STRUCTURAL MODIFICATION WITH FREQUENCY-RESPONSE CONSTRAINTS FOR UNDAMPED MDOF SYSTEMS

A structural modification method which aims to change the structural design to match the desired frequency response behaviors is introduced. The calculations of frequency response sensitivities and reanalysis of frequency responses of a modified structure are efficiently carried out in a reduced modal space. Either a least square solution or an optimal solution with minimum structural weight subjected to various types of frequency response constraints can be obtained through an iteration loop which repeatedly uses the frequency response sensitivity data and reanalysis technique to achieve the design goal. A tremendous cost saving is expected when this is implemented in practical engineering design. © 1990.