thin vs thick plates?

[vkrivoshiev]

hi

I have one question.
What is differents between thin and thick plates?
Should not calculate slabs in buildings as thick slabs in order to properly transfer the shear force of the tables in the rafters.
In Basic manual of Sap2000, they recomended shell element to be thick not thin like in you manual. Is huge difference in results shear force in beams.

http://postimg.org/image/aix7h9tip/full/
http://postimg.org/image/c2djrgecl/full/
http://postimg.org/image/yvmm34si9/
https://wiki.csiamerica.com/display/kb/ ... ick+shells

Thank you.

[b.milan]

The thick slab finite element is one of the many variations of slab finite elements.
There are two main characteristics of this finite element - sectional deplanation caused by shear force is not neglected and there is no resistance to twisting around the axis perpendicular to element's plane (basically, this finite element has no 6 degrees of freedom but 5)
This kind of finite element is intended for modeling thick plates - for instance - plates with thickness of 1m or greater.
Using thick slab finite element is not advisable for ordinary slabs in buildings because of lack of sixth degree of freedom, which could cause some other problems when combining with beams and walls, and because of the fact that for ordinary slabs, sectional deplanation caused by shear force could be neglected without any doubt.