#### Connectivity definition

Definition of the elastic connectivity joint is possible:

- On the hybrid 2D-Grillage/Plate structure only.

By using of discrete (calculational) modeling, the connectivity between structural beams and plates is treated as the bracing between nodes of the discrete (calculational) model:

The same interpretation of interaction appears by modeling connectivity of the structural parts of the slab:

Properties of the connectivity are described by definition of the stiffnesses of the length less connectivity joint as:

*E _{x}* – axial stiffness of the length less connectivity in the global X direction [kN];

*E _{y}* – axial stiffness of the length less connectivity in the global Y direction [kN];

*E _{z}* – axial stiffness of the length less connectivity in the global Z direction [kN].

The axial stiffness describing "fixed" connectivity joint between plate/slab can be calculated as:

where:

*E* – Youngs modulus [Pa];

*h* – thickness of the plate/slab;

*v* – Poisson's ratio.

The flexural stiffness describing "fixed" connectivity joint between plate/slab can be calculated as:

The stiffness magnitudes of the connectivity joint defined in the range between zero and "fixed" are describing semi-rigid connectivity joint, while the defined zero value(s) – rigid less (free) connectivity joint.