DYNAMIC ANALYSIS OF SINGLE-ANCHOR INFLATABLE DAMS

doi:10.1006/jsvi.1998.1611

Journal of Sound and Vibration

Volume 215, Issue 2, 13 August 1998, Pages 251-272

https://doi.org/10.1006/jsvi.1998.1611 Get rights and content

Abstract

Inflatable dams are flexible, cylindrical structures anchored to a foundation. The three-dimensional vibrational behaviour of single-anchor inflatable dams with fins is analyzed, both in the absence of water and in the presence of stationary or parallel flowing water. The dam is modelled as an elastic shell inflated with air and resting on a rigid foundation. The internal pressure is increased slowly until it reaches the desired value. Then the external water is applied and the equilibrium configuration is obtained. Small vibrations about this configuration are considered. The external water is assumed to be inviscid and incompressible, and potential theory is used. The infinite-frequency limit is assumed on the free surface. A boundary element technique is utilized to determine the behavior of the water, and the finite element method is applied to model the structure. Vibration frequencies and mode shapes are computed. The effects of the internal pressure, external water head, and parallel flow velocity on the vibrations of the dam are investigated, and the results are compared to those for the dam in the absence of external water.

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Regular articleDYNAMIC ANALYSIS OF SINGLE-ANCHOR INFLATABLE DAMS

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DYNAMIC ANALYSIS OF SINGLE-ANCHOR INFLATABLE DAMS