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FAQ 003443 | A single-span beam consisting of several apparently straight members receives small torsional moments in the load case of "dead load." Why?
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Question
A single-span beam consisting of several apparently straight members receives small torsional moments in the load case of "dead load." Why?Answer
There is very likely an inaccuracy in the modeling, which has to be checked as follows:
- Set the view in the member direction, then zoom in.
- Select all existing nodes that should lie on the same line: If the respective coordinates in the transverse direction do not correspond to the member axis, the corresponding field of the coordinate is empty and there is a deviation.
Keywords
Dlubal FAQ Torsion Torsional moment Implausible Undefinable Single-span beam Frequently Asked Question FAQ about Dlubal Question and Answer about Dlubal
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New
General method for stability designs according to EN 1993-1-1 and buckling in the main bearing plane
In EN 1993-1-1, the General Method was introduced as a design format for stability designs, which can be used for planar systems with any boundary conditions and variable structural height.
New
Increased Calculation Performance by Reducing the Nodal Degrees of Freedom
The number of degrees of freedom in a node is no longer a global calculation parameter in RFEM (6 degrees of freedom for each mesh node in 3D models, 7 degrees of freedom for the warping torsion analysis). Thus, each node is generally considered with a different number of degrees of freedom, which leads to a variable number of equations in the calculation.
This modification speeds up the calculation, especially for models where a significant reduction of the system could be achieved (e.g. trusses and membrane structures).
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