On Validity of Equivalent Vibration Testing

The requirements for validity and reproducibility of results of the vibration testing are considered. The experimental study of durability and vibration stress loading at 10 deterministic and random modes, which was performed according to the special technique using the new sensors and test aids, demonstrated that the "equivalent" replacement of the random loading by the deterministic modeling mode is incorrect for the testing under vibration stress loading conditions but it is quite admissible for the vibration endurance testing. The structural scheme of the contactless capacity-type strain gage is presented which improves the validity of the fatigue testing results.