Wave Forces and Moments on a Gravity Pier Foundation

Abstract

Abstract:In order to understand the wave forces and moments on a gravity pier foundation which consists of an upper column and a bottom gravity base, a model experiment with a scale of 1 : 60 has been conducted in a laboratory flume. A corresponding numerical calculation by using the boundary element method has been carried out to provide a comparative analysis. It is shown by the comparisons that the numerical wave forces and moments agree well with the experimental results. It is proved that the wave forces and moments acting on the foundation are completely in their inertia dominative areas for wave loads. With the diffraction effects considered into the inertia item, appropriate inertia coefficients are assessed by the experimental results for the inertia item of the Morison equation. The formula of the inertia item can be used to estimate wave forces and moments on such gravity foundations.

Key words:gravity pier foundation| model experiment| wave forces and moments| numerical calculation| inertia coefficient

摘要：In order to understand the wave forces and moments on a gravity pier foundation which consists of an upper column and a bottom gravity base, a model experiment with a scale of 1 : 60 has been conducted in a laboratory flume. A corresponding numerical calculation by using the boundary element method has been carried out to provide a comparative analysis. It is shown by the comparisons that the numerical wave forces and moments agree well with the experimental results. It is proved that the wave forces and moments acting on the foundation are completely in their inertia dominative areas for wave loads. With the diffraction effects considered into the inertia item, appropriate inertia coefficients are assessed by the experimental results for the inertia item of the Morison equation. The formula of the inertia item can be used to estimate wave forces and moments on such gravity foundations.

关键词:gravity pier foundation| model experiment| wave forces and moments| numerical calculation| inertia coefficient

CLC Number:

U 441

WEI Chengxun *(韦承勋), ZHOU Daocheng (周道成), OU Jinping (欧进萍). Wave Forces and Moments on a Gravity Pier Foundation[J]. Journal of Shanghai Jiao Tong University (Science), 2019, 24(3): 305-312.

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