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5 Vibration of Two Degrees of Freedom System
Prob. 5.9.
5.10 For the two-storeyed frame shown in the figure, determine the natural frequencies and mode shapes. The beams at each floor are assumed to be infinitely
rigid.
Prob. 5.10.
Prob. 5.11.
5.11 Due to a rotating machine installed at the beam level, the frame of the figure
sways violently. What steps would you suggest to reduce the vibration without
changing the frequency of the machine?
5.12 A coupled system has the following equations of motion
¨
x + 1000 x − 100 θ = 0
¨
θ + 1000 x − 100 θ = 0
5 Vibration of Two Degrees of Freedom System
Prob. 5.9.
5.10 For the two-storeyed frame shown in the figure, determine the natural frequencies and mode shapes. The beams at each floor are assumed to be infinitely
rigid.
Prob. 5.10.
Prob. 5.11.
5.11 Due to a rotating machine installed at the beam level, the frame of the figure
sways violently. What steps would you suggest to reduce the vibration without
changing the frequency of the machine?
5.12 A coupled system has the following equations of motion
¨
x + 1000 x − 100 θ = 0
¨
θ + 1000 x − 100 θ = 0