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Dynamic Response of MDOF Structures. Equilibrium of forces condition gives the equations of motions:. Example : 2-DOF, identical mass & stiffness Free vibration. How do we solve this set of coupled equations?. By observation, the solution should be harmonic.
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Equilibrium of forces condition gives the equations of motions:
Example: 2-DOF, identical mass & stiffness Free vibration How do we solve this set of coupled equations?
By observation, the solution should be harmonic. Substituting into the equations of motion: Need to find non-trivial solution coefficient matrix has to be singular
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Scaling the Modeshapes • Arbitrary Set one modeshape coefficient equal to unity (ex: coeff. at roof level = 1.0) Mass normalized
Forced Vibration modal representation
How to find the initial conditions in the modal space? Premultiply by
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