How is the gusset shaped for a joint with multiple secondary beams?

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The answer is exemplified on a Gusset plate for 3 diagonals connection, similar to the following figures.

This document exemplifies the design of the gusset plate for this joint. The gusset plate shape and dimensions are determined taking into account the secondary beams sections and their border conditions, the position and number of the bolt holes.

The joint connects three secondary beams to a column. All the secondary beam sections are L100x10, and the column section is IPE400. The first secondary beam is connected by four bolts; the second one is connected by three bolts and the third one is connected by two bolts.

When creating a Gusset plate for 3 diagonals all the secondary beam axes intersect on a single point, as it can be seen in the figure.

The first step in defining the gusset shape is to set the secondary beam positions. The secondary beam position is defined in the Support Beams properties window, by inserting the corresponding value for the 5.Offset Z parameter. For the first secondary beam the 5.Offset Z is 80mm and for the third secondary beam -120mm (the sign defines the offset direction).

At this stage of defining the joint, the gusset plate will look like the one in the following figure:

The following adjustments are made in the Joint properties window.

The border conditions of the secondary beams relative to the gusset plate are defined. For this, the Gusset plate parameter page must be opened. A 15mm distance is defined between the column web and each one of the secondary beams by setting this value for 2.Dist. Diag.1-profile, 3.Dist. Diag.2-profile and 4.Dist. Diag.3-profile. On the same page, the gusset plate thickness can be defined and the general form of the gusset plate. The gusset plate thickness is 10mm. The Shape option is set on Corners which means that the gusset plate corners are cut perpendicular on the axes of the secondary beams 1 and 3.

The bordering conditions of positioning the secondary beams over the gusset plate relative to the plate corners are defined on the Projection window. These dimensions are defined only for the first and the third secondary beams; the bordering conditions corresponding to the second beam will be determined automatically depending on the other beams.

The bolts corresponding to each secondary beam are defined on the Number of Bolts properties page.

In the Modeling area it can be observed that the dimension and the form of the gusset plate were modified in order to satisfy all the conditions previously set.
The next step is to define the bolt holes position relative to the end of the secondary beams or to the edge of the gusset plate.
First, the secondary beam parameters are defined. This beam is connected by four bolts. The distances between the bolts are 55mm; the distance from the beam end to the first bolt is 30mm and the distance between the last bolt and the edge of the gusset plate is 30mm. The bolts are placed in a single line over the gauge line.

The second secondary beam is connected by three bolts and the distance between them is 70mm. The distance between the first bolt and the edge of the beam is 50mm.
The distance from the last bolt to the edge of the gusset plate is determined automatically depending on the bolt position to the other secondary beams.

The two bolts connecting the third beam have a 55mm intermediate distance between them and the distance from the first bolt to the edge of the beam is 100mm. The distance between the last bolt and the edge of the gusset plate is 70mm.

It can be observed that the gusset plate dimensions and form are according to the initial specifications.