Instability And Zero Stiffness

This page contains FAQs related to Instability and Zero Stiffness warnings in STAAD.Pro

1. Warning: More Than 12 DOF With Zero Stiffness
2. Warning when using the command: list-of-joints Elastic mat Dir YONLY SUB 10000 
3. I have analyzed a structure and find that there are instability messages in the .anl (output) file
4. If there are instability messages, does it mean my analysis results may be unsatisfactory?
5. If there are instability messages, are there any simple checks to verify whether my analysis results are satisfactory?
6. What does a zero stiffness warning message in the STAAD output file mean?
7. Spurious Degrees of Freedom
8. Zero stiffness/instability warnings at nodes of solid elements

See Also

RAM Instability In Finite Element Analysis

Structural Product TechNotes And FAQs