Dynamic Strain Prediction Using Modal Parameters
Abstract
Vibration monitoring is conventionally performed from measurements of acceleration, velocity or displacement. However, these are not the primer parameters of interest in most structural diagnosis. Dynamic stress and strain are the appropriate parameters, which may be used in this monitoring. In some cases, strain is measured using strain gages techniques. But, when it is required to measure strain at different points, these techniques become onerous, because the strain gages must be fixed in structure and cannot be reused. In this sense, some methods have been developed to predict the dynamic strain from vibration measurements on structures. These methods basically consist in the numerical differentiation of displacement, obtained by modal analysis. Here, the dynamic strain prediction, based on hybrid modal analysis and acceleration measurements, is carried out. We used the finite difference method in the displacement to strain transformation. The displacements were obtained from measurements of acceleration and operating deflection shapes technique. The predicted strains were compared with the measured strains in the time domain. The predicted results closely agree with the measured results.
Origin : Files produced by the author(s)
Loading...