Answer:
In the "Geometry" or "Supports and Releases" dialog box, you can specify in the "Supports" tab whether the support compression should be checked for a support.
In the case of an asymmetrical system, separate entries are possible for the support on the ridge, for example. This way, it is possible to determine different support widths of both rafters.
If there is a rafter birdsmouth cut, the cross-section reduction is usually known (Column D).
The supports can be related "globally" to the directions of the axes XYZ or "locally" to the directions of the member axes xyz. The corresponding selection is possible in the list.
The support orientation has effects on the design of the support compression; among other things: In the case of a global arrangement, the compressive stresses in the birdsmouth cut are considered at an angle to the grain direction according to the roof inclination; in the case of a local arrangement, under 90° to the grain direction.
