Prediction of Buckling Load from Vibration Measurements
The linear relationship between buckling load and the square of the frequency of a structure is limited to the cases in which the fundamental vibration mode and the lowest buckling mode are the same. For cases where the two modes are different researchers in the past have suggested some empirical equations. In this study (mainly numerical) it is shown that the linear relationship is reasonably valid when the modes are approximately close to each other. However, for a simply supported rectangular plate of aspect ratio two or more, the fundamental vibration mode and the lowest buckling mode are usually different to each other. It is observed that the apparent non-linear curve in this situation consists of a few linear segments depending on the aspect ratio. The buckling load could be accurately predicted by measuring the first few frequencies, instead of just one.
Key wordsBuckling load Frequency Rectangular plates
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