631 Modal analysis by strain gage response

The method of conventional experimental modal analysis in our laboratory is difficult to measure the vibrational characteristic of rotary structure which was under operation. So, the final purpose is to investigate the vibrational characteristic which was under operation. For that, we analyzed the experimental mode by using strain gauge, because the acceleration pickup that had been used so far wasn\u27t able to be used which was under operation. And we investigated the vibrational characteristic by using the acceleration pickup and the calculation by computer before operating experiment. Then, we compared each other and examined the correspondence of the result used strain gauge. And we calculated strain modal shape under operating