求助，LS-dyna仿真冲击过程中出现问题

messle中显示如下：******** notice ******** notice ******** notice ********
* *
* This is the LS-DYNA Explicit Finite Element code. *
* Neither LSTC nor the authors assume any responsibility for *
* the validity, accuracy, or applicability of any results *
* obtained from this system. The user must verify his own *
* results. *
* *
* LSTC endeavors to make the LS-DYNA code as complete, *
* accurate and easy to use as possible. *
* Suggestions and comments are welcomed. Please report any *
* errors encountered in either the documentation or results *
* immediately to LSTC through your site focus. *
* *
* Copyright (C) 1990-2005 *
* by Livermore Software Technology Corp. (LSTC) *
* All rights reserved *
* *
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contracting memory to 330664
expanding memory to 641328
expanding memory to 1123662
expanding memory to 2548650
expanding memory to 2578650
expanding memory to 2638650
expanding memory to 2669668
expanding memory to 2731284
expanding memory to 2752144
expanding memory to 2772294
expanding memory to 3647489
expanding memory to 3726878
expanding memory to 3806267
expanding memory to 3885656
expanding memory to 5265644
expanding memory to 5345033
contracting memory to 2
LS-DYNA will perform a structural only analysis
LS-DYNA user input
ls-dyna (version 970 ) date 01/10/2005
expanding memory to 4703
expanding memory to 57452
expanding memory to 927600
expanding memory to 3515490
expanding memory to 3592136
expanding memory to 3607428
expanding memory to 5448328
expanding memory to 5450329
contracting memory to 5448538
expanding memory to 5456161
expanding memory to 6311314
expanding memory to 6873500
expanding memory to 12245817
contracting memory to 9868693
expanding memory to 10897237
expanding memory to 17477891
expanding memory to 17717307
expanding memory to 17877458
expanding memory to 19470659
contracting memory to 19470659
contracting memory to 19470659
expanding memory to 19480739
expanding memory to 19480819
contracting memory to 19480819
expanding memory to 19480833
contracting memory to 19480833
expanding memory to 19787497
The LS-DYNA time step size should not exceed 0.140E-03
to avoid contact instabilities. If the step size is
bigger then scale the penalty of the offending surface.
*** Error complex sound speed in brick element # 13569 cycle 0
*** Error complex sound speed in brick element # 13570 cycle 0
*** Error complex sound speed in brick element # 13571 cycle 0
*** Error complex sound speed in brick element # 13572 cycle 0
*** Error complex sound speed in brick element # 13574 cycle 0