Question
What elements and boundary conditions are available for eigenvalue analysis, response spectrum analysis, and time history analysis?
Answer
When performing eigenvalue analysis, response spectrum analysis, and time history analysis, the following elements and boundary conditions can be used:
1. Eigenvalue analysis / Response spectrum analysis
1) Elements: Tension only / Hook / Cable, Compression only / Gap elements can be replaced with truss elements for analysis
2) Boundary Conditions: General Link and Tension only / Compression only Elastic Link can be replaced with Elastic Link of General Type for analysis.
2. Linear time history analysis
1) Elements: Same as Eigenvalue analysis / Response spectrum analysis
2) Boundary conditions: The 'Force Type' of the General Link and Tension/Compression-Only Elastic Link can be replaced by the 'General Type' of the Elastic Link for analysis.
3. Nonlinear time history analysis
1) Elements: Same as Eigenvalue analysis / Response spectrum analysis
2) Boundary conditions: Tension/Compression-only Elastic Link should be replaced with the General Type of Elastic Link for analysis.
The relationship between eigenvalue analysis and time history analysis can be summarized as follows. When the time history analysis method is selected as Mode-superposition method, eigenvalue analysis should be conducted in advance.
When the Damping Method of time history analysis is 'Modal' or 'Strain Energy Proportional', eigenvalue analysis should be conducted in advance.