ANALYSIS OF POWER FLOW IN BEAMS AND FRAMEWORKS USING THE DIRECT-DYNAMIC STIFFNESS METHOD

The direct-dynamic stiffness method is applied to the vibrations of beams and frameworks. The effects of distributed loading are allowed for by using particular integrals, so that each member of the structure may be modelled as a single beam element regardless of the spatial distribution or frequency of the applied loading. The method is used to calculate the mean power flow and stored energy for a general framework which is subjected to harmonic or random excitation. An absorber/isolator element is developed for use with the analysis, and the method is applied to machine induced power flow into a beam foundation, the acoustic excitation of a beam on multiple supports, and the analysis of power flow in a grillage. © 1990.