• Registered: 06-09-2010
  • Posts: 21

Topic: four CCT board on two Cantilever, Something error with the input data

testhwk.out
HWKSoft http://www.hwksoft.com
#one board on the Cantilever
#beamShearCoeff is artificially enlarged.
LinearStatic nsteps 1
domain 3dShell
OutputManager tstep_all dofman_all element_all
ndofman 6 nelem 6 ncrosssect 2 nmat 2 nbc 2 nic 0 nltf 1
node 1 coords 3 0. 0.  0. bc 6 1 1 1 1 1 1
node 2 coords 3 1. 0.  0. 
node 3 coords 3 0. 1.  0. bc 6 1 1 1 1 1 1
node 4 coords 3 1. 1.  0.
node 5 coords 3 0.5 0.5 0.
node 6 coords 3 2. 2. 0.  bc 6 1 1 1 1 1 1
Beam3d 1 nodes 2 1 2 mat 1 crosssect 1 refnode 6
Beam3d 2 nodes 2 3 4 mat 1 crosssect 1 refnode 6
CCTPlate  3 nodes 3 3 4 5 mat 2 crosssect 2 bodyLoads  1 2
CCTPlate  4 nodes 3 4 2 5 mat 2 crosssect 2 bodyLoads  1 2
CCTPlate  5 nodes 3 2 1 5 mat 2 crosssect 2 bodyLoads  1 2
CCTPlate  6 nodes 3 1 3 5 mat 2 crosssect 2 bodyLoads  1 2
SimpleCS 1 thick 0.2 width 0.2 beamShearCoeff 1.e18
SimpleCS 2 thick 0.01 width 0.01 beamShearCoeff 1.e18
IsoLE 1 d 78.5 E 2.06e8 n 0.3 tAlpha 1.2e-5
IsoLE 2 d 25.6 E 0.72e8 n 0.2 tAlpha 1.0e-5
BoundaryCondition 1 loadtimefunction 1 d 0.0
DeadWeight 2 loadTimeFunction 1 Components 6 0. 0. -9.81 0.0 0.0 0.0 valtype 2
ConstantFunction 1 f(t) 1.0


oofem can't solve with the data above . what's wrong ?   Help me!

2 Reply by bp

  • bp
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  • From: Prague, Czech Rep.
  • Registered: 02-03-2007
  • Posts: 1,047

Re: four CCT board on two Cantilever, Something error with the input data

Hi,
I have found two problems:
- missing cross section properties for the beams (inertia moments)
- when combining beams and plate elements, I would recommend to use shell elements (rershell, for example) instead of plate elements - as the in plane displacements are available. As the shell element is missing rotational degree of freedom around normal, it is necessary to restrain corresponding degree of freedom in node 5. In remaining nodes there is stiffness coming from beam elements, so it is not necessary to support these. You can completely avoid this by using new tr_shell01 element (requires repository version) that has rotational degree of freedom. It has the same syntax as rershell element.

please find included corrected file.

Borek

bp's Website

3 Reply by cdn_c (edited by cdn_c 07-09-2010 11:57:02)

  • Registered: 06-09-2010
  • Posts: 21

Re: four CCT board on two Cantilever, Something error with the input data

dear bp, thanks so much!
It works!
This is my first datafile used with oofem!

I change the shell node to slave node of the beam