Interaction diagram

The parameters for interaction diagram are:

Division of strain	Calculation precision for one of the diagram "branches". The value means how many times the strain plane is readjusted from the position of section under full compression to the position of section under full tension. Default value = 180. The value influences the accuracy and the speed of calculation. See Figure 1 below.
Vertical division	Number of directions in which the diagram is calculated (number of "branches"). Default value = 72. See Figure 1 below.
Horizontal division	The value affecting the accuracy of vertical sections. Because "branches" of the diagram are not generally planar, the calculation of vertical sections is based on horizontal sections. Default value = 100. See Figure 1 below.
Method of check	The interaction diagram shows the ultimate bearing capacity. The following approaches can be applied: Nu – assuming Md is constant Mu – assuming Nd is constant NuMu – assuming eccentricity is constant Muy – assuming Mdz is constant Muz – assuming Mdy is constant Default value = Muy. See Figure 2 below.

Figure 1 - Divisions

$image\diagram_division.gif$

A = Division of strain; B = Vertical division; C = Horizontal division

Figure 2 – Method of check

$image\diagram_methods.gif$