Example 1. Consider
a building with n = 6 floors each of
mass m = 1250 slugs (weight of 20 tons)
and the horizontal restoring force of k = 10,000
lb/ft = 5 tons/foot between floors.
Then
, and
this system reduces to the form
Compute the eigenvalues of matrix
,
and the natural frequencies
and periods P of
oscillation of the building.
Solution 1.
Enter the matrix a into Mathematica.
Compute the eigenvalues
of the matrix a, and the natural
frequencies
and periods p of
oscillation of the building.
|
λ |
|
|
||||
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
(c) John H. Mathews 2004