Dynamic response of an experimental model for offshore platforms with periodic legs

Abstract EN

A new class of offshore platforms with periodic legs is presented.

The dynamic response of this class of platforms to wave excitation is determined theoretically and experimentally.

The emphasis is placed here on studying the behavior of legs with geometric and material periodicity.

A theoretical model is developed to model the dynamics of periodic legs using the Transfer Matrix method.

The predictions of the model are validated experimentally using a scaled experimental model of an offshore platform.

The experimental model is tested inside a water basin which is provided with a water wave generator mechanism capable of generating periodic as well as random waves.

The dynamic response of the platform with periodic legs is determined for different submergence levels.

The obtained results are compared with the response when the platform is provided with plain legs.

It is found that the periodic legs are capable of attenuating considerably the vibration transmitted from the water to the platform both in the axial and lateral directions over a broad frequency band.

Comparisons between the experimental results and the theoretical predictions are found to be in close agreement.

The developed theoretical and experimental techniques provide invaluable tools for the design of this new class of offshore platforms with periodic legs.