Abstract The work presented in this paper is focused on the development of a simplified method to study the structural response of a deeply immersed cylinder subjected to the primary shock wave generated by an underwater explosion. The proposed analytical model is based on the string-on-foundation method initially developed by Hoo Fatt and Wierzbicki, who converted the two dimensional boundary value problem of a cylindrical shell to an equivalent one-dimensional problem of a plastic string on a plastic foundation. This method has already been extended by the authors to study the shock wave response of an unstiffened cylinder immersed in shallow water. The present work focuses on deep-immersed cylinders subjected to both high hydrostatic pressure and explosion shock wave. The elastic deformation energy of the cylinder under hydrostatic pressure is first calculated and used to determine the initial conditions of the dynamic problem. Cylinder deflection and plastic deformation energy are then calculated for various immersion depths. When confronted to numerical results, the proposed model appears to underestimate the increase of deflection and absorbed energy with the immersion depth. A thorough analysis of the results post-processed from Ls-Dyna/USA finite element simulations highlights a new mechanism which is due to the action of hydrostatic pressure that continues to push inward the immersed cylinder. In order to improve the analytical model, a correction factor on the hydrostatic pressure is introduced but it is finally concluded that a new mechanism dedicated to the late action of the hydrostatic pressure still needs to be developed.

中文翻译：

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深浸圆柱体对水下爆炸产生的冲击波响应的估计

摘要 本文提出的工作重点是开发一种简化方法来研究深浸圆柱体在水下爆炸产生的初级冲击波作用下的结构响应。所提出的分析模型基于由 Hoo Fatt 和 Wierzbicki 最初开发的基础上弦法，他们将圆柱壳的二维边界值问题转换为塑性基础上塑性弦线的等效一维问题。作者已经将这种方法扩展到研究浸没在浅水中的未加筋圆柱体的冲击波响应。目前的工作重点是承受高静水压力和爆炸冲击波的深浸式圆柱体。首先计算圆柱体在静水压力下的弹性变形能，并用于确定动力学问题的初始条件。然后针对不同的浸入深度计算圆柱体挠度和塑性变形能。当面对数值结果时，所提出的模型似乎低估了随着浸入深度增加的挠度和吸收能量。对 Ls-Dyna/USA 有限元模拟后处理结果的全面分析突出了一种新机制，该机制是由于静水压力的作用继续向内推动浸入式圆柱体。为了改进分析模型，