When combining beams and shells, option quadratic must be deactivated (Meshing->Quadratic elements must be set to Normal). Triangles are meshed as 3-noded triangles but will be calculated internally as 6-noded triangles if problem data option is set. It is necessary to obtain good results.
If more elements are used to mesh the geometry, more accuracy in the results will be obtained. At the same time, more computer time and RAM memory is needed. Use Calculate->View process info after doing a preliminary analysis in order to obtain information of the memory requirements and the computer time needed.
It is also interesting to mesh smaller elements in the zones of the shell that will have a bigger gradient in the results.
To estimate the precision of the results related to the number of nodes in the mesh, check the test graphics given in the apendixes.
To obtain the desired sizes of the elements, use GiD options to control the mesh size like:
Meshing->Assing unstr. Sizes->Points
Meshing->Assing unstr. Sizes->Lines
Meshing->Assing unstr. Sizes->By cordal error
Before generating remember to force the meshing of the beam boundary lines by choosing:
Meshing->Mesh criteria->Mesh->Lines
And select that lines.
To generate the mesh use:
Meshing->Generate 1
In this model, a default size of 1m is chosen for the triangles. The total amount of nodes is 381 (1373 after the internal conversion to 6-noded triangles).
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