Microsoft Excel. An excerpt from the monitoring-node displacement output file (dyna_disp_3121.txt) is shown below as numerical output.

Displacement time history at the monitoring node

Figure 4.13.1: Displacement time history at the monitoring node

Displacement of monitoring node dyna_disp_3121.txt

         0  0.0000E+000      3121  0.0000E+000  0.0000E+000  0.0000E+000
       100  1.0000E-006      3121  7.6885E-005 -7.3733E-005 -6.0988E-004
       200  2.0000E-006      3121  3.3089E-005 -7.5879E-006 -8.2481E-004
       300  3.0000E-006      3121  8.9272E-005 -5.6180E-005 -1.2550E-003
       400  4.0000E-006      3121  5.8434E-005 -2.9113E-005 -1.9326E-003
       500  5.0000E-006      3121  3.3598E-005 -3.7069E-005 -2.6955E-003
       600  6.0000E-006      3121  9.2438E-005 -2.9415E-005 -3.4297E-003
       700  7.0000E-006      3121  4.4742E-005 -1.9064E-005 -4.2128E-003
       800  8.0000E-006      3121  4.2702E-005 -3.7315E-005 -5.2563E-003
       900  9.0000E-006      3121  7.9468E-005  4.8283E-006 -6.1239E-003
      1000  1.0000E-005      3121  2.5902E-005 -3.1393E-005 -7.1463E-003
      1100  1.1000E-005      3121  6.9365E-005 -1.1486E-005 -8.3515E-003

