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Analytical study on dynamic responses of sheet-pile groin subjected to transient lateral impulse

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 نشر من قبل Tao Wu
 تاريخ النشر 2021
  مجال البحث فيزياء
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A novel structure of sheet-pile groin consists of row piles and tied sheet has been introduced to resist the impact of tidal bore in recent years. However, the dynamic responses of the structure under tidal bore have not been carefully studied before. This paper proposed an analytical solution for the dynamic responses of the sheet-pile groin subjected to a transient lateral excitation. In order to take the flexural and longitudinal vibrations into consideration, the piles and the sheet are modeled by the Timoshenko beam (TB) theory and a one-dimensional rod, respectively. The soil around the piles is simulated by the dynamic Winkler foundation model. The excitation is considered by a lateral concentrated point load acting on the front pile. On this basis, the governing equations are constructed in time domain and solved in frequency domain, while the time-domain responses are finally obtained using the discrete Inverse Fourier Transform. The accuracy of the presented analytical solution is validated by comparing with the results obtained from the FEM simulation and a model test. The effects of properties of the sheet, the piles and the soil on the dynamic responses are investigated through a comprehensive parametric study.

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