MDOF-Rayleigh's Principle

Rayleigh’s Principle applies the principle of conservation of energy. From here, we can derive equations that help us to determine the first mode and fundamental frequency of a MDOF system.

To use this method, we need to determine the mass, stiffness and flexibility matrices for the dynamic system. Then, we simply substitute the relevant parameters into equations, calculating the displacement and subsequently the fundamental frequency of structure.

The following shows the derivation and application of Rayleigh's Principle in MDOF system. Watch the video above for full details.

Derivation 1

Derivation 2

Application in MDOF system