Bottom structural response prediction for ship-powered grounding over rock-type seabed obstructions

Abstract This paper presents a simplified analytical method for predicting the resistance of ship bottom structures when a ship runs aground over rock-type seabed obstructions. During the powered grounding scenario, the structural damage caused by sharp seabed obstructions may lead to earlier penetration and serious consequences, such as compartment flooding, oil leakage and environmental pollution. Therefore, it is of great importance to rapidly and accurately analyse the response of a ship's bottom structure during powered grounding scenarios. A new simplified kinematically admissible analytical model is built to capture the dominant failure modes of the bottom transverse floor, which include plastic bending and membrane stretching, and the analytical expression of the resistance of the bottom floor is derived from a plastic mechanism analysis. The failure mechanisms of the bottom plating are also analyzed to provide insight into the main deformation mechanisms with reasonable predictive accuracy. The analytical prediction method is verified by numerical simulation using the code LS-DYNA. The simulation cases cover a wide range of indentations and semi-apex angles of the cone-shaped rocks. The results agree well, proving that the proposed analytical method can be used to predict the ship bottom structure crashworthiness during the structural design phase.

[1]  Bo Cerup Simonsen,et al.  Ship grounding on rock-I. Theory , 1997 .

[2]  G. Wang,et al.  A Simple Method for Predicting the Grounding Strength of Ships , 1997 .

[3]  Bo Cerup Simonsen,et al.  Plate tearing by a cone , 1998 .

[4]  Bo Cerup Simonsen,et al.  Ship grounding on rock—II. Validation and application , 1997 .

[5]  Yi Liu,et al.  Investigation on structural performance predictions of double-bottom tankers during shoal grounding accidents , 2013 .

[6]  Zhiqiang Hu,et al.  Plastic mechanism analysis of structural performances for stiffeners on bottom longitudinal web girders during a shoal grounding accident , 2015 .

[7]  Lin Hong,et al.  Crushing resistance of web girders in ship collision and grounding , 2008 .

[8]  Tomasz Wierzbicki,et al.  Closed-form solution for wedge cutting force through thin metal sheets , 1993 .

[9]  Bo Cerup Simonsen,et al.  Experiments and theory on deck and girder crushing , 1999 .

[10]  Shengming Zhang,et al.  Plate tearing and bottom damage in ship grounding , 2002 .

[11]  Lin Hong,et al.  Simplified Analysis and Design of Ships subjected to Collision and Grounding , 2009 .

[12]  Guoxing Lu,et al.  Cutting of a plate by a wedge , 1989 .

[13]  Bo Cerup Simonsen,et al.  Theoretical and Statistical Analysis of Ship Grounding Accidents , 2000 .

[14]  W. Q. Shen,et al.  AN EXPERIMENTAL STUDY ON THE SCALING OF PLATE CUTTING , 1998 .

[15]  N. Jones,et al.  A STUDY OF PLATE TEARING FOR SHIP COLLISION AND GROUNDING DAMAGE , 1987 .

[16]  Tomasz Wierzbicki,et al.  Crushing damage of web girders under localized static loads , 1995 .

[17]  Zhiqiang Hu,et al.  A steady-state plate tearing model for ship grounding over a cone-shaped rock , 2016 .

[18]  Jørgen Amdahl,et al.  On the resistance of tanker bottom structures during stranding , 2007 .

[19]  Jeorn K. Paik,et al.  Damage And Residual Strength Of Double-Hull Tankers In Grounding , 1995 .

[20]  Jani Romanoff,et al.  Estimating sea bottom shapes for grounding damage calculations , 2016 .

[21]  Jeom Kee Paik,et al.  Cutting of a longitudinally stiffened plate by a wedge , 1994 .

[22]  Pentti Kujala,et al.  Comparing rock shape models in grounding damage modelling , 2016 .

[23]  Hu Zhiqiang,et al.  Verification of a simplified analytical method for predictions of ship groundings over large contact surfaces by numerical simulations , 2011 .

[24]  Tomasz Wierzbicki,et al.  A theoretical study of steady-state wedge cutting through metal plates , 1996 .

[25]  Zhenguo Gao,et al.  The Resistance of Ship Web Girders in Collision and Grounding , 2014 .

[26]  Preben Terndrup Pedersen,et al.  The Mechanics of Ship Collisions , 1999 .

[27]  Eliopoulou Eleftheria,et al.  Statistical Analysis of Ship Accidents and Review of Safety Level , 2016 .

[28]  Bo Cerup Simonsen,et al.  Plasticity, Fracture and Friction in Steady-State Plate Cutting , 1997 .

[29]  H. Vaughan,et al.  THE TEARING STRENGTH OF MILD STEEL PLATE , 1980 .

[30]  Kristjan Tabri.  Influence of coupling in the prediction of ship collision damage , 2012 .

[31]  Paul James,et al.  Statistics and damage assessment of ship grounding , 2002 .