Analysis Result Log 0.log

 fstr_setup: OK
#### Result step=     1
 ##### Local Summary @Node    :Max/IdMax/Min/IdMin####
 //U1    2.7619E-10      3121 -1.4312E-10   1001067
 //U2    2.6490E-10   1000353 -5.5027E-10      3121
 //U3    2.8724E-10      5121 -1.8462E-07      3121
 //V1    5.5239E-02      3121 -2.8624E-02   1001067
 //V2    5.2980E-02   1000353 -1.1005E-01      3121
 //V3    5.7448E-02      5121 -3.6925E+01      3121
 //A1    1.1048E+07      3121 -5.7248E+06   1001067
 //A2    1.0596E+07   1000353 -2.2011E+07      3121
 //A3    1.1490E+07      5121 -7.3849E+09      3121
 //E11   4.3811E-10   1000347 -3.4878E-10   1000709
 //E22   2.1254E-09   1000352 -2.1246E-09   1001427
 //E33   3.6982E-07   1001067 -3.6953E-07   1000347
 //E12   1.1329E-09   1000709 -1.1050E-09   1000352
 //E23   3.6823E-07   1000713 -3.6823E-07   1000353
 //E31   9.1796E-08   1001031 -2.7687E-07      3121
 //S11   1.4231E-02   1001067 -1.4214E-02   1000347
 //S22   1.4226E-02   1001067 -1.4210E-02   1000347
 //S33   1.5711E-02   1001067 -1.5694E-02   1000347
 //S12   2.2266E-06   1000709 -2.2148E-06   1000352
 //S23   7.3645E-04   1000713 -7.3646E-04   1000353
 //S31   1.8358E-04   1001031 -5.5379E-04      3121
 //SMS   1.7350E-03   1000347  3.4921E-43      1201
 ##### Local Summary @Element :Max/IdMax/Min/IdMin####
 //E11   6.5755E-11       176 -1.7785E-10       178
 //E22   7.2706E-10       178 -7.2236E-10       119
 //E33   1.0581E-09       239 -8.9407E-10        58
 //E12   9.6411E-10       119 -4.1741E-10        60
 //E23   2.1837E-09       119 -2.2050E-09       178
 //E31   2.5589E-10       176 -1.0737E-09       119
 //S11   5.7325E-05       178 -6.8164E-05       119
 //S22   6.0945E-05       178 -7.0539E-05       119
 //S33   6.1843E-05       178 -7.1200E-05       119
 //S12   1.9176E-06       119 -8.3014E-07        60
 //S23   4.3640E-06       119 -4.4100E-06       178
 //S31   5.1153E-07       176 -2.1545E-06       119
 //SMS   9.4730E-06       119  1.0387E-41         2
 ##### Global Summary @Node    :Max/IdMax/Min/IdMin####
 //U1    2.7619E-10      3121 -1.4312E-10   1001067
 //U2    2.6490E-10   1000353 -5.5027E-10      3121
 //U3    2.8724E-10      5121 -1.8462E-07      3121
 //V1    5.5239E-02      3121 -2.8624E-02   1001067
 //V2    5.2980E-02   1000353 -1.1005E-01      3121
 //V3    5.7448E-02      5121 -3.6925E+01      3121
 //A1    1.1048E+07      3121 -5.7248E+06   1001067
 //A2    1.0596E+07   1000353 -2.2011E+07      3121
 //A3    1.1490E+07      5121 -7.3849E+09      3121
 //E11   4.3811E-10   1000347 -3.4878E-10   1000709
 //E22   2.1254E-09   1000352 -2.1246E-09   1001427
 //E33   3.6982E-07   1001067 -3.6953E-07   1000347
 //E12   1.1329E-09   1000709 -1.1050E-09   1000352
 //E23   3.6823E-07   1000713 -3.6823E-07   1000353
 //E31   9.1796E-08   1001031 -2.7687E-07      3121
 //S11   1.4231E-02   1001067 -1.4214E-02   1000347
 //S22   1.4226E-02   1001067 -1.4210E-02   1000347
 //S33   1.5711E-02   1001067 -1.5694E-02   1000347
 //S12   2.2266E-06   1000709 -2.2148E-06   1000352
 //S23   7.3645E-04   1000713 -7.3646E-04   1000353
 //S31   1.8358E-04   1001031 -5.5379E-04      3121
 //SMS   1.7350E-03   1000347  3.4921E-43      1201
 ##### Global Summary @Element :Max/IdMax/Min/IdMin####
 //E11   6.5755E-11       176 -1.7785E-10       178
 //E22   7.2706E-10       178 -7.2236E-10       119
 //E33   1.0581E-09       239 -8.9407E-10        58
 //E12   9.6411E-10       119 -4.1741E-10        60
 //E23   2.1837E-09       119 -2.2050E-09       178
 //E31   2.5589E-10       176 -1.0737E-09       119
 //S11   5.7325E-05       178 -6.8164E-05       119
 //S22   6.0945E-05       178 -7.0539E-05       119
 //S33   6.1843E-05       178 -7.1200E-05       119
 //S12   1.9176E-06       119 -8.3014E-07        60
 //S23   4.3640E-06       119 -4.4100E-06       178
 //S31   5.1153E-07       176 -2.1545E-06       119
 //SMS   9.4730E-06       119  1.0387E-41         2

 ...

