Cooperation between a plate and beams
There are two ways of cooperation to distinct:
- Either the plate is loose on the beams, which also means that they can shift laterally along each other (model A)
- Either the plate is connected to the beams, which also means that it can no longer slide laterally along each other (model B)
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The import of both calculation models in SCIA Engineer is as follows:
- Model A is obtained by not giving an eccentricity to the beams
- Model B is obtained by giving an eccentricity to the beams
The composite stiffness for both models will be as follows:
- The composite stiffness for model A is (EI)plate +(EI)beam (so just a linear summation).
- The composite stiffness for model B is (EI)whole (with plate and beam are considered as an cooperating entity)
This results in the following results in case of a loaded plate with beams in bending
- Model A: the beams and the plate will only take a bending moment and they will be dimensioned on this.
- Model B: the beams will also (in addition to a bending moment) have a resultant tensile force and the plate may also take a resulting pressure force . They will be dimensioned on this.
Note: model B can also be made by using the option 'Rib' in which a part (defined by the effective width) of the forces in the plate are included in the rib.