Page 19 - Vibrations 5

−0.428 − 1.149 = 0 or = 1.256
3
3
2
1
The mode shape for the frequency is,
3

1

= (−3.372) for = √2.149
3
3
1.256

The mode shape represents a deformation pattern of the

structure for a corresponding natural frequency.

It is the ratio of amplitudes of motion at various points on

the structure when excited by its natural frequency.

= 0.746 = 0.898 = 1.466
2
3
1
1 1 1
= ( 3.437 ) = ( 0.02 ) = (−3.372)
1
3
2
−9.447 0.044 1.256

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