Crushing resistance of web girders in ship collision and grounding

A new theoretical model for the crushing of web girders under localized in-plane loads is proposed on the basis of a comparative study of existing simplified methods and analyses of the progressive deformation process of web girders. The model captures several features of the local crushing process of the girder which have not been accounted for by any of the existing models. The behavior of web girders under in-plane loads is a relevant subject in both ship collision and grounding process as well as in the area of civil engineering. A variety of simplified methods have been proposed and developed by various authors around the latest decade. The different formulations in terms of instantaneous and mean crushing force are investigated and reproduced under some common rules for a comparative study. The predictions are compared to three series of experimental results found in literature. The applicability and correlations of these simplified methods are discussed in some detail. It is observed from the analysis of the deformation process that the existing theories cannot capture the main characteristics of the progressive crushing process. Therefore, a new simplified deformation model is proposed comprising two folding elements with the second folding element compressed partly, and a new set of simplified analytical method is developed by using plastic methods of analysis. The proposed method is verified by the three experiments, which have been used for the comparative study, and it agrees satisfactorily with the experimental results. For the purpose of practical application of the present simplified formulae, the effect of web stiffeners on the crushing resistance is studied as well as the influence of dynamic loading and the effective crushing distance.

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

[2]  Jeon Kee Paik,et al.  A benchmark study on crushing and cutting of plated structures , 1997 .

[3]  Preben Terndrup Pedersen,et al.  Numerical Study on the Effect of Buffer Bow Structure in Ship-to-ship Collisions , 2005 .

[4]  Lin Hong,et al.  Plastic design of laterally patch loaded plates for ships , 2007 .

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

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

[7]  G. Cowper,et al.  STRAIN-HARDENING AND STRAIN-RATE EFFECTS IN THE IMPACT LOADING OF CANTILEVER BEAMS , 1957 .

[8]  Ou Kitamura.  FEM approach to the simulation of collision and grounding damage , 2002 .

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

[10]  W. Abramowicz,et al.  Alexander revisited—A two folding elements model of progressive crushing of tubes , 1992 .

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

[12]  Preben Terndrup Pedersen,et al.  A Benchmark Study of Procedures for Analysis of Axial Crushing of Bulbous Bows(Summaries of Papers Published by Staff of National Maritime Research Institute at Outside Organizations) , 2007 .

[13]  W. Abramowicz.  The effective crushing distance in axially compressed thin-walled metal columns , 1983 .

[14]  Jørgen Amdahl,et al.  ENERGY ABSORPTION IN SHIP-PLATFORM IMPACTS , 1983 .

[15]  H. Pond,et al.  THE MOMENT ACTING ON A RANKINE OVOID MOVING UNDER A FREE SURFACE , 1951 .

[16]  Tomasz Wierzbicki,et al.  A moving hinge solution for axisymmetric crushing of tubes , 1986 .

[17]  Jeom Kee Paik,et al.  ON QUASI-STATIC CRUSHING OF A STIFFENED SQUARE TUBE , 1996 .

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

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

[20]  T. Wierzbicki,et al.  On the Crushing Mechanics of Thin-Walled Structures , 1983 .

[21]  Lin Hong,et al.  Plastic mechanism analysis of the resistance of ship longitudinal girders in grounding and collision , 2008 .

[22]  Jeom Kee Paik,et al.  Modelling of the internal mechanics in ship collisions , 1996 .