Frame21 – Bathe and Wilson Eigenvalue Problem ✔
Problem Description
A ten-bay, nine-story, two-dimensional, fixed base frame structure solved in Bathe and Wilson 1972 is analyzed for the first three eigenvalues. This model results are compared with independent results presented in Bathe and Wilson 1981 as well as independent results presented in Peterson 1981.
The material and section properties, and the mass per unit length used for all members, shown in the figure below, are consistent with those used in the two above mentioned references.
Important Note: Only bending and axial deformations are considered in the analysis. Shear deformations are ignored by setting the shear area to 0.
Library
Object Link : https://bim.aecbolt.com/objidxg3sy8lut9rpkl44dwi1w.libobj
Results Comparison
Natural Frequencies (in Hz)
Mode | AEC|BOLT BIM Cloud App | Bathe and Wilson | Comparison | Solver Value | Percent Difference AEC|BOLT BIM Cloud App - Bathe and Wilson | Percent Difference Solver Value - Bathe and Wilson |
---|---|---|---|---|---|---|
1 | 0.1222 | 0.122 | 0.122 | 0.122 | 0% | 0% |
2 | 0.3742 | 0.374 | 0.374 | 0.375 | 0% | 0.27% |
3 | 0.6523 | 0.648 | 0.648 | 0.652 | 0.66% | 0.61% |
Tested Features
- Modal analysis for eigenvalues
- Line mass assignment to frame objects