#### Result step=500000
 ##### Local Summary @Node    :Max/IdMax/Min/IdMin####
 //U1    5.2758E-02      5221 -5.2989E-02      1021
 //U2    1.0426E-03   1000750 -7.2090E-02      1021
 //U3    0.0000E+00      1001 -6.5930E-01      3121
 //V1    1.6455E+03      5217 -1.6058E+03      1019
 //V2    8.7881E+02   1000132 -2.2448E+03      1221
 //V3    1.9455E+02   1000003 -1.7874E+04      1221
 //A1    5.7327E+09      5221 -4.0019E+09      1203
 //A2    7.0089E+09      3221 -4.3280E+09   1000713
 //A3    4.9140E+09      1211 -8.4702E+09      5021
 //E11   1.0808E-02   1001104 -1.0904E-02      1003
 //E22   3.4008E-03      1203 -3.2574E-03      5203
 //E33   3.6321E-03      1103 -3.5530E-03   1001105
 //E12   3.4760E-03      1201 -2.9256E-03      1001
 //E23   9.1779E-04   1000017 -1.3462E-03      1001
 //E31   6.4324E-04   1000750 -2.5756E-03      1101
 //S11   5.0236E+01      5201 -5.2624E+01      1001
 //S22   1.8815E+01   1001098 -2.2485E+01   1000008
 //S33   1.2848E+01   1001098 -2.2485E+01   1000008
 //S12   5.3477E+00      1201 -4.5009E+00      1001
 //S23   1.4120E+00   1000017 -2.0711E+00      1001
 //S31   9.8961E-01   1000750 -3.9625E+00      1101
 //SMS   4.4276E+01      1003  6.5308E-01   1000690
 ##### Local Summary @Element :Max/IdMax/Min/IdMin####
 //E11   8.0789E-03       186 -8.0188E-03      1001
 //E22   2.1847E-03         8 -2.1148E-03       192
 //E33   2.5029E-03      1001 -2.6704E-03       186
 //E12   1.1765E-03        62 -1.0144E-03         3
 //E23   4.9965E-04         6 -5.1495E-04        66
 //E31  -1.2336E-05       125 -1.4721E-03         2
 //S11   3.3432E+01       186 -3.4438E+01         2
 //S22   7.0191E+00       183 -7.4671E+00         2
 //S33   7.6014E+00       183 -7.7370E+00         2
 //S12   1.8099E+00        62 -1.5605E+00         3
 //S23   7.6870E-01         6 -7.9223E-01        66
 //S31  -1.8979E-02       125 -2.2647E+00         2
 //SMS   3.1742E+01       186  7.0883E-01       114
 ##### Global Summary @Node    :Max/IdMax/Min/IdMin####
 //U1    5.2758E-02      5221 -5.2989E-02      1021
 //U2    1.0426E-03   1000750 -7.2090E-02      1021
 //U3    0.0000E+00      1001 -6.5930E-01      3121
 //V1    1.6455E+03      5217 -1.6058E+03      1019
 //V2    8.7881E+02   1000132 -2.2448E+03      1221
 //V3    1.9455E+02   1000003 -1.7874E+04      1221
 //A1    5.7327E+09      5221 -4.0019E+09      1203
 //A2    7.0089E+09      3221 -4.3280E+09   1000713
 //A3    4.9140E+09      1211 -8.4702E+09      5021
 //E11   1.0808E-02   1001104 -1.0904E-02      1003
 //E22   3.4008E-03      1203 -3.2574E-03      5203
 //E33   3.6321E-03      1103 -3.5530E-03   1001105
 //E12   3.4760E-03      1201 -2.9256E-03      1001
 //E23   9.1779E-04   1000017 -1.3462E-03      1001
 //E31   6.4324E-04   1000750 -2.5756E-03      1101
 //S11   5.0236E+01      5201 -5.2624E+01      1001
 //S22   1.8815E+01   1001098 -2.2485E+01   1000008
 //S33   1.2848E+01   1001098 -2.2485E+01   1000008
 //S12   5.3477E+00      1201 -4.5009E+00      1001
 //S23   1.4120E+00   1000017 -2.0711E+00      1001
 //S31   9.8961E-01   1000750 -3.9625E+00      1101
 //SMS   4.4276E+01      1003  6.5308E-01   1000690
 ##### Global Summary @Element :Max/IdMax/Min/IdMin####
 //E11   8.0789E-03       186 -8.0188E-03      1001
 //E22   2.1847E-03         8 -2.1148E-03       192
 //E33   2.5029E-03      1001 -2.6704E-03       186
 //E12   1.1765E-03        62 -1.0144E-03         3
 //E23   4.9965E-04         6 -5.1495E-04        66
 //E31  -1.2336E-05       125 -1.4721E-03         2
 //S11   3.3432E+01       186 -3.4438E+01         2
 //S22   7.0191E+00       183 -7.4671E+00         2
 //S33   7.6014E+00       183 -7.7370E+00         2
 //S12   1.8099E+00        62 -1.5605E+00         3
 //S23   7.6870E-01         6 -7.9223E-01        66
 //S31  -1.8979E-02       125 -2.2647E+00         2
 //SMS   3.1742E+01       186  7.0883E-01       114