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Typical warning message from LUSAS Solver text output file (*.OUT):


Most common causes & links to solutions 

Ideally, a joint should have zero length to avoid the possibility of obtaining a solution that is not in true moment equilibrium, but near zero length is sufficient in an analysis where this is not a factor or a concern. For a dynamic analysis the effects of a non-zero length for a joint should be considered or avoided.

Joints can be made zero length by making the points (or features) that they are defined between unmergable and coincident. To do this you will also need to ensure that automatic equivalencing is switched off (this option is off by default):

File > Model Properties... > Meshing tab > Equivalence section > (uncheck) Automatic

and a local coordinate system will need to be used to orientate the axes of the joint element as this is not now defined by the vector from one node to the other. Alternatively, it is usually sufficient to move the points, between which the joint is defined, very close together taking care to ensure that they do not merge together. This latter approach leaves a short length removing the need to use a local coordinate system to orientate the element axes. 

For further information please see:

Help > Help Topics > Contents > Modeller Reference Manual > Chapter 5 : Model Attributes > Meshing > Joint/Interface Element Meshes

Help > Help Topics > Contents > Element Reference Manual > Appendix L : Joint Element Compatibility

How to find the target Node or Element:

Solver error or warning messages are also scanned from Solver .out file and reported in Modeller Text Output window. By default the Text Output window appears at the bottom of the graphics window just above the Status Bar. This displays messages and warnings during a modelling session. Specific objects referred to in error and diagnostic messages in the text window by ID number in the form "Node P" may be identified using the identify object dialog. The Identify Object" dialog is invoked by double clicking on the message text. From this dialog the identified object may be selected, moved to the centre of the screen, scaled to fill the screen, have its properties displayed, or identified by an annotation arrow or a temporary indicator.

Nodes P and Q can also be located in the model using Advanced Selection, activated by right- clicking with the mouse in the graphics window, or via:

Edit > Advanced Selection

Joint mesh main page

General tips for using joint mesh


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