Analytical Qualification of System Identification (Modal Analysis) Codes for Use in the Dynamic Testing of Nuclear Power Plant Structures

摘要

The analytical evaluation of two particular system identification codes used at Lawrence Livermore Laboratory is presented. Both codes are eigenparameter identification codes; however, one uses a time domain approach while the other a frequency domain approach. The evaluation was accomplished by analytically generating several time history signals in which the true modal parameters were known. These time histories ranged from widely spaced modes with spacing factors of 100 percent to closely spaced modes with spacing factors of 6 percent. These signals were then polluted with various levels of simulated measurement noise and the ability of our computer codes to extract the parameters from this noisy data was evaluated. (ERA citation 05:018871)