I want to calculate a steel roof structure. There are rafter components and purlins consisting of steel, crossing each other with offset (by cross-section depth) at the connection point.
Is there any option for the rafter (without using an intermediate member) to transfer only vertical and shear forces and no moments? The purlin should get no torsion and both members should cross the connection point in a flexurally rigid way.
RFEM/RSTAB provide the option to enter "scissors releases", which allows you to model a crossing of two members whose diagrams of moments, shear or axial force do not affect each other.
To enter a scissors release, create a member end release with the reference system "Global" first. Then, select the "As Scissors" option.
You can enter a bending-resistant set of continuous members as shown on the left. The crossing continuous members must be provided with a scissors release on the connected member ends at the corresponding node.