Structural parameters identification in the frequency domain for a white noise input

AN IDENTIFICATION METHOD IS PROPOSED FOR THE DETERMINATION OF THE COEFFICIENTS FOR A LINEAR VIBRATING SYSTEM WITH MANY DEGREES OF FREEDOM IN THE FREQUENCY DOMAIN. SOME PARAMETERS ARE DETERMINED BY IMPOSING THE MINIMUM OF THE DIFFERENCE BETWEEN THE CALCULATED AND MEASURED POWER SPECTRAL DENSITY, WHILE OTHER PARAMETERS USING THE FAST FOURIER TRANSFORM IN THE SAME MANNER. THIS PARAMETER'S IDENTIFICATION METHOD IS VERY EASY BECAUSE THE PROBLEM IS LINEAR. THE INPUT FUNCTION IS THE DIRAC'S IMPULSE. THE RESULTS OBTAINED ARE APPLIED TO AN EARTHQUAKE CASE