The study on penetration depth of a torpedo anchor in calcareous sandy bed
WANG Cheng1,2, CHEN Xiaohui1,2, YU Guoliang1,2
1.State Key Laboratory of Ocean Engineering, School of Naval Architecture, Ocean and Civil Engineering, Shanghai Jiaotong University, Shanghai 200240, China 2.Collaborative Innovation Center for Advanced Ship and Deep-Sea Exploration, Shanghai Jiaotong University, Shanghai 200240, China
Abstract：Torpedo anchor is a kind of anchorage structure with good application prospects due to its simple, fast and economical installation in ocean engineering. The penetration depth of the torpedo anchor in calcareous sandy bed is crucial to obtain its sufficient holding force for its moored structure. In this study, the torpedo anchor studied by RICHARDSON (2008) is used. Then, based on the coupled SPH (smooth particle hydrodynamics) and FEM (finite element method), the penetration depth of the torpedo anchor in calcareous sandy bed is simulated on Abaqus platform. In the numerical simulation, the influences of the impact velocity, anchor weight and friction coefficient between anchor and soil interface on the penetration depth are studied comprehensively. By comparing the numerical simulation results with the experimental results obtained by RICHARDSON (2008),we show that the coupled SPH-FEM algorithm is able to quickly and accurately simulate the penetration depth of torpedo anchor in sandy seabed. Besides, according to parametric study, the weight and impact velocity of torpedo anchor and the friction coefficient between anchor and soil would have significant influence on the penetration depths. Specifically, when the impact velocity is larger than a critical value, the penetration depth would vary approximately linearly along with the impact velocity. Finally, based on Richardson’s experimental data and 65 sets of numerical data obtained herein, an energy method is proposed to predict the penetration depth of torpedo anchor in calcareous sandy bed, which can be used for the design of dynamic anchor. Furthermore, this method is also applicable to the prediction of the penetration depth of DPA III dynamically installed anchor in calcareous sandy bed.
王呈, 陈晓辉, 喻国良. 鱼雷锚在钙质砂床中的贯入深度研究[J]. 浙江大学学报（理学版）, 2020, 47(2): 253-260.
WANG Cheng, CHEN Xiaohui, YU Guoliang. The study on penetration depth of a torpedo anchor in calcareous sandy bed. Journal of ZheJIang University(Science Edition), 2020, 47(2): 253-260.
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2020, Vol. 47 
